title: Identification of DIM-7, a protein required to target the DIM-5 H3 methyltransferase to chromatin.
abstract: Functionally distinct chromatin domains are delineated by distinct posttranslational modifications of histones, and in some organisms by differences in DNA methylation. Proper establishment and maintenance of chromatin domains is critical but not well understood. We previously demonstrated that heterochromatin in the filamentous fungus Neurospora crassa is marked by cytosine methylation directed by trimethylated Lysine 9 on histone H3 (H3K9me3). H3K9me3 is the product of the DIM-5 Lysine methyltransferase and is recognized by a protein complex containing heterochromatin protein-1 and the DIM-2 DNA methyltransferase. To identify additional components that control the establishment and function of DNA methylation and heterochromatin, we built a strain harboring two selectable reporter genes that are silenced by DNA methylation and employed this strain to select for mutants that are defective in DNA methylation (dim). We report a previously unidentified gene (dim-7) that is essential for H3K9me3 and DNA methylation. DIM-7 homologs are found only in fungi and are highly divergent. We found that DIM-7 interacts with DIM-5 in vivo and demonstrated that a conserved domain near the N terminus of DIM-7 is required for its stability. In addition, we found that DIM-7 is essential for recruitment of DIM-5 to form heterochromatin.
authors.affiliation: Institute of Molecular Biology, University of Oregon, Eugene, OR 97403, USA.
authors.forename: Zachary A
authors.initials: ZA
authors.lastname: Lewis
authors.forename: Keyur K
authors.initials: KK
authors.lastname: Adhvaryu
authors.forename: Shinji
authors.initials: S
authors.lastname: Honda
authors.forename: Anthony L
authors.initials: AL
authors.lastname: Shiver
authors.forename: Eric U
authors.initials: EU
authors.lastname: Selker
mesh_terms: D019175:DNA Methylation; D015254:DNA Modification Methylases / Q000235:genetics / Q000378:metabolism*; D006570:Heterochromatin / Q000378:metabolism*; D008780:Methyltransferases / Q000378:metabolism*; D009154:Mutation; D009492:Neurospora crassa / Q000201:enzymology* / Q000235:genetics; D011485:Protein Binding
chemical_list: D006570:Heterochromatin; D015254:DNA Modification Methylases; D008780:Methyltransferases
references.citation: Trends Genet. 2004 Sep;20(9):417-23
references.pmid: 15313550
references.citation: Cell. 2007 Dec 28;131(7):1287-300
references.pmid: 18160038
references.citation: Genetics. 2009 May;182(1):11-23
references.pmid: 19171944
references.citation: Mol Cell Biol. 2006 Nov;26(22):8623-38
references.pmid: 16954381
references.citation: Mol Cell Biol. 2008 Oct;28(19):6044-55
references.pmid: 18678653
references.citation: EMBO J. 2010 Feb 17;29(4):819-29
references.pmid: 20057353
references.citation: Nat Struct Mol Biol. 2008 Apr;15(4):381-8
references.pmid: 18345014
references.citation: Genes Dev. 1997 Sep 15;11(18):2383-95
references.pmid: 9308966
references.citation: Genome Res. 2009 Mar;19(3):427-37
references.pmid: 19092133
references.citation: Methods. 2009 Mar;47(3):142-50
references.pmid: 18950712
references.citation: Genes Dev. 2002 Apr 15;16(8):919-32
references.pmid: 11959841
references.citation: Genetics. 2007 Oct;177(2):1163-71
references.pmid: 17660537
references.citation: Cell. 2001 Dec 28;107(7):905-16
references.pmid: 11779466
references.citation: Nature. 2001 Nov 15;414(6861):277-83
references.pmid: 11713521
references.citation: J Biol. 2004;3(4):18
references.pmid: 15345035
references.citation: J Mol Biol. 2000 Jul 7;300(2):249-73
references.pmid: 10873464
references.citation: Mol Cell Biol. 1986 Jul;6(7):2452-61
references.pmid: 2946938
references.citation: Nat Genet. 2005 Aug;37(8):906-10
references.pmid: 16025112
references.citation: Nature. 2003 Apr 24;422(6934):893-7
references.pmid: 12712205
references.citation: Cell. 2007 Feb 23;128(4):683-92
references.pmid: 17320506
references.citation: J Biol Chem. 2010 Feb 12;285(7):4355-65
references.pmid: 19948733
references.citation: Mol Cell Biol. 2003 Apr;23(7):2379-94
references.pmid: 12640122
references.citation: Genetics. 1997 Jun;146(2):509-23
references.pmid: 9178002
references.citation: Nature. 2007 May 24;447(7143):418-24
references.pmid: 17522675
references.citation: Proc Natl Acad Sci U S A. 2006 Jul 5;103(27):10352-10357
references.pmid: 16801547
references.citation: Nat Protoc. 2007;2(6):1467-78
references.pmid: 17545983
references.citation: Genes Dev. 2005 Jul 15;19(14):1705-14
references.pmid: 16024659
references.citation: Mol Cell. 2004 Feb 13;13(3):427-34
references.pmid: 14967149
references.citation: Nucleic Acids Res. 2008 Jan;36(Database issue):D281-8
references.pmid: 18039703
references.citation: Science. 2004 Jun 25;304(5679):1939
references.pmid: 15218142
references.citation: Nucleic Acids Res. 2000 Jan 1;28(1):231-4
references.pmid: 10592234
references.citation: Nature. 2000 Aug 10;406(6796):593-9
references.pmid: 10949293
references.citation: Nat Rev Genet. 2007 Jan;8(1):35-46
references.pmid: 17173056
references.citation: Science. 2004 Jan 30;303(5658):669-72
references.pmid: 14752161
references.citation: Curr Opin Microbiol. 2007 Apr;10(2):199-203
references.pmid: 17395524
references.citation: Genes Dev. 2008 Dec 15;22(24):3391-6
references.pmid: 19141471
references.citation: Genes Dev. 2007 Sep 15;21(18):2300-11
references.pmid: 17875665