title: X-chromosome silencing in the germline of C. elegans.
abstract: Germline maintenance in the nematode C. elegans requires global repressive mechanisms that involve chromatin organization. During meiosis, the X chromosome in both sexes exhibits a striking reduction of histone modifications that correlate with transcriptional activation when compared with the genome as a whole. The histone modification spectrum on the X chromosome corresponds with a lack of transcriptional competence, as measured by reporter transgene arrays. The X chromosome in XO males is structurally analogous to the sex body in mammals, contains a histone modification associated with heterochromatin in other species and is inactivated throughout meiosis. The synapsed X chromosomes in hermaphrodites also appear to be silenced in early meiosis, but genes on the X chromosome are detectably expressed at later stages of oocyte meiosis. Silencing of the sex chromosome during early meiosis is a conserved feature throughout the nematode phylum, and is not limited to hermaphroditic species.
authors.affiliation: Biology Department, Emory University, Atlanta, GA 30322, USA.
authors.forename: William G
authors.initials: WG
authors.lastname: Kelly
authors.forename: Christine E
authors.initials: CE
authors.lastname: Schaner
authors.forename: Abby F
authors.initials: AF
authors.lastname: Dernburg
authors.forename: Min-Ho
authors.initials: MH
authors.lastname: Lee
authors.forename: Stuart K
authors.initials: SK
authors.lastname: Kim
authors.forename: Anne M
authors.initials: AM
authors.lastname: Villeneuve
authors.forename: Valerie
authors.initials: V
authors.lastname: Reinke
mesh_terms: D000818:Animals; D017173:Caenorhabditis elegans / Q000166:cytology / Q000196:embryology* / Q000235:genetics*; D012734:Disorders of Sex Development; D005260:Female; D018507:Gene Expression Regulation, Developmental; D020868:Gene Silencing; D017930:Genes, Reporter; D005854:Germ Cells / Q000502:physiology*; D006066:Gonads / Q000502:physiology; D006657:Histones / Q000378:metabolism*; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D008540:Meiosis; D008745:Methylation; D020411:Oligonucleotide Array Sequence Analysis; D009865:Oocytes / Q000502:physiology; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D013094:Spermatozoa / Q000502:physiology; D014158:Transcription, Genetic; D019076:Transgenes; D014960:X Chromosome / Q000235:genetics* / Q000378:metabolism
chemical_list: D006657:Histones; D011993:Recombinant Fusion Proteins