Cell Cycle I Flashcards
How was MPF discovered?
Fusing mitotic cell with G1 phase cell. Since MPF is a cytoplasmic factor, there was premature chromosome condensation in the chromosomes of G1 phase. This produces pulverized chromatin, which causes cell death. This also teaches us that order of cell cycle is important
What are the phases of the cell cycle and what happens in each?
- G0 is quiescent (can be activated to proceed)
- G1: gap1 and growth.
- S: DNA synthesis, genome replication.
- G2: gap2 and growth and preparation for mitosis.
- interphase= g1, s, g2
- M phase: chromosome segregation and cytokinesis.
How were cell cycle regulatory genes discovered? Which experimental conditions provided evidence?
Look at temperature sensitive mutants through shift from 23-36 degrees. Mutagenize culture of yeast cells, plate on agar at low density, replica plate and out at permissive temp (23), in which all cell cycle stages can be observed, and restrictive temp (36), which prevented cytokinesis. Can tell which stage of cell cycle yeast arrested in. CDC cell division cycle genes conserved in all eukaryotes.
