1) The document discusses the mechanisms of transcriptional control in eukaryotes. It describes the core promoter elements, general transcription factors, and how they assemble to form the pre-initiation complex at RNA polymerase II promoters.
2) It also discusses the various classes of transcription factors that regulate gene expression, including their DNA-binding domains like zinc fingers, helix-turn-helices, and leucine zippers.
3) Transcription factor activity is regulated by ligands, co-factors, cooperative binding, and their assembly into enhanceosomes at gene enhancer elements.
This document discusses the regulation of gene expression through transcriptional control mechanisms. It begins by explaining that gene expression is regulated by extracellular signals through modification of transcription factors, and that this transcriptional regulation plays important roles in nervous system functioning. It then describes the various steps in the process of gene expression, with a focus on transcriptional regulation. Specifically, it explains that transcription initiation is a key control point, and involves positioning RNA polymerase at start sites and controlling initiation rates. Core promoters set the start sites and direction of transcription for RNA polymerases. Transcription factors are also described as key regulators that recruit the basal transcription complex and achieve significant transcription levels.
Basics of Undergraduate/university fellows
Transcription is more complicated in eukaryotes than in prokaryotes because
eukaryotes possess three different classes of RNA polymerases and because of the
way in which transcripts are processed to their functional forms.
More proteins and transcription factors are involved in eukaryotic transcription.
Gene expression in eukaryotes is controlled at multiple levels, including chromatin structure, transcription, RNA processing, and translation. Chromatin structure determines if genes are transcriptionally active or inactive. Transcription is regulated by the interaction of promoters, transcription factors, and enhancers. RNA processing controls splicing and transport of mRNA. Finally, translation and post-translational modifications further regulate gene expression. Overall, eukaryotic gene expression is tightly controlled through complex mechanisms at the chromatin, transcription, RNA, translation, and protein levels.
The document summarizes RNA synthesis and post-transcriptional modifications. It discusses how RNA is synthesized from a DNA template in the 5' to 3' direction by RNA polymerases. It also describes the differences between prokaryotic and eukaryotic transcription, such as eukaryotes having multiple RNA polymerases and transcription occurring separately from translation. Specific transcription factors that regulate gene expression by binding to regulatory DNA sequences are also mentioned.
RNA polymerases are enzymes that transcribe DNA into RNA. In prokaryotes, a single RNA polymerase synthesizes RNA, while eukaryotes contain three RNA polymerases that synthesize different RNA molecules. RNA polymerases are large complex protein machines made of multiple subunits that work together to unwind DNA, add nucleotides, and proofread the newly synthesized RNA. The transcription process involves initiation, elongation, and termination stages that are regulated by various transcription factors.
Promoters and enhancers contain binding sites for transcription factors that are important for initiating transcription. Promoters are located near the start site of transcription and contain binding sites dispersed over 200 bp. Enhancers can be located farther away, containing a more closely packed array of binding sites, and enhance transcription by interacting with proteins bound at the promoter. Eukaryotic transcription involves RNA polymerases and many transcription factors that recognize specific sequences in promoters and enhancers to regulate when and where genes are expressed.
Transcriptional and Post-transcriptional Regulation of Gene Expression.pptxPrabhatSingh628463
Mr. Prabhat Kumar Singh presented on transcriptional and post-transcriptional regulation of gene expression. There are two main steps in gene expression - transcription and translation. Transcription involves creating mRNA with RNA polymerase enzymes. Translation involves using mRNA to direct protein synthesis. Regulation can occur at multiple levels including replication, transcription, post-transcription, and translation. Transcriptional regulation differs between prokaryotes and eukaryotes due to eukaryotes having nuclei. Prokaryotes use operon systems like the lac and trp operons to regulate transcription. Eukaryotes use promoter elements like TATA boxes. Post-transcriptional regulation in eukaryotes includes RNA splicing and modifications. Pro
This document discusses the regulation of gene expression through transcriptional control mechanisms. It begins by explaining that gene expression is regulated by extracellular signals through modification of transcription factors, and that this transcriptional regulation plays important roles in nervous system functioning. It then describes the various steps in the process of gene expression, with a focus on transcriptional regulation. Specifically, it explains that transcription initiation is a key control point, and involves positioning RNA polymerase at start sites and controlling initiation rates. Core promoters set the start sites and direction of transcription for RNA polymerases. Transcription factors are also described as key regulators that recruit the basal transcription complex and achieve significant transcription levels.
Basics of Undergraduate/university fellows
Transcription is more complicated in eukaryotes than in prokaryotes because
eukaryotes possess three different classes of RNA polymerases and because of the
way in which transcripts are processed to their functional forms.
More proteins and transcription factors are involved in eukaryotic transcription.
Gene expression in eukaryotes is controlled at multiple levels, including chromatin structure, transcription, RNA processing, and translation. Chromatin structure determines if genes are transcriptionally active or inactive. Transcription is regulated by the interaction of promoters, transcription factors, and enhancers. RNA processing controls splicing and transport of mRNA. Finally, translation and post-translational modifications further regulate gene expression. Overall, eukaryotic gene expression is tightly controlled through complex mechanisms at the chromatin, transcription, RNA, translation, and protein levels.
The document summarizes RNA synthesis and post-transcriptional modifications. It discusses how RNA is synthesized from a DNA template in the 5' to 3' direction by RNA polymerases. It also describes the differences between prokaryotic and eukaryotic transcription, such as eukaryotes having multiple RNA polymerases and transcription occurring separately from translation. Specific transcription factors that regulate gene expression by binding to regulatory DNA sequences are also mentioned.
RNA polymerases are enzymes that transcribe DNA into RNA. In prokaryotes, a single RNA polymerase synthesizes RNA, while eukaryotes contain three RNA polymerases that synthesize different RNA molecules. RNA polymerases are large complex protein machines made of multiple subunits that work together to unwind DNA, add nucleotides, and proofread the newly synthesized RNA. The transcription process involves initiation, elongation, and termination stages that are regulated by various transcription factors.
