Biology 2581B Study Guide - Quiz Guide: Repressor Lexa, Ura3, Zinc Finger

• School: Western University
• Department: Biology
• Course: Biology 2581B
• Professor: Susanne Kohalmi

Document Summary

Proposals: reduce activation by gal4, directly repress structural genes, tup1, lexa bind lexa binding dna sequences, recruitment of hdacs acetyl removal less accessible chromatin of, mutating hdacs - compromise tup repressive function require. Interact with mediator / transcriptional machinery mutation of mediator can reduce tup effect @ some genes this as co-effector promoter. In absence, gal4 bound to gal80 bound to uas but can"t recruit transcription complex. Detected by gal3 (galactose sensor) bind gal80 (upon galactose and atp binding) frees. If at remote binding sites, need looping to facilitate. Can be demonstrated with telomeric placement of marker and activator: gal4 activated. Ura3 when at telomere, co-operative binding possible due to inherent looping (binding site close to promoter of gene) Gal3 in presence of galactose, may bind gal80 prevent inhibition of gal4. Reverse: normally shuttles, when galactose gal3 in nucleus long enough to prevent gal80. Gal11 co-activator form part of mediator complex recruitment of basal transcriptional.