Schizosaccharomyces pombe displays a large transcriptional response common to several stress conditions, regulated primarily by the transcription factor Atf1. Atf1-dependent promoters contain especially broad nucleosome depleted regions (NDRs) prior to stress imposition. We show here that basal binding of Atf1 to these promoters competes with histones to create wider NDRs at stress genes. Moreover, deletion of atf1 results in nucleosome disorganization specifically at stress coding regions and derepresses antisense transcription. Our data indicate that the transcription factor binding to promoters acts as an effective barrier to fix the +1 nucleosome and phase downstream nucleosome arrays to prevent cryptic transcription.

Spanish Ministry of Science and Innovation [BFU2012-32045]; PLAN E and FEDER; Generalitat de Catalunya (Spain) [SGR2009-195 to E.H.]; ICREA Academia Awards (Generalitat de Catalunya) [to J.A. and E.H.]; Juan de la Cierva from the Spanish Ministry of Science and Innovation[toP.G.]. Funding for open access charge: Spanish Ministry of Science and Innovation [BFU2012-32045]; PLAN E and FEDER; Generalitat de Catalunya (Spain) [SGR2009-195 to E.H.]