Cyclin-dependent kinases regulatory subunit 1 is a protein

Protein

Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...

 that in humans is encoded by the CKS1B gene

Gene

A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...

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Function

The CKS1B protein binds to the catalytic subunit of the cyclin-dependent kinase

Cyclin-dependent kinase

thumb|350px|Schematic of the cell cycle. outer ring: I=[[Interphase]], M=[[Mitosis]]; inner ring: M=Mitosis; G1=[[G1 phase|Gap phase 1]]; S=[[S phase|Synthesis]]; G2=[[G2 phase|Gap phase 2]]...

s and is essential for their biological function. The CKS1B mRNA

Messenger RNA

Messenger RNA is a molecule of RNA encoding a chemical "blueprint" for a protein product. mRNA is transcribed from a DNA template, and carries coding information to the sites of protein synthesis: the ribosomes. Here, the nucleic acid polymer is translated into a polymer of amino acids: a protein...

 is found to be expressed in different patterns through the cell cycle in HeLa cells

HeLa

A HeLa cell is a cell type in an immortal cell line used in scientific research. It is the oldest and most commonly used human cell line. The line was derived from cervical cancer cells taken on February 8, 1951 from Henrietta Lacks, a patient who eventually died of her cancer on October 4, 1951...

, which reflects a specialized role for the encoded protein.

Clinical significance

Cks1-depleted breast cancer cells not only exhibit slowed G(1) progression, but also accumulate in G(2)-M due to blocked mitotic entry. Cdk1 expression, which is crucial for M phase entry, is drastically diminished by Cks1 depletion, and that restoration of cdk1 reduces G(2)-M accumulation in Cks1-depleted cells.

Interactions

CKS1B has been shown to interact

Protein-protein interaction

Protein–protein interactions occur when two or more proteins bind together, often to carry out their biological function. Many of the most important molecular processes in the cell such as DNA replication are carried out by large molecular machines that are built from a large number of protein...

 with SKP2

SKP2

S-phase kinase-associated protein 2 is an enzyme that in humans is encoded by the SKP2 gene.- Function :This gene encodes a member of the F-box protein family which is characterized by an approximately 40 amino acid motif, the F-box domain...

 and CDKN1B

CDKN1B

Cyclin-dependent kinase inhibitor 1B is an enzyme that in humans is encoded by the CDKN1B gene. It encodes a protein which belongs to the Cip/Kip family of cyclin dependent kinase inhibitor proteins. The encoded protein binds to and prevents the activation of cyclin E-CDK2 or cyclin D-CDK4...

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