The MAPK pathway is a signal transduction pathway that responds to extracellular stimuli and regulates various cellular processes. It involves a phosphorylation cascade from MAPKKK to MAPKK to MAPK that ultimately regulates transcription factors and gene expression. Second messengers like cAMP, IP3, and calcium amplify extracellular signals and allow cross-talk between different pathways. The MAPK pathway controls processes like cell growth, division, survival, and metabolism.
The MAP kinase pathway involves signal transduction from activated RAS protein to MAP kinase. The activated RAS starts a kinase cascade involving RAF, MEK and MAPK. MAP kinase then translocates to the nucleus and activates transcription factors like C-Fos. This leads to expression of genes involved in cell cycle progression. The JAK-STAT pathway involves phosphorylation of STAT proteins by JAK kinases upon cytokine binding. Phosphorylated STATs form dimers, enter the nucleus and regulate gene transcription. Both pathways integrate with other signaling cascades and are regulated by phosphatases and inhibitory proteins.
The JAK-STAT signaling pathway transmits signals from extracellular chemical signals to the cell nucleus, which leads to DNA transcription and cellular activity. It consists of receptors, Janus kinases (JAKs), and signal transducers and activators of transcription (STATs). When ligands bind to receptors, JAKs phosphorylate themselves and STATs, causing STAT dimers to enter the nucleus and promote transcription. Disrupted JAK-STAT signaling can cause immune deficiency and cancer. Drugs targeting JAK-STAT are used to reduce immune response and treat disorders like cancer and rheumatoid arthritis.
This presentation is about the transcription machinery that is required for the transcription in eukaryotes. The comparison between the transcription factors involved in prokaryotes and eukaryotes. The initiation of transcription and how it helps in producing a mRNA.
Genome organization refers to the sequential arrangement of genes within an organism. The genome consists of DNA packaged into chromosomes, which contain genes that code for proteins and RNA. Gene expression involves transcription of DNA into mRNA and translation of mRNA into proteins. The human genome project mapped the entire human genome sequence to further understand gene function and human health. Genome sequencing and mapping are important for disease diagnosis, drug development, and other medical applications.
The document discusses receptor tyrosine kinases (RTKs), a class of cell surface receptors that possess intrinsic tyrosine kinase activity. RTKs are activated through ligand binding and dimerization, which leads to autophosphorylation and downstream signaling. This signaling involves phosphorylation of proteins by RTKs and recruitment of adapter proteins, and results in cellular responses like cell division, differentiation, and motility. Common to all RTKs are an extracellular ligand-binding domain, a transmembrane domain, an intracellular tyrosine kinase domain, and regulatory domains.
The MAPK pathway is a signal transduction pathway that responds to extracellular stimuli and regulates various cellular processes. It involves a phosphorylation cascade from MAPKKK to MAPKK to MAPK that ultimately regulates transcription factors and gene expression. Second messengers like cAMP, IP3, and calcium amplify extracellular signals and allow cross-talk between different pathways. The MAPK pathway controls processes like cell growth, division, survival, and metabolism.
The MAP kinase pathway involves signal transduction from activated RAS protein to MAP kinase. The activated RAS starts a kinase cascade involving RAF, MEK and MAPK. MAP kinase then translocates to the nucleus and activates transcription factors like C-Fos. This leads to expression of genes involved in cell cycle progression. The JAK-STAT pathway involves phosphorylation of STAT proteins by JAK kinases upon cytokine binding. Phosphorylated STATs form dimers, enter the nucleus and regulate gene transcription. Both pathways integrate with other signaling cascades and are regulated by phosphatases and inhibitory proteins.
The JAK-STAT signaling pathway transmits signals from extracellular chemical signals to the cell nucleus, which leads to DNA transcription and cellular activity. It consists of receptors, Janus kinases (JAKs), and signal transducers and activators of transcription (STATs). When ligands bind to receptors, JAKs phosphorylate themselves and STATs, causing STAT dimers to enter the nucleus and promote transcription. Disrupted JAK-STAT signaling can cause immune deficiency and cancer. Drugs targeting JAK-STAT are used to reduce immune response and treat disorders like cancer and rheumatoid arthritis.
This presentation is about the transcription machinery that is required for the transcription in eukaryotes. The comparison between the transcription factors involved in prokaryotes and eukaryotes. The initiation of transcription and how it helps in producing a mRNA.
Genome organization refers to the sequential arrangement of genes within an organism. The genome consists of DNA packaged into chromosomes, which contain genes that code for proteins and RNA. Gene expression involves transcription of DNA into mRNA and translation of mRNA into proteins. The human genome project mapped the entire human genome sequence to further understand gene function and human health. Genome sequencing and mapping are important for disease diagnosis, drug development, and other medical applications.
The document discusses receptor tyrosine kinases (RTKs), a class of cell surface receptors that possess intrinsic tyrosine kinase activity. RTKs are activated through ligand binding and dimerization, which leads to autophosphorylation and downstream signaling. This signaling involves phosphorylation of proteins by RTKs and recruitment of adapter proteins, and results in cellular responses like cell division, differentiation, and motility. Common to all RTKs are an extracellular ligand-binding domain, a transmembrane domain, an intracellular tyrosine kinase domain, and regulatory domains.
MAPK Signaling pathway (Mitogen-activated protein kinase), how the pathway helps in regulation of mitosis, It's activation and inactivation inside the cell, roles of MAPK pathway in cancerous cell, different classes of MAP kinase in human
The document summarizes the JAK-STAT signaling pathway. It discusses how the pathway consists of receptors, Janus kinases (JAKs), and Signal Transducers and Activators of Transcription (STATs). When a ligand binds to a receptor, it activates associated JAKs which phosphorylate STATs. Phosphorylated STATs form dimers and translocate to the nucleus to regulate gene transcription. The pathway is negatively regulated by phosphatases, suppressors of cytokine signaling, and protein inhibitors of activated STATs. Experiments using STAT knockout cells and mice have helped elucidate the specific roles and regulation of the pathway.
