Ssn6-Tup1 global transcriptional co-repressor: Role of the N-terminal glutamine-rich region of Ssn6.

The Ssn6-Tup1 complex is a general transcriptional co-repressor formed by the interaction of Ssn6, a tetratricopeptide repeat (TPR) protein, with the Tup1 repressor. We have previously shown that the N-terminal domain of Ssn6 comprising TPRs 1 to 3 is necessary and sufficient for this interaction and that TPR1 plays critical role. In a subsequent study, we provided evidence that in the absence of Tup1, TPR1 is susceptible to proteolysis and that conformational change(s) accompany the Ssn6-Tup1 complex formation.

SRPK1 and Akt Protein Kinases Phosphorylate the RS Domain of Lamin B Receptor with Distinct Specificity: A Combined Biochemical and In Silico Approach.

Activated Akt has been previously implicated in acting on RS domain-containing proteins. However, it has been questioned whether its action is direct or it is mediated by co-existing SR kinase activity. To address this issue we studied in detail the phosphorylation of Lamin B Receptor (LBR) by Akt.