Date of Award
Master of Science
Dr. Anthony Percival-Smith
The Drosophila HOX transcription factor, Sex Combs Reduced (SCR), is required for determining labial and the first thoracic segmental identity. A Protein Phosphatase 2A holoenzyme assembled with the PP2A-B' regulatory subunit has been proposed to specifically interact with and dephosphorylate SCR homeodomain activating SCR protein activity. To test this hypothesis, a null mutation was created in the PP2A-B' gene, PP2A- B'a, using Flip mediated site-specific recombination. The number of sex comb bristles, salivary gland nuclei and pseudotracheal rows are SCR-dependent and were counted as a measure of SCR activity in vivo. Adults and larvae homozygous for PP2A-B'a showed no decrease in SCR activity. In addition no evidence of functional redundancy of PP2A-B' with other regulatory subunits, Twins (TWS) and Widerborst (WDB) for dephosphorylation and activation of SCR activity was observed suggesting that PP2A has
no role in activation of SCR activity.
Moazzen, Hoda, "A regulatory subunit o f Protein Phosphatase 2A, PP2A-B', is dispensable for activation of Sex Comb Reduced activity in Drosophila melanogaster" (2009). Digitized Theses. 3768.