In a cactus null mutant in which cells will Dorsal protein b

In a cactus null mutant, in which cells will Dorsal protein be localized to the nucleus? Why? What is the resulting phenotype?

Solution

In cactus nullmutant the nuclear localization takes place in the Rel protein called Dorsal protein because

the Dorsal protein is usually phosphorylated by the ventral signal as it is associated with Cactus,and this Dorsal phosphorylation is very important for its nuclear import and without it the process cannot accomplish.

The resulting phenotype is Dorsal protein Null mutant.