Promoters and enhancers contain binding sites for transcription factors that are important for initiating transcription. Promoters are located near the start site of transcription and contain binding sites dispersed over 200 bp. Enhancers can be located farther away, containing a more closely packed array of binding sites, and enhance transcription by interacting with proteins bound at the promoter. Eukaryotic transcription involves RNA polymerases and many transcription factors that recognize specific sequences in promoters and enhancers to regulate when and where genes are expressed.
Transcriptional and Post-transcriptional Regulation of Gene Expression.pptxPrabhatSingh628463
Mr. Prabhat Kumar Singh presented on transcriptional and post-transcriptional regulation of gene expression. There are two main steps in gene expression - transcription and translation. Transcription involves creating mRNA with RNA polymerase enzymes. Translation involves using mRNA to direct protein synthesis. Regulation can occur at multiple levels including replication, transcription, post-transcription, and translation. Transcriptional regulation differs between prokaryotes and eukaryotes due to eukaryotes having nuclei. Prokaryotes use operon systems like the lac and trp operons to regulate transcription. Eukaryotes use promoter elements like TATA boxes. Post-transcriptional regulation in eukaryotes includes RNA splicing and modifications. Pro
The document summarizes transcription and RNA processing in cells. There is a two step process of transcription and translation required for protein synthesis. Transcription involves synthesizing RNA from a DNA template in the nucleus. Translation occurs in the cytoplasm and converts mRNA into a polypeptide chain. Eukaryotic mRNA undergoes processing including 5' capping, polyadenylation, and splicing of introns from exons before it can be translated. Prokaryotic transcription initiation and termination differ from eukaryotes and involve RNA polymerase binding promoters and terminator sequences.
Prokaryotic transcription involves RNA polymerase binding to promoter sequences on DNA and synthesizing RNA without the need for primers. It proceeds through initiation, elongation, and termination stages. Eukaryotic transcription is more complex, utilizing three RNA polymerases and involving transcription factors, mediator complexes, 5' capping, splicing, and 3' polyadenylation to process mRNA. Alternative splicing allows single genes to code for multiple proteins through different combinations of exons.
This document summarizes transcriptional gene regulation in eukaryotes. It discusses the basic mechanisms of transcription including initiation, elongation, and termination. It describes the role of general transcription factors, promoter elements like TATA boxes, and RNA polymerase in basal transcription. It also explains how distal enhancer elements and transcription factors regulate gene expression by interacting with the promoter and basal transcription machinery. Chromatin structure is also noted to influence transcription. The modular and combinatorial nature of transcriptional control is emphasized.
Transcription factors and their role in plant disease resistanceSachin Bhor
Transcription factors play an important role in regulating plant gene expression and disease resistance. GhWRKY15 is a transcription factor that has been shown to enhance resistance to viruses and fungi in tobacco plants. Overexpression of GhWRKY15 in tobacco increased the expression of pathogenesis-related genes and activated antioxidant enzymes, reducing reactive oxygen species accumulation. GhWRKY15 was also found to affect plant growth and development, with transgenic tobacco plants exhibiting altered stem morphology and accelerated flowering. The presentation discussed the structure, mechanisms and important families of transcription factors in plants, using GhWRKY15 as a case study to illustrate how transcription factors regulate stress responses.
This document discusses transcriptional gene regulation in eukaryotes. It describes how gene expression is controlled through the regulation of transcription, which involves basal transcription factors, proximal promoter elements, distal enhancer and silencer elements, and the binding of transcription factors to cis-regulatory modules. Chromatin structure also influences transcription through modifications that can activate or repress gene expression. Multiple levels of gene regulation allow for fine-tuned and combinatorial control of transcription in eukaryotic cells.
This document discusses various classes of transcriptional regulatory elements. It begins by introducing transcriptional regulation and the basic transcriptional machinery. It then discusses the different elements that make up promoters, including the core promoter and proximal promoter elements. It also covers distal regulatory elements such as enhancers, silencers, insulators, and locus control regions. Enhancers can activate transcription from far away and silencers can repress it. Insulators protect genes from neighboring influences. Locus control regions coordinate expression of entire gene clusters.
This document summarizes eukaryotic transcription by RNA polymerases. It discusses the three types of RNA polymerases (I, II, and III) found in eukaryotic cells, what genes each polymerase transcribes, and the basic stages and mechanisms of transcription (initiation, elongation, termination). It also describes the promoters, processing, and other regulatory elements involved in eukaryotic transcription.
The document discusses the structure and function of eukaryotic transcription factors. It describes several common DNA-binding domains used by transcription factors, including the helix-turn-helix, zinc finger, and basic domains. It also discusses transcriptional activation domains, repressor domains, and dimerization domains. The document provides examples of how transcription is regulated by constitutive factors, phosphorylation, hormones, development factors, and viral proteins.
- The document describes the structures of eukaryotic and prokaryotic genes. It contains diagrams summarizing the key elements and differences between their structures.
- Eukaryotic genes typically contain exons and introns, with introns spliced out of pre-mRNA. They have more regulatory elements than prokaryotes. Prokaryotic genes often exist in polycistronic operons with multiple protein-coding regions on one mRNA.
- Common to both are regulatory sequences that control transcription, untranslated regions, and a protein-coding region. However, eukaryotes add post-transcriptional modifications while prokaryotes can have coupled translation of operon regions.
