Lecture 9: Mutagenesis Flashcards
What is mutagenesis?
Production of genetic mutations.
Why is mutagenesis useful?
It is an informative approach to examining gene behavior/functions by creating a causal link between particular gene interruptions and observed phenotypic changes.
It is also one of the most efficient tools used for the identification of key regulatory genes (cell cycle) and molecular mechanisms.
What is a conditional mutagenesis screen?
An experimental technique used to identify and select individuals who posses a phenotype of interest in a mutagenised population.
It can be used to find the role and function of genes in the cell cycle.
+ Map each of the steps and key checkpoints in the cell cycle.
How do you screen for temperature sensitive mutants?
Temperature sensitive mutants are ‘conditional’.
At the restrictive temperature mutations in genes required for progression from one phase to the next cause yeast cells to arrest at the specific point in the cell cycle.
How do you distinguish cdc mutants from mutations in other essential genes?
CDC mutants arrest at a specific point in the cell cycle phase.
What is plasmid rescue?
Technique for recovering bacterial plasmids from transgenic eukaryotic genomic DNA.
How is plasmid rescue performed to identify human cell cycle genes?
1) Grown cdc2- mutants at permissive temperature.
2) Transform mutant cells with plasmid library of human genes (gene X, gene Y, and gene Z . . .).
3) Shift transformed cells to the restrictive temperature.
Only cells transformed with the wild-type copy equivalent to the mutated gene will grow.
