1. Parkin is an E3 ubiquitin ligase. Which of the following is/are parkin substrates? a. aSp22 form of alpha-synuclein b.Pael-R c.Synphilin d. Cyclin E e. All of the above 2.a-synuclein can be found to migrate at 22 kDa while it's predicted molecular weight is 16 kDa.This is due to... a.proteolytic processing b.ubiquitination c.phosphorylation d.O-glycosylation e. N-glycosylation 3. What are the minimal components needed for an in vitro ubiquitin ligase assay to poly- ubiquitinate substrate? a.E1, E2, IP-parkin, substrate b.E1, E2, IP-parkin, parkin peptide, ubiquitin c. E1, E2, IP-parkin, ubiquitin d. E1, E2, IP-parkin.