KDC shows Divergent evolution, in which the genes for an enzyme with one substrate specificity give rise, during evolution, to closely related enzymes with different substrate specificities but the same enzymatic mechanism.

TLS Online TPP Program

#Id: 8618

#XL - T Zoology

Cdc25 phosphatase Activates CDKs in fission yeast

TLS Online TPP Program

#Id: 8619

#XL - T Zoology

INK4s

bind to CDK4 and CDK6 monomers, blocking their interaction with cyclin D

TLS Online TPP Program

#Id: 8620

#XL - T Zoology

A second class of CKIs found in metazoan cells is the Cip/Kip family of CKIs, consists of three proteins—p21CIP, p27KIP1, and p57KIP2. 

TLS Online TPP Program

#Id: 8621

#XL - T Zoology

The Cip/Kip family members bind to cyclin-bound CDKs and block the activity of cyclin D-, E-, A-, and B-containing complexes.

TLS Online TPP Program

#Id: 8622

#XL - T Zoology

Cyclins are degraded through the action of two different E3-ligases:

1. SCF (Skp1, Cullin, and F-box proteins) 

2. APC/C or cyclosome

TLS Online TPP Program

#Id: 8623

#XL - T Zoology

SCF and APC/C are multisubunit ubiquitin-protein ligases that belong to the RING finger family of ubiquitin-protein ligases.