The JAK-STAT signaling pathway transmits signals from extracellular chemicals to the nucleus, activating transcription of target genes. It consists of a cell surface receptor, associated Janus kinases (JAKs), and signal transducers and activators of transcription (STATs). When a ligand binds the receptor, JAKs phosphorylate STATs, which form dimers and translocate to the nucleus to regulate gene expression. The Ras/MAPK pathway similarly relays signals from cell surface receptors via Ras, Raf, MEK, and MAPK proteins to influence transcription. Both pathways are tightly regulated and important for processes like cell growth, differentiation, and apoptosis, with dysregulation contributing to diseases.
This document discusses intracellular and extracellular cell signaling. It defines cell signaling as communication between cells using chemical signals or ligands. Extracellular signaling occurs between cells and can be contact-dependent, paracrine, synaptic, or endocrine. Intracellular signaling involves signal transduction across the cell membrane and secondary messengers that activate intracellular signaling pathways involving protein phosphorylation or GTP-binding proteins. Key signaling pathways include G-protein coupled receptors and receptor tyrosine kinases that activate intracellular cascades to regulate processes like gene expression, cell growth, and metabolism.
Nuclear receptors regulate gene expression by binding to ligands that pass through the cell membrane via simple diffusion. These receptors are located in the cytoplasm or nucleus and bind small molecule ligands like steroids, lipids, vitamins, and thyroid hormone to function as transcriptional coactivators. Nuclear receptor ligands come in various structures including steroids like estrogen, progesterone, and androgen as well as non-steroidal lipophilic hormones such as vitamin D, retinoic acid, fatty acids, and thyroid hormone. Some receptors have unknown ligands and are called "orphan" receptors. Steroid receptors differ from peptide receptors in their half-life, speed of action, duration of effect, location, and degree of post-receptor regulation
This document discusses tyrosine kinases, which are enzymes that transfer phosphate groups and act as on-off switches in cellular functions. Tyrosine kinases are implicated in cancer development and progression. The document describes the structural classification, general characteristics, and mechanism of action of tyrosine kinases. It also discusses kinetic studies of tyrosine kinases like Bruton's tyrosine kinase and applications of tyrosine kinase inhibitors in cancer therapy and other diseases.
Kashikant Yadav presented on siRNA (short interfering RNA). siRNA is 20-25 base pairs long, similar to miRNA, and operates in the RNA interference pathway by degrading mRNA with complementary sequences, preventing translation. There are three main methods of siRNA synthesis: chemical synthesis, in vitro transcription, and digestion of long dsRNA by RNAase III or Dicer. siRNA has significance for protecting against viruses, maintaining genome stability, and offers a new tool to specifically repress genes. Potential applications include testing gene function, target validation, pathway analysis, and developing siRNA therapeutics.
Antisense technology uses short DNA sequences called oligonucleotides that are complementary to messenger RNA (mRNA) to prevent specific proteins from being synthesized. When introduced into cells, these antisense oligonucleotides bind to their target mRNA through Watson-Crick base pairing, forming RNA-DNA hybrids that are degraded by RNase H enzyme. This prevents translation and expression of the target protein. There are three generations of antisense oligonucleotides that have been developed with improved stability and targeting capabilities, including phosphorothioate, 2'-O-methyl RNA, and locked nucleic acid chemistries. Antisense technology has potential applications in treating diseases like cancer, viral infections, and genetic disorders.
Cell cycle and Regulation
* cell Division is occur in every human but these have certaint check point to preventing from the forming the defective cell or cancerious cell.
The MAP kinase pathway is a three-kinase signalling module that transmits signals from growth factor receptors to the nucleus. When Ras is activated by growth factors, it recruits and activates Raf, the first kinase in the cascade. Raf then activates MEK, which activates ERK. Active ERK translocates to the nucleus and phosphorylates transcription factors, influencing processes like cell proliferation. The three-kinase design allows for signal amplification and transmission from the membrane to the nucleus, while regulatory mechanisms maintain specificity.
The document discusses the MAP kinase pathway and JAK-STAT pathway. It describes that the MAP kinase pathway involves signal transmission from activated RAS through a protein kinase cascade to MAP kinase, which then activates transcription factors in the nucleus. It also explains that the JAK-STAT pathway involves cytokine receptors activating associated JAK kinases, which phosphorylate and activate STAT proteins that dimerize and move to the nucleus to regulate gene expression. Both pathways play important roles in signal transduction and regulating gene transcription in cells.
This document discusses gene mapping and sequencing. It begins by defining genomics and genetic markers such as RFLP, SSLP, and SNP that are used to track inheritance. Gene mapping involves determining the locus and distance between genes on chromosomes, which is important for diagnosing genetic diseases. There are two main types of gene mapping: linkage mapping which measures recombination frequency to determine if genes are linked, and physical mapping which precisely locates DNA sequences on chromosomes using techniques like fluorescence in situ hybridization. The document also discusses methods for gene sequencing, including Sanger sequencing and Maxam-Gilbert sequencing, as well as newer techniques like shotgun sequencing and Illumina sequencing.
The document discusses genetic engineering techniques. It describes the stages of gene cloning which include generating DNA fragments, inserting them into a vector, introducing the vector into host cells, and selecting clones. It also discusses various molecular tools used in genetic engineering like restriction endonucleases, vectors, host cells, and methods of gene transfer.
The document discusses receptor tyrosine kinases (RTKs), a class of cell surface receptors that possess intrinsic tyrosine kinase activity. RTKs are activated through ligand binding and dimerization, which leads to autophosphorylation and downstream signaling. This signaling involves phosphorylation of proteins by RTKs and recruitment of adaptor proteins, ultimately regulating processes like cell proliferation and differentiation. Examples of RTKs include receptors for growth factors like EGF. Mutations in RTKs can cause them to be constitutively active and contribute to cancer.
Epigenetics- Transcription regulation of gene expressionakash mahadev
This document provides information about epigenetics and histone modifications. It defines epigenetics as heritable changes in gene function that do not involve changes to the underlying DNA sequence. It discusses how histone modifications such as acetylation and methylation regulate gene expression by altering chromatin structure and recruiting other proteins. DNA methylation is also described as an important epigenetic modification that typically represses transcription. Several families of enzymes that establish these modifications, such as DNA methyltransferases and histone methyltransferases/acetyltransferases, are outlined.
