Bio151 Sp13 Exam 3 answer key

A or b5 make a gof mutation in cap and add iptg and

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: on in the LacZ gene and add IPTG - A LOF in LacZ would not have an effect on txn – IPTG would give strong induction in both wt and mutant. B3. Make a LOF mutation in the LacI repressor and add lactose – In wt cells, repressor would not be bound so you’d get some txn and in these mutant cells repressor wouldn’t be bound as well – so in theory you’d get similar amounts of txn. B4. Mutate the enzyme (assume LOF) that makes cAMP and add glucose – in either situation there’s no lactose so repressor is bound so little to no txn. A or B5. Make a GOF mutation in CAP and add IPTG and glucose – in wt cells you’d see low to medium amounts of transcription because repressor not bound (because IPTG is there) but CAP isn’t bound as well (because glucose is there). In the mutant, you have no repressor bound but you DO have CAP bound because it can bind whether glucose around or not – because it has a GOF mutation. In theory, what I wrote in red would be true, but I let you guys in on a little secret in class (that IPTG gives strong induction whether glucose is present or not) so I’ll accept both answers. Questions 6- 10 You decide that you want to figure out a situation where you see constant transcription of the lac genes but you want the amount of transcription to be low (but not “off”). Which of these scenarios could work? A = Yes; B = No The basic idea behind...
View Full Document

This note was uploaded on 01/21/2014 for the course BIO 151 taught by Professor Randallphillis during the Fall '12 term at UMass (Amherst).

Ask a homework question - tutors are online