Hh and Wnt Signalling

Question 1

what defined both Wingless/Wnt and hedgehog gene at first

Answer 1

defined as mutations that showed defects in segmentation in drosophila

Question 2

Loss of the Hedgehog gene leads to

Answer 2

segment polarity phenotype

• In each segment the “naked” part is lost creating an embryo full with denticles

Question 3

loss of wingless causes:

Answer 3

loss of wingless will also lead to the loss of hedgehog expression and therefore gives a very similar phenotype

Question 4

what helps Hh to be targeted to secretory pathway

Answer 4

Hedgehog genes are translated with an N-terminal signal sequence that targets them to the secretory pathway

Question 5

What is the importance of the Ct

Answer 5

• The signal sequence is removed and then the protein undergoes an autoproteolytic cleavage catalysed by the C-terminal part of the protein
This c terminal part has no other role than promoting this cleavage