Analysis of StAR RNA Splicing and Lipid Droplets Composition in MA10 Cells Under Different Stimuli

Abstract

Steroidogenic acute regulatory protein (StAR) is a transport protein which plays a key role in steroidogenesis. Different pathways can activate StAR transcription. cAMP activates PKA which phosphorylates CREB. PKA also inhibits SIK1 which allows CRTC2 to bind to p-CREB and activate transcription. Differently, HG9 inhibits SIK forms which activate CRTC2 and allow it to bind to non-phosphorylated CREB which promote transcription. In this project, we are exploring how StAR post-transcription, especially splicing, is regulated under different media conditions and stimuli, and how the composition of lipid droplets changes with different stimuli over time. We found that the lagging is prolonged with HG9 stimulation compared to Br-cAMP stimulation and the increase of lipid droplets are much more substantive with high concentration of Br-cAMP.