Histone methylation is a reversible modification regulated by the antagonistic functions of residue-specific histone methyltransferases and demethylases. Although methylation of histone H3 at lysines 4 and 36 is linked to transcription, the roles of histone demethylases in transcription regulation are not understood. Here we show that overexpression of either Jhd1 or Rph1, two JmjC-domain proteins, bypasses the requirement for the positive elongation factor gene BUR1. Biochemical analysis and chromatin immunoprecipitation experiments indicate that Rph1 functions as a specific demethylase for H3 K36me3 and K36me2, directly regulating Lys36 methylation in transcribed regions. Both Jhd1 and Rph1 are required for normal levels of RNA polymerase II cross-linking to genes. Taken together, these findings indicate that a general function of histone demethylases for H3 Lys36 is to promote transcription elongation by antagonizing repressive Lys36 methylation by Set2.
This work was supported by Grant GM46498 (to S. B.) from the National Institutes of Health. This work was also supported by a Korea Research Foundation Grant funded by the Korean Government (MOEHRD) (KRF-2006-214-C00065). The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked “advertisement” in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
