The document summarizes the cell cycle and its regulation. It describes the main stages of the cell cycle - interphase consisting of G1, S, and G2 phases and the M phase. Key regulators of the cell cycle include cyclins, cyclin-dependent kinases, and checkpoints like G1, G2, and M that ensure fidelity of DNA replication and chromosome segregation. Dysregulation of these processes can lead to genomic instability and cancer.
here in this presentation you will be studying about cell cycle , cell checkpoints , cell cycle regulators etc .
very informative slides by anshika singh
a deeply explained process of cell division, for understanding it thoroughly. i tried to put in all the information i knew and collected. i hope it is helpful or you.
here in this presentation you will be studying about cell cycle , cell checkpoints , cell cycle regulators etc .
very informative slides by anshika singh
a deeply explained process of cell division, for understanding it thoroughly. i tried to put in all the information i knew and collected. i hope it is helpful or you.
A detailed description of molecular level of cell cycle. Its regulation by different checkpoints. The Structure and Function of MPF. Description of MPF discovery.
This slide describes the various stages of the Eukaryotic cell cycle. The diagrams included here explains the various changes that take place during the mitotic division of a eukaryotic cell.
Basic Cell cycle regulation suitable for undergraduate students.
This presentation has been started from the basics to enable easy understanding. It covers all the details of cell cycle regulation in yeast as well as higher eukaryotes.
Cell cycle & Mitosis presentation to help understand the basic concepts related to the topic. This topic is included in the Maharashtra Board curriculum for XIth Std Biology paper. All videos inserted in this powerpoint have their respective copyrights. Unauthorized distribution and copying of the same is prohibited
The cell cycle, or cell-division cycle, is the series of events that take place in a cell leading to duplication of its DNA (DNA replication) and division of cytoplasm and organelles to produce two daughter cells.
this presentation has detailed information on cell cycle. it includes steps as well as how the proteins take part in cell cycle.
i have also added information on some experiments that were carried out.
happy studying :)
A detailed description of molecular level of cell cycle. Its regulation by different checkpoints. The Structure and Function of MPF. Description of MPF discovery.
This slide describes the various stages of the Eukaryotic cell cycle. The diagrams included here explains the various changes that take place during the mitotic division of a eukaryotic cell.
Basic Cell cycle regulation suitable for undergraduate students.
This presentation has been started from the basics to enable easy understanding. It covers all the details of cell cycle regulation in yeast as well as higher eukaryotes.
Cell cycle & Mitosis presentation to help understand the basic concepts related to the topic. This topic is included in the Maharashtra Board curriculum for XIth Std Biology paper. All videos inserted in this powerpoint have their respective copyrights. Unauthorized distribution and copying of the same is prohibited
The cell cycle, or cell-division cycle, is the series of events that take place in a cell leading to duplication of its DNA (DNA replication) and division of cytoplasm and organelles to produce two daughter cells.
this presentation has detailed information on cell cycle. it includes steps as well as how the proteins take part in cell cycle.
i have also added information on some experiments that were carried out.
happy studying :)
This presentation on "Cell Cycle regulation" takes you to the cell cycle describing the stages and checkpoints involved providing some of the evidences of cell cycle regulation. Then we will move to cyclins and cyclin dependent kinases and the mechanism they follow.
This journey in regulation of cell cycle will take a halt after a general discussion of positive and negative cell cycle regulators.
Thankyou.
Molecular event during Cell cycle By KK Sahu SirKAUSHAL SAHU
WHAT IS CELL?
WHAT IS CELL DIVISION OR CELL CYCLE?
WHY DO CELL DIVIDE?
HISTORY
CELL CYCLE
INTERPHASE
M-PHASE
MOLECULAR EVENT DURING CELL CYCLE AND CELL REGULATION
TYPES OF CELL DIVISION
IMPORTANCE OF CELL DIVISION
ABNORMALTIES OF CELL CYCLE
REFRENCES
The phenomenon of signal transduction, also known as cell signaling, pertains to the intricate mechanisms that facilitate the transfer of biological information between cells. The effective coordination of diverse specialized cell types in various tissues and organs is a prerequisite for the proper functioning of complex multicellular organisms, necessitating intercellular communication. This communication must be continuous and dynamic to maintain coordination. Additionally, cell signaling pathways play a crucial role in the mechanisms of action of numerous drugs, including both local and general anesthetics. Consequently, a fundamental understanding of cell signaling mechanisms is imperative for comprehending various pathophysiologic and pharmacologic mechanisms.
