Analyzing the Importance of Phosphorylation and Ubiquitination of Amino Acids in the Enhancer of Rudimentary Protein, ERH

Abstract

The enhancer of rudimentary gene, e(r), has been found to posses certain amino acids with the potential for phosphorylation or ubiquitination. All of these amino acids are highly conserved among species. It is possible that any of these sites might play a role in Enhancer of Rudimenary Homolog protein, ERH, activation by their respective modifications. This possibility has been analyzed through the creation of transgenes with codon changes at the identified sites intended to either prevent or mimic phosphorylation or ubiquitination. Upon insertion of the e(r) transgenes into the Drosophila melanogaster genome, they have been crossed with two lethal and one low viability stock of flies. The location of the e(r) gene on the X chromosome allows basic phenotypic observations based on eye color to reveal whether any mutations exhibit wild-type ratios of males to females. It has been determined that the phosphorylation of Y19, Y22, S47, and Y92 are not necessary in the activation of ERH. Likewise, the prevention of ubiquitination at K41 and K90 does not effect protein function. A double amino acid change at T18 and S24 in the same transgene has resulted in low viability when compared to the wild-type, suggesting a decreased amount of ERH activity as a result of this mutation in regards to the Notch signaling pathway.