All eukaryotes have at least three different RNA polymerase (Pol I, II,and III; and plants have a Pol IV & a Pol V). In addition, whereas bacteria require only one additional initiation factor (σ), several initiation factors are required for efficient and promoter-specific initiation in eukaryotes. These are called the general transcription factors (GTFs)
Cells contain three main types of RNA: rRNA, tRNA, and mRNA. rRNA makes up ribosomes, tRNA transports amino acids during protein synthesis, and mRNA directs protein synthesis. Transcription is carried out by RNA polymerases that resemble DNA polymerases. In prokaryotes, transcription initiates at promoter sequences and terminates at specific termination sites. Eukaryotes have multiple RNA polymerases and more complex transcription initiation involving general transcription factors that help recruit the polymerase and direct proper initiation.
Eukaryotic TranscriptionOverall, the process of RNA synthesis in e.pdfmohammadirfan136964
Eukaryotic Transcription
Overall, the process of RNA synthesis in eukaryotes is similar to that of prokaryotes. There are
some real differences, however. For one thing, initial transcripts in eukaryotes contain introns,
which must be removed after transcription (this will be examined later). Eukaryotes also have
three RNA polymerases, instead of just one. Each of these polymerases transcribes a different
class of genes, as outlined in the table below:
Our consideration of eukaryotic transcription will focus on genes transcribed by RNA
polymerase II (known as class II genes). As with prokaryotes, the transcription process can be
broken down into the steps of initiation, elongation, and termination. In eukaryotes, there is also
the additional step of RNA processing, which occurs during and after transcription.
Initiation
Initiation in eukaryotes is much more complex than it is in prokaryotes. Eukaryotic genes must
be much more carefully regulated, because many genes are only expressed in specific cells or
tissues at specific times in the organism\'s life. To achieve this careful regulation, eukaryotes
have evolved a more complicated initiation scheme than prokaryotes. In addition to promoters,
eukaryotic genes also have regulatory regions called enhancers. Both elements (promoter and
enhancer) are required for full, correct expression of eukaryotic genes. As a result of this added
complexity, eukaryotic RNA polymerases do not have anything equivalent to the sigma subunit
found in prokaryotic RNA polymerases. Instead, eukaryotes have groups of transcription factors,
which are proteins, independent of the RNA polymerases, that recognize promoter and enhancer
sequences.
Eukaryotic promoters, like prokaryotic promoters, contain conserved sequences that are
important for initiation. (Eukaryotes, because of their added complexity, tend to have more
conserved sequences in their promoters than do prokaryotes.) One important sequence in most
eukaryotic promoters is found around -30, and has the sequence TATAAA (or something close
to it). This promoter element, known as the TATA Box, is analogous to the -10 element in
prokaryotes. Other promoter sequences vary from gene to gene, but a common one is
GGCCAATCT, otherwise known as the CCAAT Box (for the central bases in the sequence),
which tends to occur around -80.
A group of basal transcription factors helps to initiate transcription of class II genes. Each
member of this group is named \"TFII\" for Transcription Factor, class II genes. The individual
factors are assigned a separate letter designation. For example, TFIID, a factor made of multiple
polypeptides, recognizes and binds to the TATA box. This factor and the other factors (TFIIA,
TFIIB, TFIIE, TFIIF, TFIIH, and TFIIJ) forms a complex on the DNA that recruits RNA
polymerase II to the promoter, and promotes initiation of transcription. These transcription
factors are sufficient to get a basal (minimal) level of transcription. Other transcription .
Gene expression is regulated at multiple levels, including changes to DNA, transcription, RNA processing, mRNA degradation, translation, protein activity, and protein stability. Regulation occurs through factors that activate or repress expression, altering chromatin structure, controlling transcription initiation, splicing mRNA, degrading mRNA, regulating translation, modifying proteins, and marking proteins for degradation. Understanding gene regulation is important for development, differentiation, and cellular adaptation to environmental conditions.
This document summarizes key aspects of gene transcription including:
1. Transcription is important for regulating cellular function and aberrant control can cause disease.
2. In eukaryotes, transcription and translation are separated in space and time, and primary RNA transcripts undergo extensive processing.
3. Prokaryotic transcription involves RNA polymerase recognizing promoters and transcribing DNA into RNA with sigma factors providing specificity. Eukaryotic transcription involves three RNA polymerases and more complex promoters.
The document summarizes eukaryotic transcription and its regulation. It discusses the core promoter elements, pre-initiation complex formation, the three phases of transcription (initiation, elongation, termination), and the role of RNA polymerase and general transcription factors. It also describes mRNA processing events like capping, splicing, and polyadenylation. Finally, it discusses mechanisms of transcriptional regulation including cis-regulatory elements like promoters and enhancers, the role of chromatin structure, and common DNA-binding domains in transcription factors.
According to the central dogma of molecular biology, genetic information usually flows (1) from DNA to DNA during its transmission from generation to generation and (2) from DNA to protein during its phenotypic expression in an organism
Translation and microbial protein productionmithu mehr
This document discusses translation and microbial protein production in bacteria. It begins by describing the structure of tRNAs, including their length, modified nucleotides, and key regions. It then explains the two-step process of decoding mRNA sequences into amino acid sequences, mediated by aminoacyl-tRNA synthetases and the interaction of tRNA anticodons with mRNA codons. Several figures show the structures of ribosomes, translation initiation and elongation factors, and the multi-step process of elongation. The document also discusses termination, energy requirements, rates of translation, and regulation of mRNA translation. Finally, it covers vectors, promoters, and challenges in producing recombinant proteins in E. coli.
Gemma Wean- Nutritional solution for Artemiasmuskaan0008
GEMMA Wean is a high end larval co-feeding and weaning diet aimed at Artemia optimisation and is fortified with a high level of proteins and phospholipids. GEMMA Wean provides the early weaned juveniles with dedicated fish nutrition and is an ideal follow on from GEMMA Micro or Artemia.
GEMMA Wean has an optimised nutritional balance and physical quality so that it flows more freely and spreads readily on the water surface. The balance of phospholipid classes to- gether with the production technology based on a low temperature extrusion process improve the physical aspect of the pellets while still retaining the high phospholipid content.