This presentation on "Cell Cycle regulation" takes you to the cell cycle describing the stages and checkpoints involved providing some of the evidences of cell cycle regulation. Then we will move to cyclins and cyclin dependent kinases and the mechanism they follow.
This journey in regulation of cell cycle will take a halt after a general discussion of positive and negative cell cycle regulators.
Thankyou.
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
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Prix Galien International 2024 Forum ProgramLevi Shapiro
June 20, 2024, Prix Galien International and Jerusalem Ethics Forum in ROME. Detailed agenda including panels:
- ADVANCES IN CARDIOLOGY: A NEW PARADIGM IS COMING
- WOMEN’S HEALTH: FERTILITY PRESERVATION
- WHAT’S NEW IN THE TREATMENT OF INFECTIOUS,
ONCOLOGICAL AND INFLAMMATORY SKIN DISEASES?
- ARTIFICIAL INTELLIGENCE AND ETHICS
- GENE THERAPY
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- ETHICAL CHALLENGES IN LIFE SCIENCES
- Prix Galien International Awards Ceremony
Title: Sense of Taste
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
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MANAGEMENT OF ATRIOVENTRICULAR CONDUCTION BLOCK.pdfJim Jacob Roy
Cardiac conduction defects can occur due to various causes.
Atrioventricular conduction blocks ( AV blocks ) are classified into 3 types.
This document describes the acute management of AV block.
2. • The cell cycle or cell-division cycle is the series of
events that take place in a cell leading to its
division and duplication of its DNA to produce
daughter cells.
• There are two types of cell division.
– Mitosis
• Growth and repair
• Produces diploid cells identical to each other and the parent
cell
– Meiosis
• Sexual reproduction
• Produces haploid cells different to each other and the parent
cell.
Somatic cells
Germ cells
3. Eukaryotic Cell Populations
Germ cells -Unlimited proliferation by meiotic division.
(Unlike cancer cells, these cells form immortal cell lines through
meiotic division)
Stem cells -These cells have two functions.
Proliferation & Differentiation
(Unlike cancer cells, these cells can only pass through a limited
number of cell cycles)
Partially differentiated cells - These have a limited capacity for
proliferation, and their daughter cells are fully differentiated with
no proliferative ability.
Fully differentiated cells -These cells never proliferate.
6. Prophase
• The nuclear membrane
and endoplasmic
reticulum disappear.
• The chromosomes
shorten and thicken.
• Centrosomes move
towards opposite poles.
• The nucleolus disappears.
• Spindle cells form from
the poles to the center.
7. Metaphase
• The chromosomes
shorten and thicken
further.
• Sister chromatids are
kept together using
centromeres.
• The chromosomes are
arranged side-by-side in
a row in the equatorial
plane.
• The chromosomes hold
on to spindle cells with
their centromeres.
8. Anaphase
• The contraction and
relaxation movements
of spindle cells break
the centromeres that
lock the chromatids
together.
• The sister chromatids
are separated from
each other and are
moved to opposite
poles.
9. Telophase
• The chromosomes stop moving.
• The chromosomes unwind their
helices and become chromatins.
• The nucleolus reappears.
• RNA and protein syntheses
start.
• Spindle cells disappear.
• The nuclear membrane forms,
and the endoplasmic reticulum
takes on a shape again.
• Vital events restart in the cell.
• Cytogenesis occurs, and division
finishes.
10. Interphase
• The interphase is the preparation phase for
the redivision of a cell.
• It is the longest phase of the eukaryotic cell
cycle.
• The interphase is divided into THREE stages.
(G0/G1, S, G2)
11.
12. G0 phase
• Most cells in an adult are not in the process of
cell division.
• They enter an inactive period called G0, a
phase outside of the cell cycle.
• Mitogens or growth factors can, however,
induce cells in G0 to re-enter the cell cycle.
