You are studying regulation of the yeast enzyme glutamine synthetase (GS), which is encoded by the GLN1 gene. You have isolated two mutants, designated gln2– and gln3–, that give decreased GS activity. Mating of either gln2– or gln3– haploids to wild type produces heterozygous diploids that show normal amounts of GS expression. When you cross either a gln2– or gln3– haploid to a gln1– strain the resulting diploids show normal expression of GS.              

From these experiments,  Classify  the  gln2– and gln3– mutations in terms of their basic genetic properties explaining the rationale behind your conclusions. Based on these properties make a proposal for the types of regulatory functions affected by the gln2– and gln3– mutations.

#Question id: 4410

#Unit 3. Fundamental Processes

A key component of the eukaryotic transcription machinery called TFIID includes a

#Question id: 4411

#Unit 3. Fundamental Processes

All of the following are associated with vertebrate promoters located in active chromatin EXCEPT

#Question id: 4412

#Unit 3. Fundamental Processes

TATA less promoters without Inr and DCE are expressed

#Question id: 4413

#Unit 3. Fundamental Processes

Which of the following is true about TFIID?

#Question id: 4414

#Unit 3. Fundamental Processes

The helicase of TFIIH hydrolyzes the β-γ bond of ATP to catalyze open complex formation at Pol II promoters. ATP hydrolysis is also required by a step subsequent to transcription initiation, most likely promoter clearance. Transcriptional activation by TFIIH was assayed on linear and circular templates either in the presence of ATP and GTP or the nonhydrolyzable nucleotide analogs AMP-PNP and GMP-PNP with RNA Polymerase I. The following results were obtained. Choose plausible explanation for these results. 

A. ATP is required under conditions where TFIIH is indispensable for initiation. These conditions include transcription from promoters containing a short stretch of mismatched base pairs surrounding the transcriptional start site as well as on negatively supercoiled templates.

B. As Pol I transcription on linear templates requires neither ATP hydrolysis nor protein phosphorylation

C. in contrast to Pol II, the topology of the template does not affect the requirement for TFIIH and neither the ATPase, helicase, nor protein kinase activity of TFIIH are required for Pol I transcription activation.

#Question id: 4415

#Unit 3. Fundamental Processes

PML nuclear bodies are also sites of post-translational modification of proteins through the addition of