title: Histone methyltransferase SETD2 coordinates FACT recruitment with nucleosome dynamics during transcription.
abstract: Histone H3 of nucleosomes positioned on active genes is trimethylated at Lys36 (H3K36me3) by the SETD2 (also termed KMT3A/SET2 or HYPB) methyltransferase. Previous studies in yeast indicated that H3K36me3 prevents spurious intragenic transcription initiation through recruitment of a histone deacetylase complex, a mechanism that is not conserved in mammals. Here, we report that downregulation of SETD2 in human cells leads to intragenic transcription initiation in at least 11% of active genes. Reduction of SETD2 prevents normal loading of the FACT (FAcilitates Chromatin Transcription) complex subunits SPT16 and SSRP1, and decreases nucleosome occupancy in active genes. Moreover, co-immunoprecipitation experiments suggest that SPT16 is recruited to active chromatin templates, which contain H3K36me3-modified nucleosomes. Our results further show that within minutes after transcriptional activation, there is a SETD2-dependent reduction in gene body occupancy of histone H2B, but not of histone H3, suggesting that SETD2 coordinates FACT-mediated exchange of histone H2B during transcription-coupled nucleosome displacement. After inhibition of transcription, we observe a SETD2-dependent recruitment of FACT and increased histone H2B occupancy. These data suggest that SETD2 activity modulates FACT recruitment and nucleosome dynamics, thereby repressing cryptic transcription initiation.
authors: Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisboa, Portugal.
authors: Sílvia
authors: S
authors: Carvalho
authors: Ana Cláudia
authors: AC
authors: Raposo
authors: Filipa Batalha
authors: FB
authors: Martins
authors: Ana Rita
authors: AR
authors: Grosso
authors: Sreerama Chaitanya
authors: SC
authors: Sridhara
authors: José
authors: J
authors: Rino
authors: Maria
authors: M
authors: Carmo-Fonseca
authors: Sérgio Fernandes
authors: SF
authors: de Almeida
mesh_terms: D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism*; D055785:Gene Knockdown Techniques; D057809:HEK293 Cells; D006367:HeLa Cells; D006609:High Mobility Group Proteins / Q000378:metabolism*; D011495:Histone-Lysine N-Methyltransferase / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D006801:Humans; D007700:Kinetics; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D009707:Nucleosomes / Q000378:metabolism*; D011485:Protein Binding; D012319:RNA Polymerase II / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics; D051742:Transcription Factor CHOP / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D024363:Transcription Initiation Site; D061785:Transcription Initiation, Genetic; D014158:Transcription, Genetic; D015533:Transcriptional Activation; D035602:Transcriptional Elongation Factors / Q000378:metabolism*; D059467:Transcriptome
chemical_list: D018797:Cell Cycle Proteins; C497249:DDIT3 protein, human; D004268:DNA-Binding Proteins; C485932:HERPUD1 protein, human; D006609:High Mobility Group Proteins; D008565:Membrane Proteins; D009707:Nucleosomes; D034741:RNA, Small Interfering; C073537:SSRP1 protein, human; C489489:SUPT16H protein, human; D014157:Transcription Factors; D035602:Transcriptional Elongation Factors; D051742:Transcription Factor CHOP; D011495:Histone-Lysine N-Methyltransferase; C521636:SETD2 protein, human; D012319:RNA Polymerase II