MGA Antibody / MAX gene associated protein

Mga is a DNA-binding protein that activates the expression of several important virulence genes in Streptococcus pyogenes (group A Streptococcus, GAS) in response to changing environmental conditions. It had been found that the mouse transcription factor Max interacted with Mga. Coimmunoprecipitation analysis confirmed that Max and Mga interacted in transfected HEK293 cells. EMSA revealed that Mga required Max for binding to the E-box sequence CACGTG. The isolated T-box of Mga bound the brachyury T-box-binding site in the absence of Max. Mga repressed transcription of a reporter driven from a T-box-binding site, but coexpression of Mga with Max caused transcriptional activation from the T-box-binding site. Expression of Mga with Max, but not Mga alone, activated transcription from a reporter containing the E-box site.