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Krupple and Giant in Drosophila

Kruppel and giant are 2 gap genes in drosophila for which the maternal effect gene bicoid serves as a transcriptional activator. Bicoid protein is present in an concentration gradient in the drosophila embryo, with the highest levels at the anterior end and progressively lower levels as one moves toward the posterior pole.

a) In general terms , what phenotype is expected of a mutation producing non-functional kruppel protein?

B) The expression domain of giant is anterior to that of kruppel with little overlap between the two. List 2 general types of gene regulatory mechanisms that contribute to these differences in expression pattern between giant and krupel.

c) hedgehog is an example of a segment polarity gene in drosophila. Would one expect any alterations of kruppel expression in embryos mutant for hedgehog? Why or why not?

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To start everything and anything you want to know about drosophila can be found here This is a comprehensive site with gene expression profiles and much, much more.

a) Krupple and giant are expressed in alternative stripes. They are known as gap genes because if one is deleted the expression of the other is expanded (they fill in the gap) and you lose the identity encoded by the gene. Krupple is responsible for anterior specification of each segment (if you need to know more about the anatomy of the fruit fly visite FlyBase). ...

Solution Summary

Answers to direct questions regarding krupple and the relation between gap genes and segment polarity genes.