Degree Type


Date of Award


Degree Name

Doctor of Philosophy




Molecular, Cellular, and Developmental Biology


The bovine genome is known to contain two main repetitive sequence types. Tandemly repeated satellite sequences represent about 20% and short interspersed repeated sequences 6-10% of the total DNA. No other major classes of repetitive DNA have been detected in the bovine genome. Hybridization kinetic experiments have indicated about 12 kinetic families of the short interspersed repeated DNA sequences (Mayfield, et al., 1980). Evidence presented here shows that these kinetic families are sequence related;Bovine DNA was shotgun cloned into pBR322 and 26 clones containing repetitive DNA were examined. Two of these clones, pPGA7 and pPGB9, were studied in detail. Restriction endonuclease maps indicate that the repetitive unit in each clone is limited to a few hundred base pairs. pPGB9 and 21 out of the remaining 25 clones hybridize to pPGA7. Trace amounts of labelled genomic calf thymus DNA were hybridized with excess clone DNA. The results indicate that the sequence family represented in pPGA7 and pPGB9 comprises about 6% of the genome. This suggests that most, if not all, of the short interspersed repeated sequences in the bovine genome belong to the same sequence family;Both clones were subcloned into bacteriophage M13, and partially sequenced using the method developed by Sanger. A subfragment of pPGA7 was also sequenced by the Maxam-Gilbert method. The DNA sequences resulting from both sequencing methods were compared to each other, to the human Alu sequences, and to a bovine repetitious DNA sequence located near the bovine corticotropin-beta-lipotropin precursor gene (Watanabe, et al., 1982);References;Mayfield, John E., Julie F. McKenna, and Bruce S. Lessa. 1980. The sequence organization of bovine DNA. Chromosoma (Berl.) 76:277-294. Watanabe, Yumiko, Toshihiko Tsukada, Mitsue, Notake, Shigetada Nakanishi, and Shosaku Numa. 1982. Structural analysis of repetitive DNA sequences in the bovine corticotropin-B-lipotropin precursor gene region. Nuc. Acid Res. 10:1459-1469.



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Katherine Anne Koren Richardson



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