Histone H2B Ubiquitylation Is Associated with Elongating RNA Polymerase II

ABSTRACT Rad6-mediated ubiquitylation of histone H2B at lysine 123 has been linked to transcriptional activation and the regulation of lysine methylation on histone H3. However, how Rad6 and H2B ubiquitylation contribute to the transcription and histone methylation processes is poorly understood. Here, we show that the Paf1 transcription elongation complex and the E3 ligase for Rad6, Bre1, mediate an association of Rad6 with the hyperphosphorylated (elongating) form of RNA polymerase II (Pol II). This association appears to be necessary for the transcriptional activities of Rad6, as deletion of various Paf1 complex members or Bre1 abolishes H2B ubiquitylation (ubH2B) and reduces the recruitment of Rad6 to the promoters and transcribed regions of active genes. Using the inducible GAL1 gene as a model, we find that the recruitment of Rad6 upon activation occurs rapidly and transiently across the gene and coincides precisely with the appearance of Pol II. Significantly, during GAL1 activation in an rtf1 deletion mutant, Rad6 accumulates at the promoter but is absent from the transcribed region. This fact suggests that Rad6 is recruited to promoters independently of the Paf1 complex but then requires this complex for entrance into the coding region of genes in a Pol II-associated manner. In support of a role for Rad6-dependent H2B ubiquitylation in transcription elongation, we find that ubH2B levels are dramatically reduced in strains bearing mutations of the Pol II C-terminal domain (CTD) and abolished by inactivation of Kin28, the serine 5 CTD kinase that promotes the transition from initiation to elongation. Furthermore, synthetic genetic array analysis reveals that the Rad6 complex interacts genetically with a number of known or suspected transcription elongation factors. Finally, we show that Saccharomyces cerevisiae mutants bearing defects in the pathway to H2B ubiquitylation display transcription elongation defects as assayed by 6-azauracil sensitivity. Collectively, our results indicate a role for Rad6 and H2B ubiquitylation during the elongation cycle of transcription and suggest a mechanism by which H3 methylation may be regulated.

[1]  Andrew J Link,et al.  A Protein Complex Containing the Conserved Swi2/Snf2-Related ATPase Swr1p Deposits Histone Variant H2A.Z into Euchromatin , 2004, PLoS biology.

[2]  E. Ezhkova,et al.  Proteasomal ATPases link ubiquitylation of histone H2B to methylation of histone H3. , 2004, Molecular cell.

[3]  Gary D Bader,et al.  Global Mapping of the Yeast Genetic Interaction Network , 2004, Science.

[4]  N. Krogan,et al.  Transitions in RNA polymerase II elongation complexes at the 3′ ends of genes , 2004, The EMBO journal.

[5]  John R Yates,et al.  Deubiquitination of Histone H2B by a Yeast Acetyltransferase Complex Regulates Transcription* , 2004, Journal of Biological Chemistry.

[6]  Wei-Hua Wu,et al.  ATP-Driven Exchange of Histone H2AZ Variant Catalyzed by SWR1 Chromatin Remodeling Complex , 2004, Science.

[7]  Karl Henry,et al.  Rad6 plays a role in transcriptional activation through ubiquitylation of histone H2B. , 2004, Genes & development.

[8]  Huiming Ding,et al.  A Snf2 family ATPase complex required for recruitment of the histone H2A variant Htz1. , 2003, Molecular cell.

[9]  Yi Zhang Transcriptional regulation by histone ubiquitination and deubiquitination. , 2003, Genes & development.

[10]  Nicholas Proudfoot,et al.  Isw1 Chromatin Remodeling ATPase Coordinates Transcription Elongation and Termination by RNA Polymerase II , 2003, Cell.

[11]  Ali Shilatifard,et al.  Transcriptional activation via sequential histone H2B ubiquitylation and deubiquitylation, mediated by SAGA-associated Ubp8. , 2003, Genes & development.

[12]  Stuart L Schreiber,et al.  Methylation of histone H3 K4 mediates association of the Isw1p ATPase with chromatin. , 2003, Molecular cell.

[13]  Wolfgang Fischle,et al.  Binary switches and modification cassettes in histone biology and beyond , 2003, Nature.

[14]  C. Kane,et al.  Running with RNA polymerase: eukaryotic transcript elongation. , 2003, Trends in genetics : TIG.