This document discusses second messengers, which are intracellular molecules that amplify and spread signals from receptors on the cell surface. It describes four main classes of second messengers - cyclic nucleotides, membrane lipid derivatives, calcium ions, and gases like nitric oxide. Specifically, it examines the cAMP, cGMP, IP3/DAG, and calcium-mediated signaling pathways, outlining the ligands, effectors, and downstream effects of each messenger. It also provides details on nitric oxide and calcium signaling within cells.
Protein kinases are enzymes that phosphorylate other proteins and cause functional changes in target proteins. There are over 500 types of protein kinases in genomes that can modify about 30% of proteins. Protein kinase A, C, and G are three important protein kinases that are regulated by different mechanisms and have various functions in different cell types. Protein kinases play critical roles in many cellular processes and their dysregulation can lead to diseases like cancer.
This document provides an overview of siRNA and miRNA. It defines siRNA as short interfering RNA that is 20-25 base pairs long and similar to miRNA. miRNA is defined as a non-coding RNA molecule around 21-23 nucleotides that inhibits mRNA expression. Both siRNA and miRNA operate in the RNA interference pathway by being processed by the enzyme Dicer and interfering with gene expression by degrading complementary mRNA. The document also reviews the mechanisms and significance of RNAi, including its role in protecting against viruses, maintaining genome stability, and offering a new experimental tool to repress genes specifically.
Chromatin organization involves multiple levels of DNA packaging within the cell nucleus. The basic repeating unit is the nucleosome, which consists of 146bp of DNA wrapped around an octamer of histone proteins. Nucleosomes further compact into higher order structures like the 30nm fiber. Chromatin remodeling and epigenetic modifications like DNA methylation, histone acetylation and methylation regulate gene expression by altering chromatin structure and accessibility. These heritable changes in gene expression do not involve alterations to the underlying DNA sequence.
The document summarizes the hexose monophosphate pathway (HMP pathway), also known as the pentose phosphate pathway. It has three main functions: 1) supply NADPH, 2) convert hexoses to pentoses, and 3) enable complete oxidation of pentoses. NADPH functions as an electron donor in biosynthetic reactions, unlike NADH which generates ATP. The pathway occurs in the cytosol and is important in tissues that synthesize fatty acids and steroids, as it provides the required NADPH. Glucose utilization via this pathway varies between tissues and is higher in liver, adipose tissue, and erythrocytes. Deficiencies in enzymes in this pathway can cause
MAPK Signaling pathway (Mitogen-activated protein kinase), how the pathway helps in regulation of mitosis, It's activation and inactivation inside the cell, roles of MAPK pathway in cancerous cell, different classes of MAP kinase in human
The document summarizes the JAK-STAT signaling pathway. It discusses how the pathway consists of receptors, Janus kinases (JAKs), and Signal Transducers and Activators of Transcription (STATs). When a ligand binds to a receptor, it activates associated JAKs which phosphorylate STATs. Phosphorylated STATs form dimers and translocate to the nucleus to regulate gene transcription. The pathway is negatively regulated by phosphatases, suppressors of cytokine signaling, and protein inhibitors of activated STATs. Experiments using STAT knockout cells and mice have helped elucidate the specific roles and regulation of the pathway.
The JAK-STAT signaling pathway transmits signals from extracellular chemicals to the nucleus, activating transcription of target genes. It consists of a cell surface receptor, associated Janus kinases (JAKs), and signal transducers and activators of transcription (STATs). When a ligand binds the receptor, JAKs phosphorylate STATs, which form dimers and translocate to the nucleus to regulate gene expression. The Ras/MAPK pathway similarly relays signals from cell surface receptors via Ras, Raf, MEK, and MAPK proteins to influence transcription. Both pathways are tightly regulated and important for processes like cell growth, differentiation, and apoptosis, with dysregulation contributing to diseases.
This document discusses intracellular and extracellular cell signaling. It defines cell signaling as communication between cells using chemical signals or ligands. Extracellular signaling occurs between cells and can be contact-dependent, paracrine, synaptic, or endocrine. Intracellular signaling involves signal transduction across the cell membrane and secondary messengers that activate intracellular signaling pathways involving protein phosphorylation or GTP-binding proteins. Key signaling pathways include G-protein coupled receptors and receptor tyrosine kinases that activate intracellular cascades to regulate processes like gene expression, cell growth, and metabolism.
Nuclear receptors regulate gene expression by binding to ligands that pass through the cell membrane via simple diffusion. These receptors are located in the cytoplasm or nucleus and bind small molecule ligands like steroids, lipids, vitamins, and thyroid hormone to function as transcriptional coactivators. Nuclear receptor ligands come in various structures including steroids like estrogen, progesterone, and androgen as well as non-steroidal lipophilic hormones such as vitamin D, retinoic acid, fatty acids, and thyroid hormone. Some receptors have unknown ligands and are called "orphan" receptors. Steroid receptors differ from peptide receptors in their half-life, speed of action, duration of effect, location, and degree of post-receptor regulation
This document discusses tyrosine kinases, which are enzymes that transfer phosphate groups and act as on-off switches in cellular functions. Tyrosine kinases are implicated in cancer development and progression. The document describes the structural classification, general characteristics, and mechanism of action of tyrosine kinases. It also discusses kinetic studies of tyrosine kinases like Bruton's tyrosine kinase and applications of tyrosine kinase inhibitors in cancer therapy and other diseases.
Kashikant Yadav presented on siRNA (short interfering RNA). siRNA is 20-25 base pairs long, similar to miRNA, and operates in the RNA interference pathway by degrading mRNA with complementary sequences, preventing translation. There are three main methods of siRNA synthesis: chemical synthesis, in vitro transcription, and digestion of long dsRNA by RNAase III or Dicer. siRNA has significance for protecting against viruses, maintaining genome stability, and offers a new tool to specifically repress genes. Potential applications include testing gene function, target validation, pathway analysis, and developing siRNA therapeutics.
Antisense technology uses short DNA sequences called oligonucleotides that are complementary to messenger RNA (mRNA) to prevent specific proteins from being synthesized. When introduced into cells, these antisense oligonucleotides bind to their target mRNA through Watson-Crick base pairing, forming RNA-DNA hybrids that are degraded by RNase H enzyme. This prevents translation and expression of the target protein. There are three generations of antisense oligonucleotides that have been developed with improved stability and targeting capabilities, including phosphorothioate, 2'-O-methyl RNA, and locked nucleic acid chemistries. Antisense technology has potential applications in treating diseases like cancer, viral infections, and genetic disorders.
