Domain

K cyclin, C-terminal (IPR015164)

Short name: K-cyclin_C

Domain relationships

None.

Description

Cyclins are eukaryotic proteins that play an active role in controlling nuclear cell division cycles [PMID: 12910258], and regulate cyclin dependent kinases (CDKs). Cyclins, together with the p34 (cdc2) or cdk2 kinases, form the Maturation Promoting Factor (MPF). There are two main groups of cyclins, G1/S cyclins, which are essential for the control of the cell cycle at the G1/S (start) transition, and G2/M cyclins, which are essential for the control of the cell cycle at the G2/M (mitosis) transition. G2/M cyclins accumulate steadily during G2 and are abruptly destroyed as cells exit from mitosis (at the end of the M-phase). In most species, there are multiple forms of G1 and G2 cyclins. For example, in vertebrates, there are two G2 cyclins, A and B, and at least three G1 cyclins, C, D, and E.

Cyclin homologues have been found in various viruses, including Saimiriine herpesvirus 2 (Herpesvirus saimiri) and Human herpesvirus 8 (HHV-8) (Kaposi's sarcoma-associated herpesvirus). These viral homologues differ from their cellular counterparts in that the viral proteins have gained new functions and eliminated others to harness the cell and benefit the virus [PMID: 11056549].

This domain adopts a secondary structure consisting of a five alpha-helix cyclin fold. Interaction with cyclin dependent kinases (CDKs) at a PSTAIRE sequence motif within the catalytic cleft of CDK results in the regulation of CDK activity [PMID: 11124804].

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.
Pfam