Question : You have developed an in vitro assay for both splicing and : 2134129
94) You have developed an in vitro assay for both splicing and polyadenylation. You generate in vitro radioactively labeled pre-mRNA substrates that either include a 5′ cap or lack the 5′ cap. You incubate these labeled pre-mRNA substrates with mammalian cell nuclear extract and run out the products on a sequencing gel. You then distinguish the products based on their relative size in the gel. You get the following results where the number of pluses is related to the relative amount of radioactivity found in that band on the gel:
Propose a hypothesis that explains these results.
95) You have discovered a minor class of rare introns that use a distinct splicing machinery involving snRNPs U110, U120, and U140. An experiment was performed to determine the order of assembly. A pre-mRNA was attached to agarose beads and incubated with purified splicing components. At time points from 0-20 minutes, RNA was extracted from the beads and analyzed by Northern blot with labeled probes specific for each RNA. In what order are the snRNPs assembled?