Cell cycle and Regulation
* cell Division is occur in every human but these have certaint check point to preventing from the forming the defective cell or cancerious cell.
The MAP kinase pathway is a three-kinase signalling module that transmits signals from growth factor receptors to the nucleus. When Ras is activated by growth factors, it recruits and activates Raf, the first kinase in the cascade. Raf then activates MEK, which activates ERK. Active ERK translocates to the nucleus and phosphorylates transcription factors, influencing processes like cell proliferation. The three-kinase design allows for signal amplification and transmission from the membrane to the nucleus, while regulatory mechanisms maintain specificity.
The document discusses the MAP kinase pathway and JAK-STAT pathway. It describes that the MAP kinase pathway involves signal transmission from activated RAS through a protein kinase cascade to MAP kinase, which then activates transcription factors in the nucleus. It also explains that the JAK-STAT pathway involves cytokine receptors activating associated JAK kinases, which phosphorylate and activate STAT proteins that dimerize and move to the nucleus to regulate gene expression. Both pathways play important roles in signal transduction and regulating gene transcription in cells.
This document discusses gene mapping and sequencing. It begins by defining genomics and genetic markers such as RFLP, SSLP, and SNP that are used to track inheritance. Gene mapping involves determining the locus and distance between genes on chromosomes, which is important for diagnosing genetic diseases. There are two main types of gene mapping: linkage mapping which measures recombination frequency to determine if genes are linked, and physical mapping which precisely locates DNA sequences on chromosomes using techniques like fluorescence in situ hybridization. The document also discusses methods for gene sequencing, including Sanger sequencing and Maxam-Gilbert sequencing, as well as newer techniques like shotgun sequencing and Illumina sequencing.
The document discusses genetic engineering techniques. It describes the stages of gene cloning which include generating DNA fragments, inserting them into a vector, introducing the vector into host cells, and selecting clones. It also discusses various molecular tools used in genetic engineering like restriction endonucleases, vectors, host cells, and methods of gene transfer.
The document discusses receptor tyrosine kinases (RTKs), a class of cell surface receptors that possess intrinsic tyrosine kinase activity. RTKs are activated through ligand binding and dimerization, which leads to autophosphorylation and downstream signaling. This signaling involves phosphorylation of proteins by RTKs and recruitment of adaptor proteins, ultimately regulating processes like cell proliferation and differentiation. Examples of RTKs include receptors for growth factors like EGF. Mutations in RTKs can cause them to be constitutively active and contribute to cancer.
Epigenetics- Transcription regulation of gene expressionakash mahadev
This document provides information about epigenetics and histone modifications. It defines epigenetics as heritable changes in gene function that do not involve changes to the underlying DNA sequence. It discusses how histone modifications such as acetylation and methylation regulate gene expression by altering chromatin structure and recruiting other proteins. DNA methylation is also described as an important epigenetic modification that typically represses transcription. Several families of enzymes that establish these modifications, such as DNA methyltransferases and histone methyltransferases/acetyltransferases, are outlined.
This document discusses second messengers, which are intracellular molecules that amplify and spread signals from receptors on the cell surface. It describes four main classes of second messengers - cyclic nucleotides, membrane lipid derivatives, calcium ions, and gases like nitric oxide. Specifically, it examines the cAMP, cGMP, IP3/DAG, and calcium-mediated signaling pathways, outlining the ligands, effectors, and downstream effects of each messenger. It also provides details on nitric oxide and calcium signaling within cells.
Protein kinases are enzymes that phosphorylate other proteins and cause functional changes in target proteins. There are over 500 types of protein kinases in genomes that can modify about 30% of proteins. Protein kinase A, C, and G are three important protein kinases that are regulated by different mechanisms and have various functions in different cell types. Protein kinases play critical roles in many cellular processes and their dysregulation can lead to diseases like cancer.
This document provides an overview of siRNA and miRNA. It defines siRNA as short interfering RNA that is 20-25 base pairs long and similar to miRNA. miRNA is defined as a non-coding RNA molecule around 21-23 nucleotides that inhibits mRNA expression. Both siRNA and miRNA operate in the RNA interference pathway by being processed by the enzyme Dicer and interfering with gene expression by degrading complementary mRNA. The document also reviews the mechanisms and significance of RNAi, including its role in protecting against viruses, maintaining genome stability, and offering a new experimental tool to repress genes specifically.
Chromatin organization involves multiple levels of DNA packaging within the cell nucleus. The basic repeating unit is the nucleosome, which consists of 146bp of DNA wrapped around an octamer of histone proteins. Nucleosomes further compact into higher order structures like the 30nm fiber. Chromatin remodeling and epigenetic modifications like DNA methylation, histone acetylation and methylation regulate gene expression by altering chromatin structure and accessibility. These heritable changes in gene expression do not involve alterations to the underlying DNA sequence.
The document summarizes the hexose monophosphate pathway (HMP pathway), also known as the pentose phosphate pathway. It has three main functions: 1) supply NADPH, 2) convert hexoses to pentoses, and 3) enable complete oxidation of pentoses. NADPH functions as an electron donor in biosynthetic reactions, unlike NADH which generates ATP. The pathway occurs in the cytosol and is important in tissues that synthesize fatty acids and steroids, as it provides the required NADPH. Glucose utilization via this pathway varies between tissues and is higher in liver, adipose tissue, and erythrocytes. Deficiencies in enzymes in this pathway can cause
Chaperones are a functionally related group of proteins that assist the covalent folding or unfolding and the assembly or disassembly of other macromolecular structures.
This document provides information about the pentose phosphate pathway (PPP), including its role in generating the reducing agent NADPH and producing ribose-5-phosphate. The PPP occurs in the cytosol and begins with the intermediate glucose-6-phosphate from glycolysis. It produces NADPH through glucose-6-phosphate dehydrogenase and provides pentoses to build nucleic acids. The PPP is especially important in red blood cells for maintaining glutathione levels and preventing oxidative damage through NADPH production. Deficiencies in glucose-6-phosphate dehydrogenase can lead to hemolytic anemia upon exposure to oxidative drugs or foods like fava beans.
