Exam 2 Study Guide
1.) Eukaryotic RNA polymerases require transcription factors to bind to the correct
2.) Promoters vs. Enhancers: Promoters bind to general transcription factors and facilitate
basal transcription. Enhancers are bind-specific and require gene specific (chromatin
makes DNA loop) transcription factors that increase the rate of transcription, enhancer
sequence can go backwards or forwards and would still be recognized by the DNA.
3.) Define Chromatin Immunoprecipitation, immunofluorescence and mass spec
4.) siRNA inhibits gene expression by working against the activator
5.) Azacytadine increases gene expression in a gene regulated by methylation, because
methylation decreases gene expression via condensing chromatin
6.) The 23S rRNAis the catalyst of peptide bond formation
7.) microRNA’s regulate translation by targeting specific RNA’s (bind to specific sequences
of 3’ untranslated regions of target mRNA’s)
8.) Inhibiting eIF4E (binds to 5’ cap in RNA’s which regulates translation because translation
factors recognize the 5’ cap). The mRNA in question has an internal ribosomal entry site.
Inhibiting eif4e would have no effect. It would still be processed but just not by regulation
of eif4e because the mRNA in question has a specific entry site.
9.) Proteases are responsible for protein catabolism by hydrolysis of peptide bonds. First
option: lysosomal proteins (digests proteins) so yes. Second option: mitochondrial
proteins (responsible for packaging nuclear energy in cell) so no. Third option: nuclear
proteins (digestive and proteases are in nucleus) so yes. Fourth option: ribosomal
proteins (process RNA) so no.
10.) Located in phospholipid bilayer and it is option as glycoprotein if lipid modified.
11.) Ran is an transport regulating protein (GTP Binding ): siRNA would inhibit both
import and export
12.) ER signaling sequence is on the N terminus so if it is deleted then the signal will
go anywhere in the cell ( maybe degraded) but the ER
14.) Operon is the operator sequence that has promoter and structural genes. When
lack lactose, cannot bind to it so operon attaches to promoter site and inhibit
transcription. When is available the lactose binds to the allosteric site of the repressor.
15.) Half of histones from on