GEMMA Wean is available in 0.1mm, 0.2mm and 0.3mm. There is also a 0.5mm micro-pellet, GEMMA Wean Diamond, which covers the early nursery stage from post-weaning to pre-growing.
The document summarizes transcription and RNA processing in cells. There is a two step process of transcription and translation required for protein synthesis. Transcription involves synthesizing RNA from a DNA template in the nucleus. Translation occurs in the cytoplasm and converts mRNA into a polypeptide chain. Eukaryotic mRNA undergoes processing including 5' capping, polyadenylation, and splicing of introns from exons before it can be translated. Prokaryotic transcription initiation and termination differ from eukaryotes and involve RNA polymerase binding promoters and terminator sequences.
Prokaryotic transcription involves RNA polymerase binding to promoter sequences on DNA and synthesizing RNA without the need for primers. It proceeds through initiation, elongation, and termination stages. Eukaryotic transcription is more complex, utilizing three RNA polymerases and involving transcription factors, mediator complexes, 5' capping, splicing, and 3' polyadenylation to process mRNA. Alternative splicing allows single genes to code for multiple proteins through different combinations of exons.
This document summarizes transcriptional gene regulation in eukaryotes. It discusses the basic mechanisms of transcription including initiation, elongation, and termination. It describes the role of general transcription factors, promoter elements like TATA boxes, and RNA polymerase in basal transcription. It also explains how distal enhancer elements and transcription factors regulate gene expression by interacting with the promoter and basal transcription machinery. Chromatin structure is also noted to influence transcription. The modular and combinatorial nature of transcriptional control is emphasized.
Transcription factors and their role in plant disease resistanceSachin Bhor
Transcription factors play an important role in regulating plant gene expression and disease resistance. GhWRKY15 is a transcription factor that has been shown to enhance resistance to viruses and fungi in tobacco plants. Overexpression of GhWRKY15 in tobacco increased the expression of pathogenesis-related genes and activated antioxidant enzymes, reducing reactive oxygen species accumulation. GhWRKY15 was also found to affect plant growth and development, with transgenic tobacco plants exhibiting altered stem morphology and accelerated flowering. The presentation discussed the structure, mechanisms and important families of transcription factors in plants, using GhWRKY15 as a case study to illustrate how transcription factors regulate stress responses.
This document discusses transcriptional gene regulation in eukaryotes. It describes how gene expression is controlled through the regulation of transcription, which involves basal transcription factors, proximal promoter elements, distal enhancer and silencer elements, and the binding of transcription factors to cis-regulatory modules. Chromatin structure also influences transcription through modifications that can activate or repress gene expression. Multiple levels of gene regulation allow for fine-tuned and combinatorial control of transcription in eukaryotic cells.
This document discusses various classes of transcriptional regulatory elements. It begins by introducing transcriptional regulation and the basic transcriptional machinery. It then discusses the different elements that make up promoters, including the core promoter and proximal promoter elements. It also covers distal regulatory elements such as enhancers, silencers, insulators, and locus control regions. Enhancers can activate transcription from far away and silencers can repress it. Insulators protect genes from neighboring influences. Locus control regions coordinate expression of entire gene clusters.
This document summarizes eukaryotic transcription by RNA polymerases. It discusses the three types of RNA polymerases (I, II, and III) found in eukaryotic cells, what genes each polymerase transcribes, and the basic stages and mechanisms of transcription (initiation, elongation, termination). It also describes the promoters, processing, and other regulatory elements involved in eukaryotic transcription.
The document discusses the structure and function of eukaryotic transcription factors. It describes several common DNA-binding domains used by transcription factors, including the helix-turn-helix, zinc finger, and basic domains. It also discusses transcriptional activation domains, repressor domains, and dimerization domains. The document provides examples of how transcription is regulated by constitutive factors, phosphorylation, hormones, development factors, and viral proteins.
- The document describes the structures of eukaryotic and prokaryotic genes. It contains diagrams summarizing the key elements and differences between their structures.
- Eukaryotic genes typically contain exons and introns, with introns spliced out of pre-mRNA. They have more regulatory elements than prokaryotes. Prokaryotic genes often exist in polycistronic operons with multiple protein-coding regions on one mRNA.
- Common to both are regulatory sequences that control transcription, untranslated regions, and a protein-coding region. However, eukaryotes add post-transcriptional modifications while prokaryotes can have coupled translation of operon regions.
All eukaryotes have at least three different RNA polymerase (Pol I, II,and III; and plants have a Pol IV & a Pol V). In addition, whereas bacteria require only one additional initiation factor (σ), several initiation factors are required for efficient and promoter-specific initiation in eukaryotes. These are called the general transcription factors (GTFs)
Cells contain three main types of RNA: rRNA, tRNA, and mRNA. rRNA makes up ribosomes, tRNA transports amino acids during protein synthesis, and mRNA directs protein synthesis. Transcription is carried out by RNA polymerases that resemble DNA polymerases. In prokaryotes, transcription initiates at promoter sequences and terminates at specific termination sites. Eukaryotes have multiple RNA polymerases and more complex transcription initiation involving general transcription factors that help recruit the polymerase and direct proper initiation.
Eukaryotic TranscriptionOverall, the process of RNA synthesis in e.pdfmohammadirfan136964
Eukaryotic Transcription
Overall, the process of RNA synthesis in eukaryotes is similar to that of prokaryotes. There are
some real differences, however. For one thing, initial transcripts in eukaryotes contain introns,
which must be removed after transcription (this will be examined later). Eukaryotes also have
three RNA polymerases, instead of just one. Each of these polymerases transcribes a different
class of genes, as outlined in the table below:
Our consideration of eukaryotic transcription will focus on genes transcribed by RNA
polymerase II (known as class II genes). As with prokaryotes, the transcription process can be
broken down into the steps of initiation, elongation, and termination. In eukaryotes, there is also
the additional step of RNA processing, which occurs during and after transcription.