The document discusses HDAC11, a class IV histone deacetylase enzyme. It provides background on epigenetics and histone acetylation. HDAC11 was discovered in 2001 as a novel HDAC with distinctive features from other classes. It has a gene on chromosome 3 and shares residues with class I and II HDACs. HDAC11 expression is highest in the brain, testis, and other tissues. It is overexpressed in several cancers and may be a potential new target for cancer treatment.
This document provides an overview of eukaryotic gene regulation. It discusses how gene expression is controlled through transcriptional regulation by transcription factors and epigenetic mechanisms involving chromatin structure and histone modifications. Specifically, it describes the classes and functions of transcription factors, how they bind to DNA and regulate transcription. It also explains how chromatin accessibility and histone modifications influence gene expression and outlines some of the enzymes involved in histone modification.
Chromatin remodeling involves modifying chromatin structure through two main classes of protein complexes: covalent histone-modifying complexes and ATP-dependent chromatin remodeling complexes. Covalent histone-modifying complexes catalyze addition or removal of elements like acetyl groups on histone tails, loosening or tightening DNA binding. ATP-dependent complexes use energy from ATP hydrolysis to move, eject, or restructure nucleosomes, exposing DNA for transcription. Chromatin remodeling plays a central role in gene expression regulation by providing dynamic access to the packaged genome.
This document provides an overview of gene expression in eukaryotes. It discusses that eukaryotic gene expression involves DNA accessibility, transcription, post-transcriptional modification, translation, and post-translational modification. It describes mechanisms that regulate gene expression, including positive and negative regulation, temporal responses to signals, chromatin remodeling, histone modifications, DNA methylation, gene copy number, and transposable elements. Finally, it discusses epigenetic mechanisms of gene regulation, including trans and cis epigenetic signals, propagation of epigenetic marks through DNA replication, and epigenetic therapies for cancer.
This document discusses gene regulation in prokaryotes and eukaryotes. It explains that gene regulation allows cells to only express genes when they are needed. In prokaryotes, gene regulation typically occurs through operons at the transcriptional level. Eukaryotic gene regulation is more complex and can occur through epigenetic, transcriptional, post-transcriptional, translational and post-translational mechanisms. Key methods of regulation include chromatin remodeling, transcription factor binding, RNA processing, mRNA degradation, and protein degradation.
Vitamin A and its derivatives (retinoids) play an important role in cell growth, differentiation and apoptosis. They are obtained through diet as retinol, retinyl esters or beta-carotene and stored in the liver. Retinol is converted through a series of oxidation reactions to produce retinoic acid, which functions as a ligand for nuclear retinoid receptors and regulates gene expression. Retinoic acid also has non-genomic functions and can regulate pathways such as PI3K independently of nuclear receptors. Rheumatoid arthritis is associated with environmental and biological factors such as smoking, elevated tumor necrosis factor-alpha levels and abnormal B cell activity. TNF-alpha promotes inflammation and is a
1) The study found that inhibiting HDAC3 with the selective inhibitor MI192 increased tubulin acetylation levels and disrupted microtubule dynamics in prostate cancer cells.
2) Knockdown of HDAC3 using siRNA also increased tubulin acetylation levels, while overexpression of HDAC3 reduced acetylation.
3) However, in vitro assays showed that the HDAC3-SMRT-DAD complex did not directly deacetylate tubulin, suggesting HDAC3 modulates tubulin acetylation indirectly.
PPARs are transcriptional factors that regulate gene expression and belong to the nuclear receptor superfamily. The three main PPAR isoforms are α, β, and γ, which vary in ligand specificity, tissue distribution, and biological functions. PPARs control processes like cellular differentiation, development and metabolism. They are activated by ligands such as fatty acids and eicosanoids and regulate energy homeostasis by initiating transcription of genes involved. Each PPAR isoform has distinct roles such as PPAR-γ promoting adipogenesis and insulin sensitization while PPAR-α stimulates fatty acid oxidation.
Histones are positively charged proteins that DNA wraps around to form nucleosomes, the basic unit of chromatin. The four core histones, H2A, H2B, H3, and H4, contain high proportions of lysine and arginine amino acids. H2A, H2B, and H1 contain more lysine while H3 and H4 contain more arginine. Histone modifications like acetylation and phosphorylation can regulate gene expression by altering chromatin structure and accessibility to transcription proteins. Acetylation reduces the positive charge of histones and weakens their interaction with DNA, allowing transcription. Phosphorylation also weakens histone-DNA interactions and influences chromatin structure and cellular processes like DNA
Nuclear receptors are a family of transcription factors that bind small molecule ligands and regulate gene expression. They contain several domains including a DNA binding domain and ligand binding domain. Upon ligand binding, nuclear receptors undergo a conformational change and recruit coactivators or corepressors to activate or repress transcription. They are classified into three classes based on their localization and dimerization properties. Class II nuclear receptors like PPARs form heterodimers with RXR, bind lipids, and regulate metabolism. PPARγ agonists like glitazones bind PPARγ, activate gene transcription, and have antidiabetic effects like sensitizing tissues to insulin.
The document discusses methylation processes and their role in human pathogenesis. It first describes how the MeCP2 protein functions in gene silencing through methyl-DNA binding and transcription repression, but that its role is more complex as a regulator rather than strict silencer of transcription. It also discusses how MeCP2 mutations cause Rett syndrome and interactions with other proteins. The role of DNA methylation in cancer is then covered, including global hypomethylation in cancer and hypermethylation of tumor suppressor genes. Finally, the potential of epigenetic therapies targeting DNA methyltransferases and histone deacetylases for cancer treatment is presented.
presented by HAFIZ M WASEEM
university of education LAHORE Pakistan
i am from mailsi vehari and studied in lahore
bsc in science college multan
msc from lahore
Eicosanoids is the class of lipids derived from arachidonic acid. Eicosanoids play an important role in the growth and development, cellular signalling, drug response, platelet action and maintenance of body homeostasis.
