Co-amplification to tail-to-tail copies of MuRVY and IAPE retroviral genomes on the Mus musculus Y chromosome.
We have isolated a clone from a C57BL/6 genomic library that contains both part of the Y Chromosome-specific 8.7 kbp MuRVY genome (Hutchinson and Eicher, J. Virol. 63, 4043, 1989) and a full-length 8.3 kbp Intracisternal A Particle genome (IAPE-Y), in a tail-to-tail organization. Although IAPs are encoded by a disperse multigene family (approximately 1000 copies per haploid genome), we present evidence that a significant proportion of the IAP-related sequences are present on the Y Chromosome (Chr) and that a >25 kbp genomic sequence, which contains the two proviral genomes, has been amplified on the Y Chr. Two discrete amplified families of MuRVY retroviral genomes distinguishable by a polymorphic restriction site were detected, suggestive that amplification occurred in incremental stages. The presence of MuRVY-related DNA sequences, but absence of IAPE-Y-related DNA sequences in Mus spretus suggests that the IAPE-Y retrotransposition event occurred after the evolutionary divergence of the lineages leading to Mus musculus and Mus spretus, and that the amplification of MuRVY occurred independently in the two lineages.
MRC Radiobiology Unit, Chilton, Didcot, Oxon, UK.
J
J
Fennelly
K
K
Harper
S
S
Laval
E
E
Wright
M
M
Plumb
D000818:Animals; D002460:Cell Line; D003001:Cloning, Molecular; D017124:Conserved Sequence / Q000235:genetics; D019143:Evolution, Molecular; D018628:Gene Dosage; D005814:Genes, Viral / Q000235:genetics; D017404:In Situ Hybridization, Fluorescence; D051379:Mice; D008815:Mice, Inbred Strains; D016133:Polymerase Chain Reaction; D011533:Proviruses / Q000235:genetics; D015183:Restriction Mapping; D012190:Retroviridae / Q000235:genetics*; D014998:Y Chromosome / Q000235:genetics*