BIOLOGY 2B03 Lecture Notes - Lecture 58: Recognition Sequence, Sic1, Microtubule
Document Summary
G1 phase: cell growing, gene expression, synthesis of new proteins, duplicaion of chromosomes. S phase: further duplicaion of chromosomes and dna synthesis. G0 phase: short period of inacivity before daughter cell re-enters cell cycle. Failure in precise regulaion of cell cycle can lead to cell death or over-proliferaion of cells. Once cell is difereniated, does not undergo cell division: balance between cell division and difereniaion is important: too much cell division = formaion of tumour. Too much difereniaion = body"s loss of the ability to regenerate and replace lost issues because less undifereniated cells. Mitosis regulated by two classes of proteins: e3 ligase complexes (regulated degradaion): target speciic proteins for degradaion in proteasome. In this way, cyclins degraded to turn of kinases or cell cycle inhibitors can be degraded when checkpoints passed. 4 major classes: g1 cyclin- cdk: leads to acivaion of s-cyclin-cdk. Apc-cdh1 at end of mitosis to signal compleion of m-phase.
