The Effect on Transcriptional Activity of Mutations that Alter Possible Phosphorylation Sites in Drosophila melanogaster Ultraspiracle (USP)

UNCG Author/Contributor (non-UNCG co-authors, if there are any, appear on document)
Katherine M. Clifton (Creator)
Institution
The University of North Carolina at Greensboro (UNCG )
Web Site: http://library.uncg.edu/
Advisor
Vincent Henrich

Abstract: During insect development, steroid hormones interact with two members of the nuclear receptor superfamily, ecdysone receptor (EcR) and Ultraspiracle (USP) to bring about cellular changes. To determine the functional properties of mutations of serine and threonine residues that are possible targets of phosphorylation by protein kinase C (PKC) in the gene that encodes the D. melanogaster USP, we developed a heterologous mammalian cell culture system. When tested with the three natural isoforms of D. melanogaster EcR, one of the five mutations, S112A in the DNA-binding domain of USP, reduced basal and induced transcriptional activity, by itself and in most combinations with other mutations. Treatment with a PKC inhibitor, chelerythrine chloride (CC), itself had no effect on the transcriptional activity with wild-type USP and with any of the combination of mutations suggesting that the difference in activity caused by S112A does not involve phosphorylation. These mutational studies create a foundation for future in vivo experiments.

Additional Information

Publication
Thesis
Language: English
Date: 2007
Keywords
Drosophila melanogaster, Genetics, Ecdysteroids, Insect hormones, Insects