Initiation
Initiation in eukaryotes is much more complex than it is in prokaryotes. Eukaryotic genes must
be much more carefully regulated, because many genes are only expressed in specific cells or
tissues at specific times in the organism\'s life. To achieve this careful regulation, eukaryotes
have evolved a more complicated initiation scheme than prokaryotes. In addition to promoters,
eukaryotic genes also have regulatory regions called enhancers. Both elements (promoter and
enhancer) are required for full, correct expression of eukaryotic genes. As a result of this added
complexity, eukaryotic RNA polymerases do not have anything equivalent to the sigma subunit
found in prokaryotic RNA polymerases. Instead, eukaryotes have groups of transcription factors,
which are proteins, independent of the RNA polymerases, that recognize promoter and enhancer
sequences.
Eukaryotic promoters, like prokaryotic promoters, contain conserved sequences that are
important for initiation. (Eukaryotes, because of their added complexity, tend to have more
conserved sequences in their promoters than do prokaryotes.) One important sequence in most
eukaryotic promoters is found around -30, and has the sequence TATAAA (or something close
to it). This promoter element, known as the TATA Box, is analogous to the -10 element in
prokaryotes. Other promoter sequences vary from gene to gene, but a common one is
GGCCAATCT, otherwise known as the CCAAT Box (for the central bases in the sequence),
which tends to occur around -80.
A group of basal transcription factors helps to initiate transcription of class II genes. Each
member of this group is named \"TFII\" for Transcription Factor, class II genes. The individual
factors are assigned a separate letter designation. For example, TFIID, a factor made of multiple
polypeptides, recognizes and binds to the TATA box. This factor and the other factors (TFIIA,
TFIIB, TFIIE, TFIIF, TFIIH, and TFIIJ) forms a complex on the DNA that recruits RNA
polymerase II to the promoter, and promotes initiation of transcription. These transcription
factors are sufficient to get a basal (minimal) level of transcription. Other transcription .
Gene expression is regulated at multiple levels, including changes to DNA, transcription, RNA processing, mRNA degradation, translation, protein activity, and protein stability. Regulation occurs through factors that activate or repress expression, altering chromatin structure, controlling transcription initiation, splicing mRNA, degrading mRNA, regulating translation, modifying proteins, and marking proteins for degradation. Understanding gene regulation is important for development, differentiation, and cellular adaptation to environmental conditions.
This document summarizes key aspects of gene transcription including:
1. Transcription is important for regulating cellular function and aberrant control can cause disease.
2. In eukaryotes, transcription and translation are separated in space and time, and primary RNA transcripts undergo extensive processing.
3. Prokaryotic transcription involves RNA polymerase recognizing promoters and transcribing DNA into RNA with sigma factors providing specificity. Eukaryotic transcription involves three RNA polymerases and more complex promoters.
The document summarizes eukaryotic transcription and its regulation. It discusses the core promoter elements, pre-initiation complex formation, the three phases of transcription (initiation, elongation, termination), and the role of RNA polymerase and general transcription factors. It also describes mRNA processing events like capping, splicing, and polyadenylation. Finally, it discusses mechanisms of transcriptional regulation including cis-regulatory elements like promoters and enhancers, the role of chromatin structure, and common DNA-binding domains in transcription factors.
According to the central dogma of molecular biology, genetic information usually flows (1) from DNA to DNA during its transmission from generation to generation and (2) from DNA to protein during its phenotypic expression in an organism
Translation and microbial protein productionmithu mehr
This document discusses translation and microbial protein production in bacteria. It begins by describing the structure of tRNAs, including their length, modified nucleotides, and key regions. It then explains the two-step process of decoding mRNA sequences into amino acid sequences, mediated by aminoacyl-tRNA synthetases and the interaction of tRNA anticodons with mRNA codons. Several figures show the structures of ribosomes, translation initiation and elongation factors, and the multi-step process of elongation. The document also discusses termination, energy requirements, rates of translation, and regulation of mRNA translation. Finally, it covers vectors, promoters, and challenges in producing recombinant proteins in E. coli.
Gemma Wean- Nutritional solution for Artemiasmuskaan0008
GEMMA Wean is a high end larval co-feeding and weaning diet aimed at Artemia optimisation and is fortified with a high level of proteins and phospholipids. GEMMA Wean provides the early weaned juveniles with dedicated fish nutrition and is an ideal follow on from GEMMA Micro or Artemia.
GEMMA Wean has an optimised nutritional balance and physical quality so that it flows more freely and spreads readily on the water surface. The balance of phospholipid classes to- gether with the production technology based on a low temperature extrusion process improve the physical aspect of the pellets while still retaining the high phospholipid content.
GEMMA Wean is available in 0.1mm, 0.2mm and 0.3mm. There is also a 0.5mm micro-pellet, GEMMA Wean Diamond, which covers the early nursery stage from post-weaning to pre-growing.
This particular slides consist of- what is hypotension,what are it's causes and it's effect on body, risk factors, symptoms,complications, diagnosis and role of physiotherapy in it.
This slide is very helpful for physiotherapy students and also for other medical and healthcare students.
Here is the summary of hypotension:
Hypotension, or low blood pressure, is when the pressure of blood circulating in the body is lower than normal or expected. It's only a problem if it negatively impacts the body and causes symptoms. Normal blood pressure is usually between 90/60 mmHg and 120/80 mmHg, but pressures below 90/60 are generally considered hypotensive.
International Cancer Survivors Day is celebrated during June, placing the spotlight not only on cancer survivors, but also their caregivers.
