Activation of the IFN- globin promoter is an example of a histone code. Of the steps given, which is the third in this process?
A. The TATA box in the promoter is exposed.
B. Complexes containing Gcn5 bind to the promoter and acetylate nearby nucleosomes.
C. A chromatin remodeling complex such as SW1/SNF binds to and moves the nucleosome.
D. Initiation of transcription occurs.
E. A protein kinase binds to the Gcn5 complex and phosphorylates nearby nucleosomes.
Small guide RNAs (gRNA) of the editosome complex:
A. are complementary to a target sequence in the pre-edited RNA.
B. are only found in the nucleus.
C. acquire sequence differences copied from pre-mRNA.
D. typically contain a 3' terminal oligo(U) extension.
Treatment of eukaryotic cells with bacterial polypeptide actinomycin D will cause:
A. interference with the movement of tRNAs during polypeptide elongation on the ribosome.
B. blockage of splicing as mediated by snURP2.
C. no change; bacterial proteins will have no impact on the function of eukaryotic cells.
D. interference with transcript elongation by RNA polymerase II.
Insertions and deletions of three base pairs:
A. change one codon and, therefore, only one amino acid in the protein sequence.
B. do not disrupt the reading frame so the protein ends up completely normal.
C. do not disrupt the reading frame so the protein will usually retain some degree of function.
D. cause frameshifts that will change the reading frame and, therefore, the sequence of the protein.
E. usually result in the expression of a truncated protein.
Two reasons for two selectable markers in a YAC vector are:
A. to insure the EcoRI digest is complete.
B. to insure the desired recombinant construct has telomeres on both ends.
C. to contribute to the centromere structure.
D. to increase transformation efficiency.
E. to eliminate the possibility of screening unstable recombinants.
Quick Reply
