LIFESCI 4 Lecture Notes - Lecture 19: Southern Blot, Northern Blot, Western Blot
LIFESCI 4 - Lecture 19 - Molecular Techniques and Gene Structure
Midterm 2 Question 8 Review:
The wild type (Hr+) of hypothetical phage T15 can only grow on E.coli B whereas the mutant
(Hr-) phage T15 can grow on both E.coli B and E.coli K strains. Ou want to determine the
recombination frequency between two hr mutations. The E.coli B strain is coinfected (at high
m.o.) with the following two mutant phage stocks.
(hr1- hr2-) X (hr1+ hr2+)
When the progeny is titered it is determined that 2.0 x 10^9 pfu/mL of the progeny phage stock
can grow on E.coli B but only 1.1 x 10^9 pfu/mL can grow on
Wt: B
Hr-: B and K
Hr1+ Hr2+ (parental) → grow on B only
Hr1- Hr2- (parental) → grow on B and K
Hr1+ Hr2- (recombinant) → grow on B and K
Hr1- Hr2+ (recombinant) → grow on B and K
B - K = # of 1 parental (Hr1+ Hr2+)
2 (B - K) = # of total parental (Hr1+ Hr2+) and (Hr1- Hr2-)
- To get # recombinants (which is equal to # of K), subtract [# of total parental]
from total number that grows on B (since everything grows on B, B = # total)
-F R= # total
# recombinants = B
B − 2(B−K)
Eukaryotic Gene Structure
- Genomic DNA → introns
- cDNA → coding sequence
- Polypeptide sequence
Clicker 1: Eukaryotic Gene Structure
- Southern Blot is for DNA
- Northern Blot is for RNA
- Western Blot is for protein
- Answer: D
- Nonsense mutation = premature stop codon → look at the stop codon
- The protein peptide will be shorter (D is the shortest one)
- Should not see difference in southern and northern blot
- Answer: E
Document Summary
Lifesci 4 - lecture 19 - molecular techniques and gene structure. The wild type (hr+) of hypothetical phage t15 can only grow on e. coli b whereas the mutant (hr-) phage t15 can grow on both e. coli b and e. coli k strains. Ou want to determine the recombination frequency between two hr mutations. The e. coli b strain is coinfected (at high m. o. ) with the following two mutant phage stocks. (hr1- hr2-) x (hr1+ hr2+) When the progeny is titered it is determined that 2. 0 x 10^9 pfu/ml of the progeny phage stock can grow on e. coli b but only 1. 1 x 10^9 pfu/ml can grow on. Hr1+ hr2+ (parental) grow on b only. Hr1- hr2- (parental) grow on b and k. Hr1+ hr2- (recombinant) grow on b and k. Hr1- hr2+ (recombinant) grow on b and k. B - k = # of 1 parental (hr1+ hr2+) 2 (b - k) = # of total parental (hr1+ hr2+) and (hr1- hr2-)
