title: upSET, theDrosophilahomologue of SET3, Is Required for Viability and the Proper Balance of Active and Repressive Chromatin Marks.
abstract: Chromatin plays a critical role in faithful implementation of gene expression programs. Different post-translational modifications (PTMs) of histone proteins reflect the underlying state of gene activity, and many chromatin proteins write, erase, bind, or are repelled by, these histone marks. One such protein is UpSET, theDrosophilahomolog of yeast Set3 and mammalian KMT2E (MLL5). Here, we show that UpSET is necessary for the proper balance between active and repressed states. Using CRISPR/Cas-9 editing, we generated S2 cells that are mutant forupSETWe found that loss of UpSET is tolerated in S2 cells, but that heterochromatin is misregulated, as evidenced by a strong decrease in H3K9me2 levels assessed by bulk histone PTM quantification. To test whether this finding was consistent in the whole organism, we deleted theupSETcoding sequence using CRISPR/Cas-9, which we found to be lethal in both sexes in flies. We were able to rescue this lethality using a taggedupSETtransgene, and found that UpSET protein localizes to transcriptional start sites (TSS) of active genes throughout the genome. Misregulated heterochromatin is apparent by suppressed position effect variegation of thewm4allele in heterozygousupSET-deleted flies. Using nascent-RNA sequencing in theupSET-mutant S2 lines, we show that this result applies to heterochromatin genes generally. Our findings support a critical role for UpSET in maintaining heterochromatin, perhaps by delimiting the active chromatin environment.
authors.affiliation: Division of Genetics, Brigham and Women's Hospital, Boston, Massachusetts 02115.|Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115.|Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts 02138.
authors.forename: Kyle A
authors.initials: KA
authors.lastname: McElroy
authors.affiliation: Division of Genetics, Brigham and Women's Hospital, Boston, Massachusetts 02115.|Center for Biomedical Informatics, Harvard Medical School, Boston, Massachusetts 02115.
authors.forename: Youngsook L
authors.initials: YL
authors.lastname: Jung
authors.affiliation: Division of Genetics, Brigham and Women's Hospital, Boston, Massachusetts 02115.|Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115.
authors.forename: Barry M
authors.initials: BM
authors.lastname: Zee
authors.affiliation: Division of Genetics, Brigham and Women's Hospital, Boston, Massachusetts 02115.|Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115.
authors.forename: Charlotte I
authors.initials: CI
authors.lastname: Wang
authors.affiliation: Division of Genetics, Brigham and Women's Hospital, Boston, Massachusetts 02115.|Center for Biomedical Informatics, Harvard Medical School, Boston, Massachusetts 02115.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Park
authors.affiliation: Division of Genetics, Brigham and Women's Hospital, Boston, Massachusetts 02115 mkuroda@genetics.med.harvard.edu.|Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115.
authors.forename: Mitzi I
authors.initials: MI
authors.lastname: Kuroda
mesh_terms: D000818:Animals; D064113:CRISPR-Cas Systems; D002843:Chromatin / Q000235:genetics*; D055012:Chromosomal Position Effects / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000235:genetics; D029721:Drosophila Proteins / Q000096:biosynthesis / Q000235:genetics*; D004331:Drosophila melanogaster / Q000235:genetics; D005786:Gene Expression Regulation; D049750:Genome, Insect; D006570:Heterochromatin / Q000235:genetics*; D059014:High-Throughput Nucleotide Sequencing; D006655:Histone Deacetylases / Q000235:genetics; D006657:Histones / Q000235:genetics; D006801:Humans; D009687:Nuclear Proteins / Q000235:genetics*; D011499:Protein Processing, Post-Translational / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics; D017385:Sequence Homology
chemical_list: D002843:Chromatin; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D006570:Heterochromatin; D006657:Histones; C460660:KMT2E protein, human; D009687:Nuclear Proteins; D029701:Saccharomyces cerevisiae Proteins; C000624895:UpSET protein, Drosophila; C511735:Set3 protein, S cerevisiae; D006655:Histone Deacetylases
keywords: Drosophila; MLL5; SET3; chromatin; heterochromatin; position effect variegation; upSET