Characterization of Endogenous SAS3 in C. neoformans via Co-Immunoprecipitation

The predicted amino acid sequence of Something About Silencing 3 (SAS3) gene in Cryptococcus neoformans suggests that it contains a putative Histone Acetyltransferase (HAT) domain. Its role as a response/transcriptional modulator is further implied by its upregulation that is associated with Cryptococcal meningitis. Thus, there is a possible etiological correlation between SAS3 activity and cryptococcosis infection. To date, it has been determined that recombinant SAS3 does not display HAT activity on recombinant histones in vitro. Current experimentation is seeking to ascertain its endogenous role. This may point to the idea that endogenous SAS3 requires post-translational modifications before it is active, or that it binds to other proteins to function. Co-Immunoprecipitation (Co-IP) is being utilized to ascertain whether SAS3 functions as part of protein complex. The team is employing two methodologies for Co-IP to determine the most efficient way of determining whether SAS3 associates with other proteins. Therefore, the development of current protocol leaves ample opportunity for characterization of SAS3 activity in the near future.