Transcription activator WCC recruits deacetylase HDA3 to control transcription dynamics and bursting in <i>Neurospora</i>.

Abstract

RNA polymerase II initiates transcription either randomly or in bursts. We examined the light-dependent transcriptional activator White Collar Complex (WCC) of <i>Neurospora</i> to characterize the transcriptional dynamics of the strong <i>vivid</i> (<i>vvd</i>) promoter and the weaker <i>frequency</i> (<i>frq</i>) promoter. We show that WCC is not only an activator but also represses transcription by recruiting histone deacetylase 3 (HDA3). Our data suggest that bursts of <i>frq</i> transcription are governed by a long-lived refractory state established and maintained by WCC and HDA3 at the core promoter, whereas transcription of <i>vvd</i> is determined by WCC binding dynamics at an upstream activating sequence. Thus, in addition to stochastic binding of transcription factors, transcription factor-mediated repression may also influence transcriptional bursting.