Question

You want to use immunofluorescence to examine the intracellular location of Protein X with various deletions in the coding region.

A) Based upon the wild type results presented below, indicate the expected location for the various mutants.

Protein X variant	Location of Protein X
wild type	ER
signal sequence deleted
KDEL sequence deleted

B) You have cells which are mutant in specific genes whose products are part of the

secretory pathway (sec genes). In each case, the protein encoded by the mutant gene is

completely nonfunctional and there is no wild type copy. You transfect the gene encoding

wild type Protein X from part A into the sec mutant cells. Indicate the expected location for

the Protein X in these sec mutants. Be as specific as possible.

Mutant Secretory Pathway Gene	Location of Protein X
mannose -6P receptor
ERD2
SRP
SRP-R

Answer 1