CANSA has compiled a list of tips and guidelines of support:
https://cansa.org.za/who-cares-for-cancer-patients-caregivers/
Hypertension and it's role of physiotherapy in it.Vishal kr Thakur
This particular slides consist of- what is hypertension,what are it's causes and it's effect on body, risk factors, symptoms,complications, diagnosis and role of physiotherapy in it.
This slide is very helpful for physiotherapy students and also for other medical and healthcare students.
Here is summary of hypertension -
Hypertension, also known as high blood pressure, is a serious medical condition that occurs when blood pressure in the body's arteries is consistently too high. Blood pressure is the force of blood pushing against the walls of blood vessels as the heart pumps it. Hypertension can increase the risk of heart disease, brain disease, kidney disease, and premature death.
Chandrima Spa Ajman is one of the leading Massage Center in Ajman, which is open 24 hours exclusively for men. Being one of the most affordable Spa in Ajman, we offer Body to Body massage, Kerala Massage, Malayali Massage, Indian Massage, Pakistani Massage Russian massage, Thai massage, Swedish massage, Hot Stone Massage, Deep Tissue Massage, and many more. Indulge in the ultimate massage experience and book your appointment today. We are confident that you will leave our Massage spa feeling refreshed, rejuvenated, and ready to take on the world.
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This particular slides consist of- what is Pneumothorax,what are it's causes and it's effect on body, risk factors, symptoms,complications, diagnosis and role of physiotherapy in it.
This slide is very helpful for physiotherapy students and also for other medical and healthcare students.
Here is a summary of Pneumothorax:
Pneumothorax, also known as a collapsed lung, is a condition that occurs when air leaks into the space between the lung and chest wall. This air buildup puts pressure on the lung, preventing it from expanding fully when you breathe. A pneumothorax can cause a complete or partial collapse of the lung.
PET CT beginners Guide covers some of the underrepresented topics in PET CTMiadAlsulami
This lecture briefly covers some of the underrepresented topics in Molecular imaging with cases , such as:
- Primary pleural tumors and pleural metastases.
- Distinguishing between MPM and Talc Pleurodesis.
- Urological tumors.
- The role of FDG PET in NET.
Comprehensive Rainy Season Advisory: Safety and Preparedness Tips.pdfDr Rachana Gujar
The "Comprehensive Rainy Season Advisory: Safety and Preparedness Tips" offers essential guidance for navigating rainy weather conditions. It covers strategies for staying safe during storms, flood prevention measures, and advice on preparing for inclement weather. This advisory aims to ensure individuals are equipped with the knowledge and resources to handle the challenges of the rainy season effectively, emphasizing safety, preparedness, and resilience.
We are one of the top Massage Spa Ajman Our highly skilled, experienced, and certified massage therapists from different corners of the world are committed to serving you with a soothing and relaxing experience. Luxuriate yourself at our spas in Sharjah and Ajman, which are indeed enriched with an ambiance of relaxation and tranquility. We could confidently claim that we are one of the most affordable Spa Ajman and Sharjah as well, where you can book the massage session of your choice for just 99 AED at any time as we are open 24 hours a day, 7 days a week.
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2024 HIPAA Compliance Training Guide to the Compliance OfficersConference Panel
Join us for a comprehensive 90-minute lesson designed specifically for Compliance Officers and Practice/Business Managers. This 2024 HIPAA Training session will guide you through the critical steps needed to ensure your practice is fully prepared for upcoming audits. Key updates and significant changes under the Omnibus Rule will be covered, along with the latest applicable updates for 2024.
Key Areas Covered:
Texting and Email Communication: Understand the compliance requirements for electronic communication.
Encryption Standards: Learn what is necessary and what is overhyped.
Medical Messaging and Voice Data: Ensure secure handling of sensitive information.
IT Risk Factors: Identify and mitigate risks related to your IT infrastructure.
Why Attend:
Expert Instructor: Brian Tuttle, with over 20 years in Health IT and Compliance Consulting, brings invaluable experience and knowledge, including insights from over 1000 risk assessments and direct dealings with Office of Civil Rights HIPAA auditors.
Actionable Insights: Receive practical advice on preparing for audits and avoiding common mistakes.
Clarity on Compliance: Clear up misconceptions and understand the reality of HIPAA regulations.
Ensure your compliance strategy is up-to-date and effective. Enroll now and be prepared for the 2024 HIPAA audits.
Enroll Now to secure your spot in this crucial training session and ensure your HIPAA compliance is robust and audit-ready.
https://conferencepanel.com/conference/hipaa-training-for-the-compliance-officer-2024-updates
Can coffee help me lose weight? Yes, 25,422 users in the USA use it for that ...nirahealhty
The South Beach Coffee Java Diet is a variation of the popular South Beach Diet, which was developed by cardiologist Dr. Arthur Agatston. The original South Beach Diet focuses on consuming lean proteins, healthy fats, and low-glycemic index carbohydrates. The South Beach Coffee Java Diet adds the element of coffee, specifically caffeine, to enhance weight loss and improve energy levels.
TEST BANK FOR Health Assessment in Nursing 7th Edition by Weber Chapters 1 - ...rightmanforbloodline
TEST BANK FOR Health Assessment in Nursing 7th Edition by Weber Chapters 1 - 34.
TEST BANK FOR Health Assessment in Nursing 7th Edition by Weber Chapters 1 - 34.
TEST BANK FOR Health Assessment in Nursing 7th Edition by Weber Chapters 1 - 34.
TEST BANK FOR Health Assessment in Nursing 7th Edition by Weber Chapters 1 - ...
13-miller-chap-7b-lecture.ppt
1. Chap. 7 Transcriptional Control of Gene
Expression (Part B)
Topics
• RNA Polymerase II Promoters and General Transcription
Factors
• Regulatory Sequences in Protein-coding Genes and the Proteins
Through Which They Function
Goals
• Learn about transcription
control elements and methods
of promoter analysis.