[15]  Mark Johnston,et al.  The Paf1 Complex Is Essential for Histone Monoubiquitination by the Rad6-Bre1 Complex, Which Signals for Histone Methylation by COMPASS and Dot1p* , 2003, Journal of Biological Chemistry.

[16]  Kevin Struhl,et al.  The Rtf1 Component of the Paf1 Transcriptional Elongation Complex Is Required for Ubiquitination of Histone H2B* , 2003, Journal of Biological Chemistry.

[17]  Mark Gerber,et al.  Transcriptional Elongation by RNA Polymerase II and Histone Methylation* , 2003, Journal of Biological Chemistry.

[18]  G. Cagney,et al.  Methylation of Histone H3 by Set2 in Saccharomyces cerevisiae Is Linked to Transcriptional Elongation by RNA Polymerase II , 2003, Molecular and Cellular Biology.

[19]  Michael Hampsey,et al.  Tails of Intrigue Phosphorylation of RNA Polymerase II Mediates Histone Methylation , 2003, Cell.

[20]  Hien G. Tran,et al.  Chromatin remodeling protein Chd1 interacts with transcription elongation factors and localizes to transcribed genes , 2003, The EMBO journal.

[21]  G. Hartzog,et al.  Transcription elongation by RNA polymerase II. , 2003, Current opinion in genetics & development.

[22]  Masayoshi Iizuka,et al.  Functional consequences of histone modifications. , 2003, Current opinion in genetics & development.

[23]  Christoph H Borchers,et al.  Phosphorylation of RNA polymerase II CTD regulates H3 methylation in yeast. , 2003, Genes & development.

[24]  M. Johnston,et al.  The Paf1 complex is required for histone H3 methylation by COMPASS and Dot1p: linking transcriptional elongation to histone methylation. , 2003, Molecular cell.

[25]  Kevin Struhl,et al.  Targeted recruitment of Set1 histone methylase by elongating Pol II provides a localized mark and memory of recent transcriptional activity. , 2003, Molecular cell.

[26]  J. Yates,et al.  Dual Roles for Spt5 in Pre-mRNA Processing and Transcription Elongation Revealed by Identification of Spt5-Associated Proteins , 2003, Molecular and Cellular Biology.

[27]  Yi Zhang,et al.  Bre1, an E3 ubiquitin ligase required for recruitment and substrate selection of Rad6 at a promoter. , 2003, Molecular cell.

[28]  E. Seto,et al.  Histone modifications. , 2003, Methods.

[29]  G. Cagney,et al.  RNA Polymerase II Elongation Factors of Saccharomyces cerevisiae: a Targeted Proteomics Approach , 2002, Molecular and Cellular Biology.

[30]  Kevin Struhl,et al.  Ubiquitination of Histone H2B by Rad6 Is Required for Efficient Dot1-mediated Methylation of Histone H3 Lysine 79* , 2002, The Journal of Biological Chemistry.

[31]  J. Greenblatt,et al.  Regulation of transcription elongation by phosphorylation. , 2002, Biochimica et biophysica acta.

[32]  J. Jaehning,et al.  Phenotypic analysis of Paf1/RNA polymerase II complex mutations reveals connections to cell cycle regulation, protein synthesis, and lipid and nucleic acid metabolism , 2002, Molecular Genetics and Genomics.

[33]  Mark Johnston,et al.  Methylation of Histone H3 by COMPASS Requires Ubiquitination of Histone H2B by Rad6* , 2002, The Journal of Biological Chemistry.

[34]  S. Berger,et al.  Trans-tail histone modifications: wedge or bridge? , 2002, Nature Structural Biology.

[35]  Brian D. Strahl,et al.  Gene silencing: Trans-histone regulatory pathway in chromatin , 2002, Nature.

[36]  Zu-Wen Sun,et al.  Ubiquitination of histone H2B regulates H3 methylation and gene silencing in yeast , 2002, Nature.

[37]  Kevin Struhl,et al.  Lysine methylation within the globular domain of histone H3 by Dot1 is important for telomeric silencing and Sir protein association. , 2002, Genes & development.

[38]  Philip R. Gafken,et al.  Dot1p Modulates Silencing in Yeast by Methylation of the Nucleosome Core , 2002, Cell.

