A chromosomal basis for the differential organization of a porcine centromere-specific repeat.
Digestion of porcine DNA with the restriction enzymes SnoI and BamHI and subsequent gel electrophoresis revealed the presence of a repeat fragment of approximately 340 bp in length. When this fragment was cloned and used to probe a Southern blot containing pig DNA that had been digested with various enzymes, a ladder pattern of bands based on a unit of 340 bp was observed. Three individual BamHI repeat units were sequenced; each monomer unit was approximately 90% identical in sequence to the other two monomers. Double digestion did not alter the ladder pattern, indicating a differential distribution of restriction enzyme sites within the repeat family. We demonstrate by Southern blotting of DNAs from a panel of pig x rodent hybrid cell lines that the differential restriction site distribution has a chromosomal basis. We show that this repeat family hybridizes to the centromeres of all pig chromosomes other than the Y chromosome. However, when stringency was raised, hybridization persisted only to certain metacentric chromosomes.
Agricultural and Food Research Council, Institute of Animal Physiology and Genetics Research Cambridge UK.
J R
JR
Miller
J
J
Hindkjaer
P D
PD
Thomsen
D000818:Animals; D015139:Blotting, Southern; D002503:Centromere; D002875:Chromosomes; D004247:DNA / Q000235:genetics / Q000302:isolation & purification; D004262:DNA Restriction Enzymes; D006822:Hybrid Cells; D017404:In Situ Hybridization, Fluorescence; D051379:Mice; D008969:Molecular Sequence Data; D012091:Repetitive Sequences, Nucleic Acid; D013552:Swine
D004247:DNA; D004262:DNA Restriction Enzymes