This document summarizes recent efforts to design small molecule epigenetic modulators that target histone acetyltransferases (HATs), histone deacetylases (HDACs), and histone methyltransferases. It describes the roles of HATs, HDACs, and histone methyltransferases in controlling gene expression through histone and DNA modifications. A handful of HAT inhibitors have been identified, including bisubstrate analogs, natural products, and synthetic small molecules. Inhibitors of HDACs and DNA methyltransferases are more established as epigenetic modulators in cancer treatment. The development of small molecule inhibitors targeting the various writers, erasers, and readers of epigenetic marks offers promise
Histamines are chemical messengers that communicate between cells. Antihistamines competitively inhibit histamines from binding to H1 and H2 receptors. First generation antihistamines are sedating but treat allergy symptoms, while second generation antihistamines are non-sedating. Cimetidine was the first H2 antagonist developed for treating gastric acid secretion by competitively blocking histamine at H2 receptors on parietal cells. It helped establish structural requirements for selective H2 receptor antagonism through its imidazole and substituted guanidine groups.
The document discusses gene expression and regulation in eukaryotes. It covers several key points in 3 sentences:
Eukaryotic genes require complex regulatory systems involving chromatin remodeling and transcription factors to initiate expression, unlike bacterial genes which can be transcribed without regulatory proteins. Development in multicellular organisms is controlled by signaling between cells using hormones and diffusible receptors which act as transcriptional regulators. Gene expression patterns in fruit flies establish polarity, segment the body, and determine segment identities through maternal, segmentation, and homeotic genes, providing insights into human developmental gene regulation.
Respiratory stimulants: types, complete discussion on indications, contraindications, assessment, patient notes and examples of stimulants both central and respiratory
Expectorants and Antitussives: types, complete discussion on indications, contraindications, assessment, patient notes and examples of expectorants and antitussives
The document discusses the actions of adrenocorticotropic hormone (ACTH) and corticosteroids. ACTH stimulates the adrenal cortex to produce corticosteroids like cortisol and aldosterone. Corticosteroids have mineralocorticoid effects like sodium retention and glucocorticoid effects like increasing blood glucose. They suppress inflammation and immune responses. Common glucocorticoids used include hydrocortisone, prednisone, and dexamethasone. Aldosterone is the main mineralocorticoid. Corticosteroids have many beneficial effects but also side effects like high blood pressure, bone loss, and weight gain if overused.
Complete pharmacology of Non steroidal Anti inflammatory Drugs, classification, Mechanism of action, Pharmacological actions, Indications, Contraindications, Adverse effects
Pharmacology laboratory experiment, both invivo and invitro includes interpolation, matching , bracketing, three point, four point bioassays with a note on hypoglycemic activity, acute skin irritation, acute eye irritaiton, pyrogen test, gastrointestinal motility test, physiological salt solutions
This document discusses antiplatelet drugs, including their indications, mechanisms of action, administration, adverse effects, and limitations. Antiplatelet drugs are classified as oral or parenteral agents and can include aspirin, clopidogrel, ticagrelor, prasugrel, cilostazol, dipyridamole, tirofiban, and eptifibatide. They work by various mechanisms including inhibiting platelet aggregation and receptor antagonism. Common indications are acute coronary syndrome, stenting and other cardiovascular procedures. Adverse effects include bleeding risks, while limitations include variable patient responses, administration methods, and side effect profiles.
This document defines and describes the main types of shock: hypovolemic, septic, cardiogenic, neurogenic, and anaphylactic shock. For each type of shock, the summary lists common causes, symptoms, diagnostic tests, and typical treatments.
Integrating Ayurveda into Parkinson’s Management: A Holistic ApproachAyurveda ForAll
Explore the benefits of combining Ayurveda with conventional Parkinson's treatments. Learn how a holistic approach can manage symptoms, enhance well-being, and balance body energies. Discover the steps to safely integrate Ayurvedic practices into your Parkinson’s care plan, including expert guidance on diet, herbal remedies, and lifestyle modifications.
share - Lions, tigers, AI and health misinformation, oh my!.pptxTina Purnat
• Pitfalls and pivots needed to use AI effectively in public health
• Evidence-based strategies to address health misinformation effectively
• Building trust with communities online and offline
• Equipping health professionals to address questions, concerns and health misinformation
• Assessing risk and mitigating harm from adverse health narratives in communities, health workforce and health system
Basavarajeeyam is a Sreshta Sangraha grantha (Compiled book ), written by Neelkanta kotturu Basavaraja Virachita. It contains 25 Prakaranas, First 24 Chapters related to Rogas& 25th to Rasadravyas.
Local Advanced Lung Cancer: Artificial Intelligence, Synergetics, Complex Sys...Oleg Kshivets
Overall life span (LS) was 1671.7±1721.6 days and cumulative 5YS reached 62.4%, 10 years – 50.4%, 20 years – 44.6%. 94 LCP lived more than 5 years without cancer (LS=2958.6±1723.6 days), 22 – more than 10 years (LS=5571±1841.8 days). 67 LCP died because of LC (LS=471.9±344 days). AT significantly improved 5YS (68% vs. 53.7%) (P=0.028 by log-rank test). Cox modeling displayed that 5YS of LCP significantly depended on: N0-N12, T3-4, blood cell circuit, cell ratio factors (ratio between cancer cells-CC and blood cells subpopulations), LC cell dynamics, recalcification time, heparin tolerance, prothrombin index, protein, AT, procedure type (P=0.000-0.031). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and N0-12 (rank=1), thrombocytes/CC (rank=2), segmented neutrophils/CC (3), eosinophils/CC (4), erythrocytes/CC (5), healthy cells/CC (6), lymphocytes/CC (7), stick neutrophils/CC (8), leucocytes/CC (9), monocytes/CC (10). Correct prediction of 5YS was 100% by neural networks computing (error=0.000; area under ROC curve=1.0).
Muktapishti is a traditional Ayurvedic preparation made from Shoditha Mukta (Purified Pearl), is believed to help regulate thyroid function and reduce symptoms of hyperthyroidism due to its cooling and balancing properties. Clinical evidence on its efficacy remains limited, necessitating further research to validate its therapeutic benefits.
