Question

If you wanted to find a protein that binds RNA to perhaps regulate RNA degradation or translation, you could test protein binding this RNA by __. (application question)

A	Gel shift
B	Southern
C	Northern
D	Western

If one performed co-immunoprecipitation where antibodies were used to precipitate 1) TFIID (20 kD), 2) TFII B (40 kD) or 3) TFII H (50 kD) and then a western was performed with the TFII B antibody, which lanes (1,2, 3 or combination below) would we see the 40 kD size protein?

Use scratch paper--highly suggested

A	1 and 3
B	1 and 2
C	2 and 3
D	2 only

you have a pre-mRNA with exon 1 of 300 bp, exon 2 of 400 bp and intron of 250 bp. For the pre-mRNA, which of the following sizes below represents the lariat after the first trans-esterification? answers are in base pairs.

A	700
B	650
C	950
D	550

Which 2 proteins can bind the lac operon concurrently? Assume it's "on".

A	activator and repressor
B	repressor and RNA polymerase
C	cap protein and repressor
D	cap protein and RNA polymerase

Answer 1

1. If you wanted to find a protein that binds RNA to perhaps regulate RNA degradation or translation, you could test protein binding this RNA by __.

Answer: Gel shift. Gel shift is a technique for monitoring the mobility shift in the electrophoresis in DNA-protein complex or RNA- protein complex.

2. If one performed co-immunoprecipitation where antibodies were used to precipitate 1) TFIID (20 kD), 2) TFII B (40 kD) or 3) TFII H (50 kD) and then a western was performed with the TFII B antibody, which lanes (1,2, 3 or combination below) would we see the 40 kD size protein?

Answer: Lane 1 and 2. TFIIB interacts with TFIID. so in lane 1, TFIID will pull TFIIB and can be observed when western was performed with the TFII B antibody. In the lane 2, TFIIB is precipitated in the first step and can be observed after the western. However, TFIID does not bind to TFIIB so TFIIB will not be pull with antibody specific for TFIID and cannot be observed in the lane 3.

3.