CDKN2C | |||||||||||||||||||||||||||||||||||||||||||||||||||
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Aliases | CDKN2C , INK4C, p18, p18-INK4C, cyclin-dependent kinase inhibitor 2C, cyclin dependent kinase inhibitor 2C | ||||||||||||||||||||||||||||||||||||||||||||||||||
External IDs | OMIM: 603369; MGI: 105388; HomoloGene: 966; GeneCards: CDKN2C; OMA:CDKN2C - orthologs | ||||||||||||||||||||||||||||||||||||||||||||||||||
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Wikidata | |||||||||||||||||||||||||||||||||||||||||||||||||||
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Cyclin-dependent kinase 4 inhibitor C is an enzyme that in humans is encoded by the CDKN2C gene. [5] [6] [7]
The protein encoded by this gene is a member of the INK4 family of cyclin-dependent kinase inhibitors. This protein has been shown to interact with CDK4 or CDK6, and prevent the activation of the CDK kinases, thus function as a cell growth regulator that controls cell cycle G1 progression. Ectopic expression of this gene was shown to suppress the growth of human cells in a manner that appears to correlate with the presence of a wild-type RB1 function. Studies in the knockout mice suggested the roles of this gene in regulating spermatogenesis, as well as in suppressing tumorigenesis. Two alternatively spliced transcript variants of this gene, which encode an identical protein, have been reported. [7]
CDKN2C has been shown to interact with Cyclin-dependent kinase 4 [5] [8] and Cyclin-dependent kinase 6. [5] [8] [9]
Cyclin-dependent kinases (CDKs) are a predominant group of serine/threonine protein kinases involved in the regulation of the cell cycle and its progression, ensuring the integrity and functionality of cellular machinery. These regulatory enzymes play a crucial role in the regulation of eukaryotic cell cycle and transcription, as well as DNA repair, metabolism, and epigenetic regulation, in response to several extracellular and intracellular signals. They are present in all known eukaryotes, and their regulatory function in the cell cycle has been evolutionarily conserved. The catalytic activities of CDKs are regulated by interactions with CDK inhibitors (CKIs) and regulatory subunits known as cyclins. Cyclins have no enzymatic activity themselves, but they become active once they bind to CDKs. Without cyclin, CDK is less active than in the cyclin-CDK heterodimer complex. CDKs phosphorylate proteins on serine (S) or threonine (T) residues. The specificity of CDKs for their substrates is defined by the S/T-P-X-K/R sequence, where S/T is the phosphorylation site, P is proline, X is any amino acid, and the sequence ends with lysine (K) or arginine (R). This motif ensures CDKs accurately target and modify proteins, crucial for regulating cell cycle and other functions. Deregulation of the CDK activity is linked to various pathologies, including cancer, neurodegenerative diseases, and stroke.
p21Cip1, also known as cyclin-dependent kinase inhibitor 1 or CDK-interacting protein 1, is a cyclin-dependent kinase inhibitor (CKI) that is capable of inhibiting all cyclin/CDK complexes, though is primarily associated with inhibition of CDK2. p21 represents a major target of p53 activity and thus is associated with linking DNA damage to cell cycle arrest. This protein is encoded by the CDKN1A gene located on chromosome 6 (6p21.2) in humans.
INK4 is a family of cyclin-dependent kinase inhibitors (CKIs). The members of this family (p16INK4a, p15INK4b, p18INK4c, p19INK4d) are inhibitors of CDK4 (hence their name INhibitors of CDK4), and of CDK6. The other family of CKIs, CIP/KIP proteins are capable of inhibiting all CDKs. Enforced expression of INK4 proteins can lead to G1 arrest by promoting redistribution of Cip/Kip proteins and blocking cyclin E-CDK2 activity. In cycling cells, there is a resassortment of Cip/Kip proteins between CDK4/5 and CDK2 as cells progress through G1. Their function, inhibiting CDK4/6, is to block progression of the cell cycle beyond the G1 restriction point. In addition, INK4 proteins play roles in cellular senescence, apoptosis and DNA repair.
Cyclin D is a member of the cyclin protein family that is involved in regulating cell cycle progression. The synthesis of cyclin D is initiated during G1 and drives the G1/S phase transition. Cyclin D protein is anywhere from 155 to 477 amino acids in length.