• Learn how the RNA
polymerase II pre-initiation
complex assembles at a
promoter.
• Learn about the structures of
eukaryotic transcription
factors.
Transcriptionally active polytene
chromosomes
2. Overview of Eukaryotic Promoters
The promoter of a eukaryotic gene can be defined as a sequence
that sets the transcription start site for RNA polymerase. Strong
RNA Pol II promoters contain an A/T rich sequence known as the
TATA box located 26-31 bp upstream of the start site (Fig.
7.14). Other genes have alternative sequence elements known as
initiators (Inr) which also serve as promoters that set the RNA Pol
II start site. Finally, CG-rich repeat sequences (CpG islands) are
used by RNA Pol II as promoters in 60-70% of genes. Most of
these genes are weakly expressed.
3. Transcription Initiation by RNA Pol II
RNA Pol II requires general TFs in addition to tissue-specific
transcription factors for transcription of most genes in vivo.
General TFs position RNA Pol II at start sites and assist the
enzyme in melting promoter DNA. General TFs are highly
conserved across species. The general TFs used at TATA box
promoters are TFIIA, B, D, etc. TFIIA is required for
transcription only in vivo. TFIID consists of TBP (TATA box
binding protein) and 13 TBP-associated factors (TAFs). While
the complete TFIID complex is required for transcription in
vivo, only TBP is required in vitro. Formation of the pre-
initiation complex in vitro is illustrated in the next two slides
(Fig. 7.17).
4. Pol II Pre-initiation Complex Formation (I)
The sequential steps leading to
the assembly of the RNA Pol
II pre-initiation complex in
vitro are shown in Fig. 7.17.
First, TBP binds to the TATA
box and bends DNA near the
promoter. Next, TFIIB binds,
and then a complex between
Pol II and TFIIF loads onto
the promoter. TFIIF positions
the Pol II active site at the
mRNA start site. TFIIF also
possesses histone acetylase
activity and helps maintain
chromatin at the promoter in
an uncondensed state. TFIIE
then binds creating a TFIIH
docking site (next slide).
5. Pol II Pre-initiation Complex Formation (II)
With the addition of TFIIH,
the assembly of the pre-
initiation complex is complete.
Subsequently, one subunit of
TFIIH melts DNA at the
promoter, obtaining energy by
ATP hydrolysis. Pol II then
begins transcribing the
mRNA. Another subunit of
TFIIH phosphorylates the Pol
II CTD, making Pol II highly
processive. In vitro, all
factors except TBP dissociate
from the promoter region
after Pol II moves
downstream. Tissue-specific
TFs bound to enhancers and
promoter-proximal elements
also play important roles in
transcription initiation in vivo.
6. Linker Scanning Mutagenesis Analysis of
Gene Regulatory Sites
A technique called linker
scanning mutagenesis
commonly is used to
identify transcription
control regions known as
promoter-proximal
elements that lie within
100-200 bp of a start
site Fig. 7.21. These
elements are required for
transcription but are not
directly involved in start
site selection. Large
changes in the locations of
these elements can
interfere with
transcription. Promoter-
proximal elements are
commonly important for
cell type-specific
transcription of genes.
7. Summary of Gene Control Elements
A spectrum of control elements regulate transcription by RNA Pol
II in eukaryotes. Their locations relative to the exons of a gene
are summarized in Fig. 7.22. Enhancers are transcription control
elements of 50-200 bp in length that can act from sites distant
from the regulated gene. They often are important for cell type-
specific regulation of transcription. Enhancers can be positioned
upstream, downstream, or even within introns while still being
functional. They further may be located 50 kb away from a
transcription start site. Enhancers are composed of ~6-10 bp
DNA modules that are bound by transcription factors. Promoter-
proximal elements typically need to be with ~200 bp of the
transcription start site to be functional. Yeast genes usually
contain only upstream activating sequences (UAS) and a TATA box
for control of transcription. UASs act similarly to enhancers and
promoter-proximal elements in higher eukaryotes.
8. DNase I Footprinting
The human genome encodes ~2,000 transcription factors (TFs). A
method (DNase I footprinting) for determining locations of TF
binding sites in DNA is shown in Fig. 7.23. First, DNA labeled on
one strand is incubated with the protein of interest. Then the
complex is treated with a small amount of DNase I, which cleaves
DNA where it is not masked by the TF (Fig. 7.23a). A control
DNA sample lacking the TF is treated under parallel conditions.
Finally, the banding patterns from the two samples are compared
by gel electrophoresis to locate the "footprint" region where the
TF has shielded the DNA from cleavage (Fig. 7.23b).
9. Analysis of TF Activity in vivo
TFs can be assayed for their
ability to bind to DNA control
elements and regulate gene
expression by in vivo
transfection assays (Fig.
7.25). In this method, a
plasmid encoding the putative
TF (protein X) is introduced
into an animal cell along with
a second vector encoding a
reporter gene and the
putative protein X binding
site. If protein X binds to
the site and is a transcription
activator, then the reporter
gene is switched on. Note
that the cells must not
express protein X per se.
10. Modular Structure of Activators I
Transcription
activators are modular
proteins composed of
distinct functional
domains. They typically
contain both DNA-
binding and activation
domains. A deletion
analysis performed
with the yeast GAL4
activator illustrating
that it contains these
two types of domains is
shown in Fig. 7.26.
The N-terminal amino
acids of GAL4
modulate DNA binding,
whereas its C-terminal
region contains an
activation domain.
11. Modular Structure of Activators II
Functional domains in activators are joined by flexible protein linker
sequences (Fig. 7.27). Due to the presence of linkers, the spacing
and location of DNA control elements often can be shifted without
interfering with DNA binding and regulation of promoters. The
evolution of gene control regions through shuffling of DNA binding
sequences between genes may have been favored due to the lack of
strong requirements for control element spacing and location. The
evolution of new activator protein genes through domain swapping
has probably also been facilitated by linker sequences.