13. G1 Phase (Gap1)
• This occurs just after cytogenesis.
• This is the stage where matter transportation,
synthesis, lysis reactions, organelle
production, RNA synthesis and tissue
functions continue at their highest levels.
• It is the longest stage.
14. S Phase (Synthesis)
• DNA is duplicated and the number of
chromatins doubles (Replication).
• The most intense protein synthesis is
performed at this stage.
• The order of centromere duplication is
observed.
15. G2 Phase (Gap2)
• Enzymes related to division are synthesized.
• The number of organelles increases.
• DNA synthesis finishes, but RNA synthesis
continues.
• Centrosome synthesis finishes, and these
centrosomes start moving towards opposite
poles.
16. • The most radiosensitive stages during the cell
cycle are the early G2 and M stages
– The radiosensitivity of a cell is four-fold greater
during the mitotic phase than during the
interphase.
• Radioresistance is high in the S, late G1 and
G0 phases.
– The resistance of the S phase is due to the large
amounts of synthesis enzymes present, which
have the ability to rapidly repair DNA.
17. CHECK POINTS
• Cell cycle checkpoints, a series of biochemical
signaling pathways that sense and induce a
cellular response to DNA damage, are
important for maintaining the integrity of the
genome.
• There are 3 important check points
– G1 check point
– G2 check point
– M check point
18. • The G1 checkpoint leads to the arrest of the
cell cycle in response to DNA damage,
ensuring that DNA damage is not replicated
during S phase.
• The G2 checkpoint leads to the arrest of the
cell cycle in response to damaged and/or
unreplicated DNA to ensure proper
completion of S phase.
• The M checkpoint leads to the arrest of
chromosomal segregation in response to
misalignment on the mitotic spindle.
19.
20. Tim Hunt Paul Nurse Lee Hartwell
Nobel Prize in Physiology or Medicine in 2001
The prize was received for studies on the regulation of the cell cycle during which
the cyclins were discovered.
21. • The components of the checkpoints are
proteins that act as DNA damage
sensors, signal transducers, or effectors.
• Disruption of checkpoint function leads
to genomic and chromosomal instability
leading to mutations that can induce
carcinogenesis.
22. • The passage of the cell through the different
phases of the cell cycle is coordinated and
regulated by a set of proteins called cyclins
and their associated cyclin- dependent
kinases (cdks).
• Cyclins are regulatory subunits of their cdks.
23. • Cyclins were so named because of the cyclical
changes in their concentrations that occur
over a series of cell divisions.
• The concentration of cyclin protein is
dependent on the transcription of its gene
and by subsequent regulated protein
degradation.
24.
25. • The cyclin–cdk complexes exert their
effect by phosphorylating target proteins
• Binding of a cyclin to its cdk partner,
cyclin induces a conformational change
in the catalytic subunit of the cdk
revealing its active site.
• The concentration of cdks does not
fluctuate during the cell cycle.
26. • The pairing of cyclins to the cdks is highly
specific.
–Cyclin D - cdks 4/6
–Cyclin E - cdk2
–Cyclin A - cdk2
–Cyclins A,B - cdk1
27.
28. Cyclin D is the first cyclin to be synthesized.
• Cyclin D - cdks 4/6 drives through G1.
• Cyclin E - cdk2 G1 to S phase transition.
• Cyclin A–cdk2 S phase progression.
• Cyclins A,B–cdk1 G2 & G2 to M phase
transition.
29. G1 Check point
• The retinoblastoma (RB) protein is an important
target of cyclin D–cdks 4/6 and a key regulator of
the G1 to S phase transition.
• RB exerts its effects by protein–protein
interactions with the E2F transcription factor and
HDACs.
Hypophosphorylated RB
inactivates E2F and
recruits HDACs.
30. • The activity of RB is regulated by phosphorylation via different
cyclins–cdks.
• Signaling pathway for the growth factor EGF results in the
transcriptional activation of the cyclin D gene and allows
progression through the restriction point.
Repression is relieved for some genes such as cyclin E
31. Phosphorylated RB releases E2F leading to Expression of its
target genes, such as cyclin A, thymidylate synthase, and
dihydrofolate reductase, that are important for S phase
32.
