Electronic Thesis and Dissertation Repository


Master of Science




Caroline Schild-Poulter


RanBPM is an evolutionarily conserved multi-domain protein that has been implicated in the regulation of several cellular process, including protein stability, cell migration, gene transcription, and apoptosis. RanBPM is identified as a key member of the CTLH complex, an orthologous complex to a yeast E3 ubiquitin ligase complex, the exact function of which remains unknown. Previously, our laboratory identified RanBPM as an inhibitor of the ERK1/2 pathway through the modulation of C-RAF protein levels. This study shows that RanBPM-mediated degradation of C-RAF occurs through the proteasome and the entire CRA domain of RanBPM is necessary for direct interaction with C-RAF and for effective downregulation of C-RAF in human cells. Finally, the CTLH complex member RMND5A regulates endogenous C-RAF protein levels further implicating the CTLH complex in RanBPM-mediated regulation of C-RAF stability. This study provides further insight into the function of RanBPM and the CTLH complex, and their regulation of C-RAF.