Cyclin-dependent kinase 2, also known as cell division protein kinase 2, or Cdk2, is an enzyme that in humans is encoded by the CDK2 gene. The protein encoded by this gene is a member of the cyclin-dependent kinase family of Ser/Thr protein kinases. This protein kinase is highly similar to the gene products of S. cerevisiae cdc28, and S. pombe cdc2, also known as Cdk1 in humans. It is a catalytic subunit of the cyclin-dependent kinase complex, whose activity is restricted to the G1-S phase of the cell cycle, where cells make proteins necessary for mitosis and replicate their DNA. This protein associates with and is regulated by the regulatory subunits of the complex including cyclin E or A. Cyclin E binds G1 phase Cdk2, which is required for the transition from G1 to S phase while binding with Cyclin A is required to progress through the S phase. Its activity is also regulated by phosphorylation. Multiple alternatively spliced variants and multiple transcription initiation sites of this gene have been reported. The role of this protein in G1-S transition has been recently questioned as cells lacking Cdk2 are reported to have no problem during this transition.
Cyclin-dependent kinase 4 also known as cell division protein kinase 4 is an enzyme that in humans is encoded by the CDK4 gene. CDK4 is a member of the cyclin-dependent kinase family.
Cell division protein kinase 6 (CDK6) is an enzyme encoded by the CDK6 gene. It is regulated by cyclins, more specifically by Cyclin D proteins and Cyclin-dependent kinase inhibitor proteins. The protein encoded by this gene is a member of the cyclin-dependent kinase, (CDK) family, which includes CDK4. CDK family members are highly similar to the gene products of Saccharomyces cerevisiae cdc28, and Schizosaccharomyces pombe cdc2, and are known to be important regulators of cell cycle progression in the point of regulation named R or restriction point.
A cyclin-dependent kinase inhibitor protein(also known as CKIs, CDIs, or CDKIs) is a protein that inhibits the enzyme cyclin-dependent kinase (CDK) and Cyclin activity by stopping the cell cycle if there are unfavorable conditions, therefore, acting as tumor suppressors. Cell cycle progression is stopped by Cyclin-dependent kinase inhibitor protein at the G1 phase. CKIs are vital proteins within the control system that point out whether the processes of DNA synthesis, mitosis, and cytokines control one another. When a malfunction hinders the successful completion of DNA synthesis in the G1 phase, it triggers a signal that delays or halts the progression to the S phase. Cyclin-dependent kinase inhibitor proteins are essential in the regulation of the cell cycle. If cell mutations surpass the cell cycle checkpoints during cell cycle regulation, it can result in various types of cancer.
Cyclin D1 is a protein that in humans is encoded by the CCND1 gene.
Cyclin-dependent kinase inhibitor 1B (p27Kip1) is an enzyme inhibitor that in humans is encoded by the CDKN1B gene. It encodes a protein which belongs to the Cip/Kip family of cyclin dependent kinase (Cdk) inhibitor proteins. The encoded protein binds to and prevents the activation of cyclin E-CDK2 or cyclin D-CDK4 complexes, and thus controls the cell cycle progression at G1. It is often referred to as a cell cycle inhibitor protein because its major function is to stop or slow down the cell division cycle.
G1/S-specific cyclin-D3 is a protein that in humans is encoded by the CCND3 gene.
Cyclin-dependent kinase 7, or cell division protein kinase 7, is an enzyme that in humans is encoded by the CDK7 gene.
G1/S-specific cyclin-D2 is a protein that in humans is encoded by the CCND2 gene.
Cyclin-A2 is a protein that in humans is encoded by the CCNA2 gene. It is one of the two types of cyclin A: cyclin A1 is expressed during meiosis and embryogenesis while cyclin A2 is expressed in the mitotic division of somatic cells.
Cyclin-dependent kinase 4 inhibitor B also known as multiple tumor suppressor 2 (MTS-2) or p15INK4b is a protein that is encoded by the CDKN2B gene in humans.
Cyclin-dependent kinase 4 inhibitor D is an enzyme that in humans is encoded by the CDKN2D gene.
Cell division protein kinase 3 is an enzyme that in humans is encoded by the CDK3 gene.
Cyclin-dependent kinase inhibitor 3 is an enzyme that in humans is encoded by the CDKN3 gene.
Cell division protein kinase 10 is an enzyme that in humans is encoded by the CDK10 gene.
The CIP/KIP family is one of two families of mammalian cyclin dependent kinase (CDK) inhibitors (CKIs) involved in regulating the cell cycle. The CIP/KIP family is made up of three proteins: p21cip1/waf1, P27kip1, p57kip2 These proteins share sequence homology at the N-terminal domain which allows them to bind to both the cyclin and CDK. Their activity primarily involves the binding and inhibition of G1/S- and S-Cdks; however, they have also been shown to play an important role in activating the G1-CDKs CDK4 and CDK6. In addition, more recent work has shown that CIP/KIP family members have a number of CDK-independent roles involving regulation of transcription, apoptosis, and the cytoskeleton.