Miller J R, Hindkjaer J, Thomsen P D
Agricultural and Food Research Council, Institute of Animal Physiology and Genetics Research Cambridge UK.
Cytogenet Cell Genet. 1993;62(1):37-41. doi: 10.1159/000133441.
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.
用限制性内切酶SnoI和BamHI消化猪DNA并随后进行凝胶电泳，结果显示存在一个长度约为340 bp的重复片段。当该片段被克隆并用于探测含有用各种酶消化过的猪DNA的Southern印迹时，观察到基于340 bp单位的条带梯形模式。对三个单独的BamHI重复单位进行了测序；每个单体单位在序列上与其他两个单体大约90%相同。双酶切并未改变梯形模式，这表明重复家族内限制性酶切位点的分布存在差异。我们通过对一组猪×啮齿动物杂种细胞系的DNA进行Southern印迹证明，限制性酶切位点的差异分布具有染色体基础。我们表明，这个重复家族与除Y染色体外的所有猪染色体的着丝粒杂交。然而，当严格度提高时，杂交仅持续存在于某些中着丝粒染色体上。
