UC Davis

Seasonal changes in temperature and photoperiod necessitate a wide range of organisms to adjust their physiology and behavior to survive an unfavorable environment. In insects, one of the main seasonal adaptations is reproductive dormancy. It is the complete arrest of reproductive output and typically occurs in winter. In a previous study, our lab found that EYES ABSENT (EYA) was involved in promoting reproductive dormancy, but the molecular mechanism underlying its role in seasonal regulation is poorly understood. Because EYA has been shown to regulate Protein Phosphatase 2A (PP2A) through binding to the B55a/TWINS (TWS) subunit, we proposed a coincidence model that suggests the interaction between EYA and TWS may promote winter physiology by dephosphorylating substrates in the insulin signaling pathway. The insulin signaling pathway is known to promote summer physiology when activated by phosphorylation. Although previous reports showed that EYA protein cycles over the 24 hours (h) with peak protein expression shifting from day to nighttime in laboratory simulated summer and winter conditions respectively, I observed that summer and winter EYA expression in a fly strain expressing a TWS-GFP fusion protein vs in a wild type strain were inconsistent. Because GFP tags can alter protein function and protein-protein interactions, I constructed a TWS antigen to generate a TWS polyclonal antibody for detecting endogenous levels of TWS protein, which will allow future experiments to assay TWS expression and function without a protein tag and enable investigation of the role of TWS in seasonal physiology.