The Journal of Heredity 1999:90(3)
© 1999 The American Genetic Association 90:418-422
Characterization and chromosomal distribution of satellite DNA sequences of the water buffalo (Bubalus bubalis)
Laboratory of Animal Genetics, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya, Japan 1College of Veterinary Medicine, University of the Phillippines at Los Banos, College, Laguna, The Phillippines *Corresponding author e-mail: tnami@agr.nagoya-u.ac.jp.
Satellite DNA sequences were isolated from the water buffalo (Bubalus bubalis) after digestion with two restriction endonucleases, BamHl and Stul. These satellite DNAs of the water buffalo were classified into two types by sequence analysis: one had an approximately 1,400 bp tandem repeat until with 79% similarity to the bovine satellite I DNA; the other had an approximately 700 bp tandem repeat unit with 81% similarity to the bovine satellite II DNA. The chromosomal distribution of the satellite DNAs were examined in the river-type and the swamp-type buffaloes with direct R-banding fluorescence in situ hybridization. Both the buffalo satellite DNAs were localized to the centromeric regions of all chromosomes in the two types of buffaloes. The hybridization signals with the buffalo satellite I DNA on the acrocentric autosomes and X chromosome were much stronger than that on the biarmed autosomes and Y chromosome, which corresponded to the distribution of C-band-positive centromeric heterochromatin. This centromere-specific satellite DNA also existed in the interstitial region of the long arm of chromosome 1 of the swamp-type buffalo, which was the junction of the telomere-centromere tandem fusion that divided the karyotype in the two types of buffaloes. The intensity of the hybridization signals with buffalo satellite II DNA was almost the same over all the chromosomes, including the Y chromosome, and no additional hybridization signal was found in noncentromeric sites.