Chemistry and Biochemistry Seminar: Michael Massiah
Characterizing the interactions of the B-box E3 ligase with E2 conjugating enzyme: Learning about protein ubiquitination.
Michael Massiah (George Washington University)
Dr. Massiah will present recent work on the B-box domain from the human MID1 protein. The B-box domain may represent a new member of the ubiquitin E3 ligase, with similar fold as the RING-type E3 ligase. However, it has weaker activity. Despite this, it is require for the targeting and polyubiquitination of protein phosphatase 2A (a molecular master switch), alpha4, and the fused kinase. To understand how the B-box domain functions, NMR and fluorescence spectroscopy were used to characterize its interaction with the E2 enzyme, UbcH5, and mutagenesis to identify structural features that are important for ligase activity, and to engineer a more active E3 ligase. He will also discuss interesting observation how RNA affect MID1 E3 ligase activity.