[39]  S. Squazzo,et al.  The Paf1 complex physically and functionally associates with transcription elongation factors in vivo , 2002, The EMBO journal.

[40]  S. Berger,et al.  Histone modifications in transcriptional regulation. , 2002, Current opinion in genetics & development.

[41]  G. Orphanides,et al.  A Unified Theory of Gene Expression , 2002, Cell.

[42]  F. Winston,et al.  Evidence that Set1, a Factor Required for Methylation of Histone H3, Regulates rDNA Silencing in S. cerevisiae by a Sir2-Independent Mechanism , 2002, Current Biology.

[43]  J. Davie,et al.  Histone H3 lysine 4 methylation is mediated by Set1 and required for cell growth and rDNA silencing in Saccharomyces cerevisiae. , 2001, Genes & development.

[44]  Nevan J. Krogan,et al.  Characterization of a Six-Subunit Holo-Elongator Complex Required for the Regulated Expression of a Group of Genes in Saccharomyces cerevisiae , 2001, Molecular and Cellular Biology.

[45]  C. Allis,et al.  Translating the Histone Code , 2001, Science.

[46]  J. Lis,et al.  High-resolution localization of Drosophila Spt5 and Spt6 at heat shock genes in vivo: roles in promoter proximal pausing and transcription elongation. , 2000, Genes & development.

[47]  J. R. Morris,et al.  Spt5 and spt6 are associated with active transcription and have characteristics of general elongation factors in D. melanogaster. , 2000, Genes & development.

[48]  K. Arndt,et al.  Synthetic lethal interactions suggest a role for the Saccharomyces cerevisiae Rtf1 protein in transcription elongation. , 2000, Genetics.

[49]  Danny Reinberg,et al.  RNA polymerase II elongation through chromatin , 2000, Nature.

[50]  B M Turner,et al.  Histone acetylation and an epigenetic code. , 2000, BioEssays : news and reviews in molecular, cellular and developmental biology.

[51]  C. Allis,et al.  The language of covalent histone modifications , 2000, Nature.

[52]  K. Siegers,et al.  Epitope tagging of yeast genes using a PCR‐based strategy: more tags and improved practical routines , 1999, Yeast.

[53]  R Ohba,et al.  A novel histone acetyltransferase is an integral subunit of elongating RNA polymerase II holoenzyme. , 1999, Molecular cell.

[54]  Richard A. Young,et al.  Activating Phosphorylation of the Kin28p Subunit of Yeast TFIIH by Cak1p , 1999, Molecular and Cellular Biology.

[55]  K. Struhl,et al.  Binding of TBP to promoters in vivo is stimulated by activators and requires Pol II holoenzyme , 1999, Nature.

[56]  J. Recht,et al.  Mutations in both the structured domain and N‐terminus of histone H2B bypass the requirement for Swi–Snf in yeast , 1999, The EMBO journal.

[57]  H. Erdjument-Bromage,et al.  Elongator, a multisubunit component of a novel RNA polymerase II holoenzyme for transcriptional elongation. , 1999, Molecular cell.

[58]  W. Baumeister,et al.  The 26S proteasome: a molecular machine designed for controlled proteolysis. , 1999, Annual review of biochemistry.

[59]  S. Orlicky,et al.  Transcription Elongation through DNA Arrest Sites , 1997, The Journal of Biological Chemistry.

[60]  J. Corden,et al.  Construction and analysis of yeast RNA polymerase II CTD deletion and substitution mutations. , 1995, Genetics.

[61]  S. Reed,et al.  KIN28 encodes a C-terminal domain kinase that controls mRNA transcription in Saccharomyces cerevisiae but lacks cyclin-dependent kinase-activating kinase (CAK) activity , 1995, Molecular and cellular biology.

[62]  O. Ozier-Kalogeropoulos,et al.  A simple and efficient method for direct gene deletion in Saccharomyces cerevisiae. , 1993, Nucleic acids research.

[63]  R. Young,et al.  Functional redundancy and structural polymorphism in the large subunit of RNA polymerase II , 1987, Cell.

[64]  G. Natsoulis,et al.  5-Fluoroorotic acid as a selective agent in yeast molecular genetics. , 1987, Methods in enzymology.