8 Surprising Reasons To Meditate 40 Minutes A Day That Can Change Your Life.pptxHolistified Wellness
We’re talking about Vedic Meditation, a form of meditation that has been around for at least 5,000 years. Back then, the people who lived in the Indus Valley, now known as India and Pakistan, practised meditation as a fundamental part of daily life. This knowledge that has given us yoga and Ayurveda, was known as Veda, hence the name Vedic. And though there are some written records, the practice has been passed down verbally from generation to generation.
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Rasamanikya is a excellent preparation in the field of Rasashastra, it is used in various Kushtha Roga, Shwasa, Vicharchika, Bhagandara, Vatarakta, and Phiranga Roga. In this article Preparation& Comparative analytical profile for both Formulationon i.e Rasamanikya prepared by Kushmanda swarasa & Churnodhaka Shodita Haratala. The study aims to provide insights into the comparative efficacy and analytical aspects of these formulations for enhanced therapeutic outcomes.
These lecture slides, by Dr Sidra Arshad, offer a quick overview of the physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar lead (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
6. Describe the flow of current around the heart during the cardiac cycle
7. Discuss the placement and polarity of the leads of electrocardiograph
8. Describe the normal electrocardiograms recorded from the limb leads and explain the physiological basis of the different records that are obtained
9. Define mean electrical vector (axis) of the heart and give the normal range
10. Define the mean QRS vector
11. Describe the axes of leads (hexagonal reference system)
12. Comprehend the vectorial analysis of the normal ECG
13. Determine the mean electrical axis of the ventricular QRS and appreciate the mean axis deviation
14. Explain the concepts of current of injury, J point, and their significance
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. Chapter 3, Cardiology Explained, https://www.ncbi.nlm.nih.gov/books/NBK2214/
7. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
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Osteoporosis is an increasing cause of morbidity among the elderly.
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2. • Histone deacetylases (HDAC) are a class
of enzymes that remove acetyl groups (O=C-CH3)
from an ε-N-acetyl lysine amino acid on a histone,
allowing the histone to wrap the DNA more tightly.
• This is important because DNA is wrapped around
histone, and DNA expression is regulated by
acetylation and de-acetylation.
3. • Its action is opposite to that of histone
acetyltransferase.
• HDAC proteins are now also called lysine
deacetylases (KDAC), to describe their function
rather than their target, which also includes non-
histone proteins
4.
5. HDAC super family
• Together with the acetyl polyamine
amidohydrolases and the acetoin utilization proteins,
the histone deacetylases form an ancient protein
superfamily known as the histone deacetylases
superfamily.
6. • Classes of HDACs in higher eukaryotes.
• HDACs, are classified in four classes depending on
sequence homology to the yeast original enzymes and
domain organization:
11. • HDAC (except class III) contain zinc and are known as
Zn2+-Dependent Histone Deacetylases.
• They feature a classical arginase fold and are structurally
and mechanistically distinct from sirtuins (class III),
which fold into a Rossmann architecture and
are NAD+ dependent.
12. Subtypes
• HDAC proteins are grouped into four classes based on function and DNA
sequence similarity.
• Class I, II and IV are considered "classical" HDACs whose activities are
inhibited by trichostatin A (TSA) and have a zinc dependent active site,
whereas Class III enzymes are a family of NAD+-dependent proteins known
as sirtuins and are not affected by TSA.
• Homologues to these three groups are found in yeast having the names:
reduced potassium dependency 3 (Rpd3), which corresponds to Class I; histone
deacetylases 1 (hda1), corresponding to Class II; and silent information
regulator 2 (Sir2), corresponding to Class III.
13. • Class IV contains just one isoform (HDAC11), which is not
highly homologous with either Rpd3 or hda1 yeast
enzymes, and therefore HDAC11 is assigned to its own class.
• The Class III enzymes are considered a separate type of
enzyme and have a different mechanism of action; these
enzymes are NAD+-dependent, whereas HDACs in other
classes require Zn2+ as a cofactor.
14.
15.
16. Evolution
• HDACs are conserved across evolution, showing orthologs in
all eukaryotes and even in Archaea.
• All upper eukaryotes, including vertebrates, plants and
arthropods, possess at least one HDAC per class, while most
vertebrates carry the 11 canonical HDACs, with the exception
of bone fish, which lack HDAC2 but appears to have an extra
copy of HDAC11, dubbed HDAC12.
17.
18. • Plants carry additional HDACs compared to animals,
putatively to carry out the more complex transcriptional
regulation required by these sessile organisms.
• HDACs appear to be deriving from an ancestral acetyl-binding
domain, as HDAC homologs have been found in bacteria in
the form of Acetoin utilization proteins (AcuC) proteins
19. Sub cellular distribution
• Within the Class I HDACs, HDAC 1, 2, and 3 are found
primarily in the nucleus, whereas HDAC8 is found in both the
nucleus and the cytoplasm, and is also membrane-associated.
• Class II HDACs (HDAC4, 5, 6, 7 9, and 10) are able to shuttle
in and out of the nucleus, depending on different signals.
20. • HDAC6 is a cytoplasmic, microtubule-associated
enzyme.
• HDAC6 deacetylates tubulin, Hsp90, and cortactin,
and forms complexes with other partner proteins, and
is, therefore, involved in a variety of biological
processes.
21. Function
Histone modification:
• Histone tails are normally positively charged due to amine groups
present on their lysine and arginine amino acids.
• These positive charges help the histone tails to interact with and
bind to the negatively charged phosphate groups on the DNA
backbone.
• Acetylation, which occurs normally in a cell, neutralizes the positive
charges on the histone by changing amines into amides and
decreases the ability of the histone to bind to DNA.
22. • This decreased binding allows chromatin expansion,
permitting genetic transcription to take place.
• Histone deacetylases remove those acetyl groups, increasing
the positive charge of histone tails and encouraging high-
affinity binding between the histones and DNA backbone.
• The increased DNA binding condenses DNA structure,
preventing transcription.
23. • Histone deacetylases is involved in a series of pathways
within the living system.
• According to the Kyoto Encyclopaedia of Genes and
Genomes (KEGG), these are:
1. Environmental information processing; signal
transduction; notch signalling pathway
2. Cellular processes; cell growth and death; cell cycle
3. Human diseases; cancers; chronic myeloid leukaemia
24. • Histone acetylation plays an important role in the regulation of
gene expression.
