HO-22 - The cell division cycle and cancer genetics Cell...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
P -PO 3 2- = P Rb Rb E2F CDK (inactive) CyclinD Cyclin-CDK complex Substrate BIO 320 Reading: Ch 19. Lecture 22 Also review Ch 4.2 Question bank D-III text problems:19.1-4, 10-13, 19-27 The cell division cycle and cancer genetics Cyclins and cyclin-dependent kinases ( CDK s) are the key parts of the biochemical "clockwork" that drives the cell cycle Checkpoints are stages where cells arrest if not ready to complete the next stage. Dividing cells proceed through 4 distinct stages G1 S G2 M DNA replication; chromatid formation Mitosis and cell division Growth before DNA synthesis Preparation for division G0 Non-dividing state When bound to a cyclin, a CDK is activated and can phosphorylate other cell proteins to activate or inactivate them. Different cyclins appear (by regulated gene expression) and disappear (by protein degradation) at different stages of the cell cycle. Cell growth and division requires coordination and ordering of many complex processes: cell growth, DNA replication, nuclear disassem- bly, mitotic spindle construction, and chromosome segregation and cytokinesis. Genetic screens for conditional mutants of yeast identified many parts of the cell cycle machinery. At permissive (low) temperatures, the mutant protein is functional; mutant cells can proceed through the cell cycle Temperature-sensitive mutations make a protein unstable or non-functional at high temperatures. At restrictive (high) temperatures, the protein loses its function;
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 06/03/2008 for the course BIO 320 taught by Professor N/a during the Spring '08 term at SUNY Stony Brook.

Page1 / 2

HO-22 - The cell division cycle and cancer genetics Cell...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online