Methylation imprinting was observed of mouse mo-2 macrosatellite on the pseudoautosomal region but not on chromosome 9.
Mouse mo-2 macrosatellites consisting of 31-bp tandem repeat units are mainly located at two loci in the C57BL/6 genome, one being at the centromere-distal telomeric region of chromosome 9 and the other at the pseudoautosomal (PA) region of chromosomes X and Y. The two clusters constitute approximately 300 kb and 150 kb, respectively. Southern analysis of a methylation-sensitive enzyme, HpaII-digested DNA showed that the mo-2 macrosatellites are detected as more than 30 polymorphic bands. Comparison of those bands between reciprocally crossed F1 mice revealed that approximately 20% of the allele-specific fragments exhibit different band intensities depending on the sex of the parent of origin. The differential methylation is observed in the mo-2 macrosatellite on the PA region but not in that on chromosome 9. Several fragments including the 3.4-kb fragment without internal HpaII site are more clearly detected when paternally derived, suggesting that the male-derived macrosatellite is undermethylated. Interestingly, the difference is much more remarkable in inter-subspecific F1 mice between C57BL/6 and MSM than F1 between C57BL/6 and C3H/He. This suggests the presence of a modifier(s) that affect(s) the methylation of mo-2 in the MSM genome.
Takahashi
Y
Y
First Department of Biochemistry, Niigata University School of Medicine, Japan.
Mitani
K
K
Kuwabara
K
K
Hayashi
T
T
Niwa
M
M
Miyashita
N
N
Moriwaki
K
K
Kominami
R
R
D000818:Animals; D001483:Base Sequence; D002875:Chromosomes / Q000378:metabolism; D003433:Crosses, Genetic; D004247:DNA / Q000737:chemistry; D004276:DNA, Satellite / Q000378:metabolism*; D005260:Female; D008040:Genetic Linkage; D018392:Genomic Imprinting; D008297:Male; D008745:Methylation; D051379:Mice; D008815:Mice, Inbred Strains; D008969:Molecular Sequence Data; D012091:Repetitive Sequences, Nucleic Acid
D004276:DNA, Satellite; D004247:DNA