Note, that transcription of some genes is controlled by repressors.
Repressors typically contain a DNA-binding domain and a repression
domain. The repression domain interacts with other TFs at a control
site, inhibiting their activity. The inactivation of a repressor can
lead to constitutive expression of the gene it controls.
12. Secondary Structure Motifs
Secondary structure motifs are evolutionarily conserved
collections of secondary structure elements which have a defined
conformation. They also have a consensus sequence because the
aa sequence ultimately determines structure. A given motif can
occur in a number of proteins where it carries out the same or
similar functions. Some well known examples such as the coiled-
coil, EF hand/helix-loop-helix, and zinc-finger motifs are
illustrated in Fig. 3.9. These motifs typically mediate protein-
protein association, calcium/DNA binding, and DNA or RNA
binding, respectively.
13. Helix-turn-helix TFs
DNA-binding proteins bind
specifically to DNA via non-
covalent interactions. a-
helices are one of the most
common types of DNA-
binding sequences (Fig.
7.28). The side-chains of
residues within the a-helix
often bind to the surfaces
of bases exposed in the
major groove of double-
helical DNA. Binding to
phosphates and bases in the
minor groove typically is less
important. One of the most
common DNA-binding
structure motifs is the
helix-turn-helix.The second
helix in this motif (the DNA
recognition helix) typically
binds to a specific sequence of bases in DNA. The recognition
helices in the dimeric bacteriophage 434 repressor are
indicated with asterisks in Fig. 7.28a. Helix-turn-helix TFs
are common in bacteria.
14. Zinc-finger TFs
The most common DNA-
binding motif in human and
multicellular animal TFs is the
zinc finger. Two types of zinc
finger TFs are discussed
here--C2H2 zinc finger TFs
(Fig. 7.29a) and C4 zinc
finger TFs (Fig. 7.29b). Most
TFs that contain C2H2 zinc
fingers are monomeric. Its 2
cysteine and 2 histidine
residues bind to zinc ions
(Zn2+) (Fig. 7.29a), and the
a-helix containing the 2
histidines binds to bases in
the major groove. Much less
common are TFs containing C4 zinc fingers. Most TFs containing
this motif are dimeric. Nuclear receptors, which bind steroid
hormones and other compounds, contain this motif. The
glucocorticoid receptor is shown in Fig. 7.29b. Zinc ions are
bound to the DNA recognition helix of this motif, which contacts
bases in the major groove.
15. Leucine-zipper TFs
Leucine-zipper TFs contain extended a-helices wherein every 7th
amino acid is leucine. This periodicity creates a nonpolar face on
one side of the helix that is ideal for dimerization with another
such protein via a coiled-coil motif (Fig. 7.29c). So-called basic
zipper (bZip) TFs have a similar structure except that some
leucines are replaced by other nonpolar amino acids. The N-
terminal ends of both leucine-zipper and bZip proteins contain
basic amino acids that interact with bases in the major groove
(Fig. 7.29c). Leucine zipper proteins are now considered to be a
subclass of bZip proteins.
Another class of TF, the
basic helix-loop-helix (bHLH)
proteins are similar to bZip
proteins, but contain a loop
between the DNA recognition
helix and the coiled-coil
region (Fig. 7.29d). bZip and
bHLH proteins commonly
form heterodimeric TFs.
Basic residues
16. Regulation of TF Activity
Many TFs bind ligands or co-activator/co-repressor proteins that
modulate their structure and activity. In the yeast GAL4 TF, its
"acidic activation domain" adopts an essentially random-coil
structure until it binds to a co-activator protein. This control
mechanism keeps the TF turned off until the appropriate cofactor
is present in the nucleus. Nuclear receptors such as the estrogen
receptor contain partially structured activation domains that
undergo conformational changes to the active structural state on
binding to hormone (e.g., estrogen) (Fig. 7.30b). In the active
conformation, the estrogen receptor can bind to co-activator
proteins required for transcription. The estrogen antagonist,
tamoxifen, that is used in breast cancer therapy, locks the
receptor in its inactive conformation that cannot bind co-activator
proteins (Fig. 7.30c).
17. Heterodimeric TFs
The formation of heterodimeric
TFs by bZip and bHLH TFs is
important in increasing the
complexity of transcriptional
regulation of genes. Sometimes
monomers within the
heterodimer recognize the same
DNA element, but have
different activation domains
(Fig. 7.31a). Different
regulatory responses result from
the different combinations of
activation domains bound to the
site. In other cases, monomers
within the heterodimer bind
different DNA elements (Fig.
7.31b). Each site then binds a
unique species of heterodimer.
Lastly, an inhibitory factor that
binds to only one type of
monomer will only affect sites
used by that monomer (Fig.
7.31c).
18. Cooperative Binding of TFs to DNA
In many cases, a TF will bind to a DNA element with high
affinity only when complexed with a second TF (Fig. 7.32a).
Such cooperative binding to DNA adds further complexity to
gene regulation. Namely, a certain TF will bind to its DNA
element only if its interacting partner also is expressed in that
cell type. In addition, expression levels of interacting TFs can
be varied between tissues to adjust gene transcription rates.
19. Multiprotein Complexes at Enhancers
Enhancers typically contain several DNA sequence elements that
are recognized by different DNA binding proteins (e.g., the ß-
interferon enhancer, Fig. 7.33). The resulting nucleoprotein
complex is called an enhanceosome. Enhancers often are involved
in tissue-specific control of transcription. Given the complex
structures of enhanceosomes, it is easy to see how the absence
of even one of the factors that bind to the enhancer in a certain
tissue could change the expression level of the gene.