ANSWERS are on the next page!
1. Know the basic differences between pre mRNA and mature mRNA.
2. Know the general function of the following RNA molecules at the level of Table 9.1 in
the slides: Small nuclear RNAs (snRNA), Small nucleolar RNA (sno RNA), Short
interfering RNA (si RNA) and microRNA (mi RNA).
3. Be able to draw and/or describe the two ‘transesterification’ reactions (which I called a
nucleophilic attack) that result in the 5’-3’ splicing out of introns.
4. Know where the two sn RNAs, U1 and U2 bind to complete the splicing process.
5. Be able to explain the ‘current’ functions of the following molecules:
a. CBC (cap binding complex) - transcription factor for promoter location and
recruits P-Tef.
b. NPC (nuclear pore complex) - nucleoporin forms the channel and can be involved
in deleterious mutations.
c. PABPC1 (polyA binding protein cytosol 1) - Required for Poly A shortening.
d. Sky 1 - Degrades stress granules in yeast. Modulates apoptosis
6. Know the basic model for polyadenylation of pre mRNA (Fig 9-15). You should know
PAP functions and the fact that there is a conserved Poly A signal or binding site that will
direct PAP. Know there is a slow and fast phase and that binding of PABPN1 both starts
the fast phase and the termination of the polymerization of the poly A tail.
7. Know that differential splicing is a common way to express different proteins or isomers
in different tissues.
8. Know the general dynamics of mRNA transportation out of the nucleus. What is the
function of the NPC (nuclear pore complex)?
9. Where can degradation of mRNA molecules occur?
10. Where does the initial r RNA processing occur?