A powerful approach to identifying genes of a developmental pathway is to screen for mutations that suppress or enhance the phenotype of interest. This approach was undertaken to elucidate the genetic pathway controlling C. elegans vulval development. . Part A

A lin-3 loss-of-function mutant with a vulva-less phenotype was mutagenized. Based on your knowledge of the genetic pathway, what types of mutations will suppress the vulva-less phenotype?

Check all that apply.

A. gain-of-function intracellular signal molecule (LET-60) activated by lin-3 mutants
B. loss-of-function intracellular signal molecule (LET-60) activated by lin-3 mutants
C. loss-of-function lin-3 receptor mutants
D. loss-of-function lin-3 mutants
E. gain-of-function lin-3 receptor mutants

Part B

In a complementary experiment, a gain-of-function let-23 mutant with a multi-vulva phenotype was also mutagenized. What types of mutations will suppress the multi-vulva phenotype?

Check all that apply.

A. gain-of-function intracellular signal molecule (LET-60) activated by lin-3 mutants
B. gain-of-function lin-3 receptor mutants
C. loss-of-function lin-3 receptor mutants
D. loss-of-function intracellular signal molecule (LET-60) activated by lin-3 mutants