• Hyper acetylated chromatin is transcriptionally active, and
hypoacetylated chromatin is silent.
• A study on mice found that a specific subset of mouse genes
(7%) was deregulated in the absence of HDAC1.
25. • Their study also found a regulatory crosstalk
between HDAC1 and HDAC2 and suggest a novel function
for HDAC1 as a transcriptional coactivator.
• HDAC1 expression was found to be increased in the prefrontal
cortex of schizophrenia subjects negatively correlating with
the expression of GAD67 mRNA.
26. Non-histone effects
• It is a mistake to regard HDACs solely in the context of regulating
gene transcription by modifying histones and chromatin structure,
although that appears to be the predominant function. The function,
activity, and stability of proteins can be controlled by post-
translational modifications.
• Protein phosphorylation is perhaps the most widely studied and
understood modification in which certain amino acid residues are
phosphorylated by the action of protein kinases or dephosphorylated
by the action of phosphatases.
27. • The acetylation of lysine residues is emerging as an
analogous mechanism, in which non-histone proteins are
acted on by acetylases and deacetylases.
• It is in this context that HDACs are being found to
interact with a variety of non-histone proteins—some of
these are transcription factors and co-regulators, some are
not.
28. Note the following four examples:
1. HDAC6 is associated with aggresomes.
– Misfolded protein aggregates are tagged by ubiquitination and removed
from the cytoplasm by dynein motors via the microtubule network to an
organelle termed the aggresome.
– HDAC 6 binds polyubiquitinated misfolded proteins and links to dynein
motors, thereby allowing the misfolded protein cargo to be physically
transported to chaperones and proteasomes for subsequent destruction.
– HDAC6 is important regulator of HSP90 function and its inhibitor
proposed to treat metabolic disorders.
29. 2. PTEN is an important phosphatase involved in cell signaling
via phosphoinositols and the AKT/PI3 kinase pathway.
• PTEN is subject to complex regulatory control via
phosphorylation, ubiquitination, oxidation and acetylation.
• Acetylation of PTEN by the histone acetyltransferase
p300/CBP-associated factor (PCAF) can repress its activity;
on the converse, deacetylation of PTEN by SIRT1 deacetylase
and, by HDAC1, can stimulate its activity.
30. 3. APE1/Ref-1 (APEX1) is a multifunctional protein possessing both
DNA repair activity (on abasic and single-strand break sites) and
transcriptional regulatory activity associated with oxidative stress.
• APE1/Ref-1 is acetylated by PCAF; on the converse, it is stably
associated with and deacetylated by Class I HDACs.
• The acetylation state of APE1/Ref-1 does not appear to affect
its DNA repair activity, but it does regulate its transcriptional
activity such as its ability to bind to the PTH promoter and initiate
transcription of the parathyroid hormone gene.
31. 4. NF-κB is a key transcription factor and effector molecule
involved in responses to cell stress, consisting of a p50/p65
heterodimer.
• The p65 subunit is controlled by acetylation via PCAF and by
deacetylation via HDAC3 and HDAC6.
32. Neurodegenerative diseases
• Inherited mutations in the gene encoding FUS,
an RNA/DNA binding protein, are causally linked
to amyotrophic lateral sclerosis (ALS).
• FUS has a pivotal role in the DNA damage response involving
its direct interaction with histone deacetylase 1 (HDAC1).
• ALS mutant FUS proteins are defective in the DNA damage
response and in recombinational DNA repair, and also show
reduced interaction with HDAC1.
33. • Ataxia-telangiectasia is due to mutation in the Atm gene. Wild-
type Atm encodes a protein kinase employed in chromatin
remodeling and in epigenetic alterations that are required
for repairing DNA double-strand breaks.
• Atm mutation causes neurons to accumulate nuclear histone
deacetylase 4 (HDAC4) resulting in increased histone deacetylation
and altered neuronal gene expression that likely contributes to
the neurodegeneration characteristic of ataxia-telangiectasia.
34. HDAC inhibitors
• Histone deacetylase inhibitors (HDIs) have a long history of use in
psychiatry and neurology as mood stabilizers and anti-epileptics, for
example, valproic acid.
• In more recent times, HDIs are being studied as a mitigator or treatment
for neurodegenerative diseases.
• Also in recent years, there has been an effort to develop HDIs for cancer
therapy.
• Vorinostat (SAHA) was FDA approved in 2006 for the treatment of
cutaneous manifestations in patients with cutaneous T cell
lymphoma (CTCL) that have failed previous treatments.
35. • A second HDI, Istodax (romidepsin), was approved in 2009 for
patients with CTCL. The exact mechanisms by which the
compounds may work are unclear, but epigenetic pathways are
proposed.
• In addition, a clinical trial is studying valproic acid effects on the
latent pools of HIV in infected persons.
• HDIs are currently being investigated as chemosensitizers for
cytotoxic chemotherapy or radiation therapy, or in association with
DNA methylation inhibitors based on in vitro synergy.
• Isoform selective HDIs which can aid in elucidating role of
individual HDAC isoforms have been developed.
36. • HDAC inhibitors have effects on non-histone proteins that
are related to acetylation.
• HDIs can alter the degree of acetylation of these molecules
and, therefore, increase or repress their activity.
• For the four examples given above (see Function) on
HDACs acting on non-histone proteins, in each of those
instances the HDAC inhibitor Trichostatin A (TSA) blocks
the effect.
37. • HDIs have been shown to alter the activity of many
transcription factors, including ACTR, cMyb,
E2F1, EKLF, FEN 1, GATA, HNF-4, HSP90, Ku70,
NFκB, PCNA, p53, RB, Runx, SF1 Sp3, STAT, TFIIE, TCF,
YY1.
38. • The ketone body β-hydroxybutyrate has been shown in mice to
increase gene expression of FOXO3a by histone deacetylases inhibition.
• Histone deacetylases inhibitors may modulate the latency of some viruses,
resulting in reactivation.
• This has been shown to occur, for instance, with a latent human
herpesvirus-6 infection.
• Histone deacetylases inhibitors have shown activity against
certain Plasmodium species and stages which may indicate they have
potential in malaria treatment. It has been shown that HDIs accumulate
acetylated histone H3K9/H3K14, a downstream target of class I HDACs.