Suppose you isolate a mutation affecting development of the Drosophila embryo in

Question

Suppose you isolate a mutation affecting development of the Drosophila
embryo in which every other segment of the developing mutant larva is missing.

a. What “kind” of developmental gene is most likely mutated?

b. You have mapped the mutation to a region of the genome thatcontains four genes. Describe how, by examining the expressionpattern of these genes, you could determine which gene most likelycontained the causal mutation.

c. Assume that you have identified the candidate gene. If you examine itsexpression pattern in an embryo that is homozygous mutant for thegap gene Kruppel, would you expect to see a normal or disruptedpattern? Why?

Explanation / Answer

a. As per the given data, here, segment polarity genes are most likely mutated. These genes determine the boundaries, and anterior-posterior orientation of each segment.

b. The given data tells that the embryo is missing segments. This suggests that segment polarity genes are not properly synthesized. So, when we observe the expression pattern of the four genes, the mutant gene would have less or no mRNA produced.

c. Kruppel is a gap gene, so we would observe a disrupted pattern in the formation of body parts, and segments.

Related Questions

Navigate

• Browse (All)
• Browse S
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.