Question

4. Examine the figure below. What would be the effect on transcription if a mutation occurred in the gene that encodes GAL3, so that no functional GAL was produced? GAL4 UASC GAL80 In the absence of galactose, GAL80 blocks GAL4 from activating transcription TATA Basal transcription apparatus Galactose GAL3 GAL80 GAL3 2 When galactose is present, it binds to GAL3 and brings about a change in the Galactose conformation of GAL80. GAL80 no longer binds to GAL4. GAL4 TATA 3 GAL4 can now interact with the basal transcription apparatus and stimulate transcription.

Answer 1

No transcription of gene as provided figure When galactose i's poresent and it bind ito GAL3 it dead to change in conformation of GAL 80 then GALBO is no longen bind to GAL ¢ but When Ga13 is absent it will not bound galactose, Further no conformation GA180. GALSO remain to Change in the

ING bound to the interact with Str. GAL4 cannot transcriptional appratus No transcuiftion of gene.