Detection and cloning of an X-linked locus associated with a NotI site that is not methylated on mouse inactivated X chromosome by the RLGS-M method.
In looking for genes that escape X chromosome inactivation, we scanned the methylation status of genomic DNA from XX, X0, and XY mice using the method of restriction landmark genomic scanning using methylation-sensitive endonuclease. We detected and cloned a candidate locus and identified the Orf1 gene. Orf1 has sequence similarities to the B2 repetitive element and human CXORF4 (formerly called EXLM1), which escapes X inactivation. The B2 element spans the 3' terminus of the ORF and the 3' UTR of Orf1. The Orf1 gene encompasses 18.5 kb of genomic DNA including 11 exons and 10 introns. Taking advantage of genomic polymorphisms present between MSM and C3H/He, we showed that murine Orf1 is mapped to the proximal region of the X chromosome. Despite the unmethylation of the NotI site, Orf1 is subject to X inactivation.
Takada
S
S
Graduate School of Environmental Earth Science, Hokkaido University, North 10 West 5 Kita-ku, Sapporo, 060-0810, Japan.
Kamiya
M
M
Arima
T
T
Kagebayashi
H
H
Shibata
H
H
Muramatsu
M
M
Chapman
V M
VM
Wake
N
N
Hayashizaki
Y
Y
Takagi
N
N
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D018899:CpG Islands; D019175:DNA Methylation; D015252:Deoxyribonucleases, Type II Site-Specific; D004303:Dosage Compensation, Genetic; D005260:Female; D015870:Gene Expression; D008040:Genetic Linkage; D006801:Humans; D008297:Male; D051379:Mice; D008969:Molecular Sequence Data; D011506:Proteins / Q000235:genetics*; D012333:RNA, Messenger / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors; D014960:X Chromosome
C122171:Med14 protein, mouse; D011506:Proteins; D012333:RNA, Messenger; D014157:Transcription Factors; D015252:Deoxyribonucleases, Type II Site-Specific; C038565:GCGGCCGC-specific type II deoxyribonucleases