title: Differential methylation persists at the mouse Rasgrf1 DMR in tissues displaying monoallelic and biallelic expression.
abstract: A subset of mammalian genes exhibits genomic imprinting, whereby one parental allele is preferentially expressed. Differential DNA methylation at imprinted loci serves both to mark the parental origin of the alleles and to regulate their expression. In mouse, the imprinted gene Rasgrf1 is associated with a paternally methylated imprinting control region which functions as an enhancer blocker in its unmethylated state. Because Rasgrf1 is imprinted in a tissue-specific manner, we investigated the methylation pattern in monoallelic and biallelic tissues to determine if methylation of this region is required for both imprinted and non-imprinted expression. Our analysis indicates that DNA methylation is restricted to the paternal allele in both monoallelic and biallelic tissues of somatic and extraembryonic lineages. Therefore, methylation serves to mark the paternal Rasgrf1 allele throughout development, but additional factors are required for appropriate tissue-specific regulation of expression at this locus.
authors.affiliation: Department of Biology, Bryn Mawr College, Bryn Mawr, PA 19010-2899, USA.
authors.forename: Lauren
authors.initials: L
authors.lastname: Dockery
authors.forename: Jennifer
authors.initials: J
authors.lastname: Gerfen
authors.forename: Christina
authors.initials: C
authors.lastname: Harview
authors.forename: Charlotte
authors.initials: C
authors.lastname: Rahn-Lee
authors.forename: Rachel
authors.initials: R
authors.lastname: Horton
authors.forename: Yaena
authors.initials: Y
authors.lastname: Park
authors.forename: Tamara L
authors.initials: TL
authors.lastname: Davis
mesh_terms: D000483:Alleles; D000818:Animals; D018899:CpG Islands / Q000235:genetics; D019175:DNA Methylation; D004622:Embryo, Mammalian / Q000378:metabolism; D005260:Female; D018392:Genomic Imprinting; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D010920:Placenta / Q000378:metabolism; D013094:Spermatozoa / Q000378:metabolism; D024363:Transcription Initiation Site; D014158:Transcription, Genetic; D020666:ras-GRF1 / Q000235:genetics* / Q000378:metabolism
chemical_list: C513037:Rasgrf1 protein, mouse; D020666:ras-GRF1