BIOL 467 Lecture Notes - Lecture 8: Cyclin B1, Cyclin B, Cyclin-Dependent Kinase 1
Document Summary
In most animal cells you have cyclin a persisting from s phase partnering with cdk1. Cyclin b is synthesized closed to beginning of mitosis, and will then partners with cdk1 and important in taking over for the function of. This m phase specific cdk-cyclin complex(s) will activate the apc. Mitotic cdk-cyclin complexes trigger m phase: also activates apc cdc20 to destroy securing for sister chromatid separation and mitotic cyclins for mitotic exit (anaphase transition) (cid:862)a(cid:374)aphase pro(cid:373)oti(cid:374)g (cid:272)o(cid:373)ple(cid:454)(cid:863) (cid:373)ediati(cid:374)g tra(cid:374)sitio(cid:374) metaphase to anaphase. It(cid:859)s a e3 ligase mediate the attachment of poly- ubiquitin (cyclin e and a are the substrates) Cdc20 subunit targets the apc to cyclin b and cyclin a for their degradation. Target called securin crucial target cause securing when you remove it you allow for the physical separation of sister chromatids. Cdc20 gets replaced by cdh1 around end of mitosis any remaining cyclins are completely degraded. Most somatic cells with use both cyclin a and b.
