title: Arabidopsis AtMORC4 and AtMORC7 Form Nuclear Bodies and Repress a Large Number of Protein-Coding Genes.
abstract: The MORC family of GHKL ATPases are an enigmatic class of proteins with diverse chromatin related functions. In Arabidopsis, AtMORC1, AtMORC2, and AtMORC6 act together in heterodimeric complexes to mediate transcriptional silencing of methylated DNA elements. Here, we studied Arabidopsis AtMORC4 and AtMORC7. We found that, in contrast to AtMORC1,2,6, they act to suppress a wide set of non-methylated protein-coding genes that are enriched for those involved in pathogen response. Furthermore, atmorc4 atmorc7 double mutants show a pathogen response phenotype. We found that AtMORC4 and AtMORC7 form homomeric complexes in vivo and are concentrated in discrete nuclear bodies adjacent to chromocenters. Analysis of an atmorc1,2,4,5,6,7 hextuple mutant demonstrates that transcriptional de-repression is largely uncoupled from changes in DNA methylation in plants devoid of MORC function. However, we also uncover a requirement for MORC in both DNA methylation and silencing at a small but distinct subset of RNA-directed DNA methylation target loci. These regions are characterized by poised transcriptional potential and a low density of sites for symmetric cytosine methylation. These results provide insight into the biological function of MORC proteins in higher eukaryotes.
authors.affiliation: Department of Molecular, Cell and Developmental Biology, University of California at Los Angeles, Los Angeles, California, United States of America.
authors.forename: C Jake
authors.identifier: 0000-0001-5120-0377
authors.initials: CJ
authors.lastname: Harris
authors.affiliation: Department of Molecular, Cell and Developmental Biology, University of California at Los Angeles, Los Angeles, California, United States of America.
authors.forename: Dylan
authors.initials: D
authors.lastname: Husmann
authors.affiliation: Department of Molecular, Cell and Developmental Biology, University of California at Los Angeles, Los Angeles, California, United States of America.
authors.forename: Wanlu
authors.initials: W
authors.lastname: Liu
authors.affiliation: Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America.
authors.forename: Farid El
authors.identifier: 0000-0003-2434-4660
authors.initials: FE
authors.lastname: Kasmi
authors.affiliation: Basic Forestry and Proteomics Research Center, Haixia Institute of Science and Technology (HIST), Fujian Agriculture and Forestry University, Fuzhou, Fujian, China.|Fujian Province Key Laboratory of Plant Virology, Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, Fujian, China.
authors.forename: Haifeng
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Molecular, Cell and Developmental Biology, University of California at Los Angeles, Los Angeles, California, United States of America.
authors.forename: Ashot
authors.initials: A
authors.lastname: Papikian
authors.affiliation: Department of Molecular, Cell and Developmental Biology, University of California at Los Angeles, Los Angeles, California, United States of America.
authors.forename: William A
authors.initials: WA
authors.lastname: Pastor
authors.affiliation: Department of Molecular, Cell and Developmental Biology, University of California at Los Angeles, Los Angeles, California, United States of America.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Moissiard
authors.affiliation: Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California, United States of America.
authors.forename: Ajay A
authors.initials: AA
authors.lastname: Vashisht
authors.affiliation: Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America.|Howard Hughes Medical Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America.
authors.forename: Jeffery L
authors.initials: JL
authors.lastname: Dangl
authors.affiliation: Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California, United States of America.
authors.forename: James A
authors.initials: JA
authors.lastname: Wohlschlegel
authors.affiliation: Department of Molecular, Cell and Developmental Biology, University of California at Los Angeles, Los Angeles, California, United States of America.|Howard Hughes Medical Institute, University of California at Los Angeles, Los Angeles, California, United States of America.
authors.forename: Steven E
authors.initials: SE
authors.lastname: Jacobsen
mesh_terms: D000251:Adenosine Triphosphatases / Q000096:biosynthesis / Q000235:genetics*; D017360:Arabidopsis / Q000235:genetics; D029681:Arabidopsis Proteins / Q000096:biosynthesis / Q000235:genetics*; D019175:DNA Methylation / Q000235:genetics; D044127:Epigenesis, Genetic; D018506:Gene Expression Regulation, Plant; D005810:Multigene Family / Q000235:genetics; D010641:Phenotype; D014158:Transcription, Genetic
chemical_list: D029681:Arabidopsis Proteins; D000251:Adenosine Triphosphatases