Promoter mutations of mouse mammary tumor virus proviral DNA and characterization of its negative regulatory element /
| Main Author: | |
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| Other Authors: | , |
| Format: | Thesis Book |
| Language: | English |
| Published: |
1990.
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| Subjects: | |
| Online Access: | ProQuest, Abstract Link to OAKTrust copy |
| Abstract: | Transcription from the promoter of mouse mammary tumor virus is subject to induction by several classes of steroid hormones as well as to repression by negative regulatory elements present in the long terminal repeats of proviral DNA. It appears that the overall regulation of MMTV transcription involves a complex interplay of many regulatory and upstream promoter elements. Once these sequence elements are understood individually, the long range goal is to characterize how they interact to establish appropriate levels of gene expression. Two upstream promoter elements (NF-1 and octamer-related sites) were further characterized with a number of site-directed mutations. Three mouse mammary tumor virus promoters with binding sites for nuclear factor 1 having increased binding affinity were constructed. Transcriptional activities of the mutant promoters in a transient transfection assay are not significantly increased relative to the wild-type promoter, indicating that binding of nuclear factor 1 is not rate-determining for transcription from the wild-type promoter in either the presence or absence of glucocorticoid hormones. Transcriptional activation by bound steroid hormone-receptor complexes appears not to be due to facilitating or stabilizing the interaction of nuclear factor 1 with the proviral promoter. A series of six point-mutations were introduced into the octamer region of the mouse mammary tumor virus promoters. Transcriptional activities of the mutant promoters in a transient transfection assay suggest that the functional sequences involved in transcription in this region of the MMTV promoter reside in the octamer-related sequences, and that the portion of the 10 bp repeated elements outside the octamers appears unimportant. They also suggest that a currently uncharacterized novel protein may recognize the octamer region of the MMTV promoter... |
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| Item Description: | Typescript (photocopy). Vita. "Major subject: Biology." |
| Physical Description: | x, 118 leaves : illustrations ; 29 cm |
| Bibliography: | Includes bibliographical references. |