RRC ID 46721
Author Gu SG, Fire A.
Title Partitioning the C. elegans genome by nucleosome modification, occupancy, and positioning.
Journal Chromosoma
Abstract We have characterized two post-translational histone modifications in Caenorhabditis elegans on a genomic scale. Micrococcal nuclease digestion and immunoprecipitation were used to obtain distinct populations of single nucleosome cores, which were analyzed using massively parallel DNA sequencing to obtain positional and coverage maps. Two methylated histone H3 populations were chosen for comparison: H3K4 histone methylation (associated with active chromosomal regions) and H3K9 histone methylation (associated with inactivity). From analysis of the sequence data, we found nucleosome cores with these modifications to be enriched in two distinct partitions of the genome; H3K4 methylation was particularly prevalent in promoter regions of widely expressed genes, while H3K9 methylation was enriched on specific chromosomal arms. For each of the six chromosomes, the highest level of H3K9 methylation corresponds to the pairing center responsible for chromosome alignment during meiosis. Enrichment of H3K9 methylation at pairing centers appears to be an early mark in meiotic chromosome sorting, occurring in the absence of components required for proper pairing of homologous chromosomes. H3K9 methylation shows an intricate pattern within the chromosome arms with a particular anticorrelation to regions that display a strong approximately 10.5 bp periodicity of AA/TT dinucleotides that is known to associate with germline transcription. By contrast to the global features observed with H3K9 methylation, H3K4 methylation profiles were most striking in their local characteristics around promoters, providing a unique promoter-central landmark for 3,903 C. elegans genes and allowing a precise analysis of nucleosome positioning in the context of transcriptional initiation.
Volume 119(1)
Pages 73-87
Published 2010-2-1
DOI 10.1007/s00412-009-0235-3
PMID 19705140
PMC PMC2805775
MeSH Animals Caenorhabditis elegans / cytology Caenorhabditis elegans / genetics* Caenorhabditis elegans / metabolism Caenorhabditis elegans Proteins / genetics Caenorhabditis elegans Proteins / metabolism Chromatin Assembly and Disassembly* Genome* Histones / genetics Histones / metabolism Meiosis Methylation Nucleosomes / genetics* Nucleosomes / metabolism
IF 3.442
Times Cited 46
C.elegans tm574