Replication timing properties within the mouse distal chromosome 7 imprinting cluster.
Genomic imprinting is characterized by allele-specific expression of genes within chromosomal domains. Here we show, using fluorescence in situ hybridization (FISH) analysis, that the large chromosomal domain of the mouse distal chromosome 7 imprinting cluster, approximately 1 Mb in length between p57Kip2 and H19 genes, replicates asynchronously between the two alleles during S-phase. At the telomeric side of this domain, we found a transition from asynchronous replication at the imprinted p57Kip2 gene to synchronous replication at the Nap2 gene. Two-color FISH suggested that the paternal allele of this whole domain replicates earlier than its maternal allele. Treatment of the cells with a histone deacetylase inhibitor abolished this allele-specific feature accompanied with accelerated replication of the later-replicating allele at a domain level. Allele-specific asynchronous replication was observed even in ES cells. These results suggest that this imprinting cluster consists of a large replication domain which is already found at the early stage in development.
Kagotani
Kazuhiro
K
Laboratory of Molecular and Cellular Biology, Faculty of Bioresources, Mie University, Tsu, Japan.
Takebayashi
Shin-ichiro
S
Kohda
Atsushi
A
Taguchi
Hiroshi
H
Paulsen
Martina
M
Walter
Jörn
J
Reik
Wolf
W
Okumura
Katsuzumi
K
D000483:Alleles; D000818:Animals; D002453:Cell Cycle / Q000187:drug effects; D002874:Chromosome Mapping; D004791:Enzyme Inhibitors / Q000494:pharmacology; D018392:Genomic Imprinting; D056572:Histone Deacetylase Inhibitors; D017404:In Situ Hybridization, Fluorescence; D051379:Mice
D004791:Enzyme Inhibitors; D056572:Histone Deacetylase Inhibitors