33. G2 Check point
• The G2 checkpoint blocks entry into M phase
in cells that have incurred DNA damage in
previous phases or have not correctly
completed S phase.
• The G2 checkpoint is induced by DNA damage
and aberrant DNA synthesis and blocks entry
into M phase.
• Specific Cdc25s (type B and C) are important
in the G2–M phase transition.
34.
35.
36. • There is also a decatenation G2 checkpoint
that is involved chromatid separation during
anaphase of mitosis.
• Topoisomerase II, an enzyme that can release
torsional stress by making double-strand DNA
breaks to allow unwinding, is key in the
decatenation G2 checkpoint.
37.
38. Mitotic Check point
• The mitotic checkpoint (also known as the spindle assembly
checkpoint) is a signaling cascade that ensures correct
chromosomal segregation during mitosis and the production of
two genetically identical nuclei.
(Prevents mis-segregation of chromosomes during anaphase)
• The Aurora kinases (A, B, and C) regulate important aspects of
mitosis, including chromosome segregation and the spindle
checkpoint.
• They are serine/threonine kinases that phosphorylate target
proteins, which play a role in chromosome structure and
spindle assembly.
39.
40. Mechanisms of cdk regulation
• Cdks are regulated by association with cyclins,
inhibitors, and by activating and inhibitory
phosphorylation.
47. • Four stages: G1, S phase, G2, and M phase.
• G1, S, and G2 make up the part of the cycle called
interphase.
• The genetic material of a cell is replicated in S
phase (DNA synthesis).
• M phase involves the partitioning of the cell to
produce two daughter cells and includes mitosis
and cytokinesis.
• G1 and G2 are ‘gaps’ preceding the S and M
phases during which time the cell prepares for
the next phase.
48. • Aurora kinase A
– Localizes to centrosomes during interphase
– Upregulated at the beginning of mitosis and relocates to the
spindle poles and spindle microtubules
– Role in centrosome maturation and assembly of the spindle
apparatus
• Aurora kinase B activity is highest later in mitosis.
• Role in bipolar spindle attachment to chromosomal
centromeres, and the spindle checkpoint and monitoring of
chromosomal segregation and cytokinesis.
• Aurora kinase C is active during late mitosis and localizes to
spindle poles.
Editor's Notes
For instance, human fibroblast cells divide approximately 50 times in cell lines. After that, they cannot divide, regardless of the nutritive conditions present.
Differentiated normal cells, in contrast to immortal cancer cell lines, have a biological timer that counts the number of cell divisions. When a certain number of divisions have occurred, the cell cannot divide any further.
Cells that lose their ability to divide continue with their functions and life activities
(e.g., muscle and nerve cells still function at this stage)
In the G0 phase, some genes in the DNA are covered with various proteins; i.e., the DNA is programmed.
Dividable cell growth occurs during this stage.
Nobel Prize in Physiology or Medicine in 2001
The prize was received for studies on the regulation of the cell cycle during which the
cyclins were discovered.
Cyclin D plays a role in the regulation of expression of the cyclin E gene.
Histone deacetylase, dimerization partner(associated subunit)
signaling pathway for the growth factor EGF results in the transcriptional activation of the cyclin D gene and allows progression through the restriction point.
Partial phosphorylation of RB by cyclin D–cdk4 causes a conformational change, and release of HDAC but not E2F/DP.
Repression is relieved for some genes such as cyclin E (top) but not for E2F target genes
Expression of its target genes, such as cyclin A, thymidylate synthase, and dihydrofolate reductase, that are important for S phase
which facilitates transcription and cell cycle progression into S phase.
Cdc25 is then unable to remove inhibitory phosphate groups and activate cdks.
Activation of the G2 checkpoint results in the inhibition of Cdc25s by Chk1/2.
in detangling intertwined daughter chromatids after DNA synthesis. This process enables
STK15, STK12, and STK13
They are serine/threonine kinases that phosphorylate target proteins, many of which play a role in chromosome structure and spindle assembly.
cdk-activating kinase (CAK).
The precise temporal regulation of the Aurora kinases is regulated by phosphorylation, protein inhibitors, and targeted degradation.