Thesis (Ph. D.)--University of Missouri--Columbia, 2000. / "May 2000." Typescript. Vita. Includes bibliographical references (leaves 160-169). Also available on the Internet.

Thesis (Ph. D.)--University of Washington, 1996. / Vita. Includes bibliographical references (leaves [95]-102).

Thesis (Ph. D.)--Case Western Reserve University, 2006. / [School of Medicine] Department of Pathology. Includes bibliographical references. Available online via OhioLINK's ETD Center.

Thesis (Ph. D.)--Virginia Commonwealth University, 2006. / Prepared for: Dept. of Microbiology and Immunology. Bibliography: leaves 159-173. Also available online.

Abstract The human and mouse genes POLE1 and Pole1 for the catalytic subunit of DNA polymerase ε contain 51 and 49 exons, respectively, and the human gene POLE2 for the B-subunit contains 19 exons. The human POLE1 encodes three alternatively spliced mRNAs differing in their 5'-terminal sequence and in the N-termini of the predicted proteins. The promoters for the major human transcript and the mouse Pole1 are G+C rich, TATA-less and contain putative cis-acting elements typical of both S phase upregulated and serum responsive promoters. Interestingly, the three human alternative transcripts are expressed from three promoters, and other structural features of POLE1 suggest that regulation of its expression is complicated. The amino acid sequence of the catalytic subunit deduced from the mouse cDNA shows remarkable evolutionary conservation in the DNA polymerase ε family. Interestingly, several conserved elements involved in template-primer binding differ from those of other class B DNA polymerases. This is likely to reflect a distinctive function of the enzyme. The mouse Pole1 was localized to chromosome 5 region E3-E5. The expression of the human POLE2 encoding the B-subunit of DNA polymerase ε is dependent on cell proliferation in a late serum-responsive manner. This is typical for DNA replication-related proteins. The promoter, which utilizes multiple transcriptional initiation sites, is G+C rich and lacks a TATA-box. A 75 bp core promoter region is located within exon 1 and contains an Sp1 element as a critical determinant of the promoter activity. Two overlapping E2F elements adjacent to the Sp1 element are essential for full promoter activity and serum response. Immediately downstream from the core promoter region reside binding sites for E2F1 and NF-1. POLE2 seems to be regulated by two E2F-pocket protein complexes, one associated with Sp1 and the other with NF-1. The complete cDNA of the human DNA topoisomerase IIβ binding protein (TopBP1) reveals a 170 kDa protein that contains eight BRCT-domains and shows homology to S. cerevisiae Dpb11 and S. pombe Cut5/Rad4. The protein interacts physically with human DNA polymerase ε as shown by co-immunoprecipitation. A peptide containing the 6th BRCT-domain and an antibody against this peptide inhibit DNA replication in isolated nuclei, indicating that the protein is required for DNA replication. The expression of TopBP1 is proliferation-dependent in a manner that is typical for replication proteins. The gene encoding TopBP1 was localized to chromosome 3q21-q23.

Drosophila melanoqaster individuals trisomic for an entire chromosome arm can survive to late stages of pupal development. To examine gene expression in these hyperploids, the levels of five enzymes whose structural genes are located on the left arm of chromosome two have been examined both in aneuploid and in diploid strains. Elevated levels of enzyme activity were observed in larvae possessing small segmental duplications for these genes. However, in 2L trisomies, the three distally mapping loci showed compensated levels of expression close to that observed in the diploid strains. Analysis of electrophoretic variants revealed that for one of these compensated loci all three alleles were expressed in trisomies. Two proximally located genes displayed dose-dependent levels of enzyme activity. For most genes, autosomal compensation appears to be very discrete: either the expression of the gene is repressed or it is not. To extend these observations, and to determine if autosomal compensation was peculiar to the left arm of chromosome two, trisomies for the X, for 2R, and for 3L also were examined. Compensating and non-compensating loci were also found on 3L, whereas all loci examined in X-chromosomal trisomies were dosage compensated. This suggests that X-chromosomal and autosomal trisomies are not necessarily analagous. Dosage compensation in X-chromosomal trisomies (metafemales) may occur exclusively or partially by the mechanism that operates between euploid males and females. However, some compensation in X trisomies may occur by regulatory controls distinct from male-female dosage compensation as indicated by the following results. The expression of LSP-1aT a gene that normally escapes complete dosage compensation in diploid males, was fully compensated in trisomic-X larvae. Possibly, compensation of this gene in these individuals was mediated by regulatory mechanisms other than those controlling male-female dosage compensation. As such, loci that normally do not reside on the X chromosome, but which have been transposed to this chromosome, might be expected to escape compensation in metafemales. This appears to be the case; an Adh gene that had been transposed from the second to the X chromosome was expressed at a similar level (per gene) in metafemales and females. In addition, a native X-chromosomal locus appeared to be compensated between males and females, but was not compensated in X-chromosomal trisomies. Thus, some X-linked loci escape regulation by dosage compensation in metafemales. It is possible that some of the regulatory systems operating in X-chromosomal and autosomal trisomies are analagous, and reflect a common form hyperploid compensation. The level at which compensation occured was investigated by measuring the quantities of RNA produced by several genes in whole-arm trisomies. For the heat-shock gene, hsp 85. compensation for protein levels appeared to be Post-transcriptionally regulated. However, measurements of RNA synthesis on salivary gland polytene chromosomes revealed that for most of the genes compensation was transcriptionally regulated. Dosage compensation on the autosomes probably reflects the existence of a system that normally operates in diploids to control gene expression by negative regulation. / Science, Faculty of / Zoology, Department of / Graduate

No description available.

Diss. (sammanfattning) Stockholm : Karol. inst., 2006. / Härtill 4 uppsatser.

Thesis (Ph. D.)--University of Alabama at Birmingham, 2007. / Title from first page of PDF file (viewed Oct. 13, 2008). Includes bibliographical references.

Diss. (sammanfattning) Uppsala : Uppsala universitet, 2009.