Cloning and Estrogen Regulation of the Retinol Binding Protein Messenger-Rna of Xenopus Laevis

Our laboratory is studying the mechanisms by which the hormone, estrogen, regulates gene expression in the frog, Xenopus laevis. In this thesis, I described the isolation of a full length cDNA clone for an estrogen induced mRNA isolated from the liver of Xenopus laevis. By DNA sequencing and subsequent homology alignment with the sequence for human retinol binding protein, the clone was identified as the mRNA for serum retinol binding protein of Xenopus. Since we wished to use this gene to study hormone regulation, it was important to establish its hormone regulation in vivo. Therefore, I conducted an extensive series of experiments to characterize the pattern of hormone response. The results provided dramatic departures from the pattern seen for vitellogenin in that: (1) estrogen induction of RBP mRNA is very long-lived, (2) the persistent elevated abundance is dependent on estrogen receptor, and (3) that the estrogen induction is antagonized by testosterone. In addition to the regulation of the gene's expression imposed by hormones, I have shown that the gene is expressed only in the liver of the animal. Finally, I conducted a study of the RBP gene induction in embryos, where the protein's ligand, retinol, is likely to play an important role in differentiation. The findings of these investigations indicate that the RBP gene is activated coordinately with liver ontogeny and RBP gene activation may be a very early event in hepatocyte differentiation.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Biochemistry

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2014

Author dc:creator

• Mckearin, Dennis Martin

• Biology, Molecular

Identifier

(UMI)AAI8701562

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/70558