Mitchell, John L. A.
M.S. (Master of Science)
Department of Biological Sciences
Cellular control mechanisms||Polyamines in the body||Nucleotide sequence||Ornithine decarboxylase
Ornithine Decarboxylase (ODC) is a rate limiting enzyme in the synthesis of the polyamines whose role in the cell includes regulation of DNA replication, transcription and a variety of crucial growth related functions which are still not fully understood. The ODC gene is classified as an oncogene due to its overproduction in most cancerous growth. The DH[sub 23]b cells were derived from HTC rat hepatoma cells using the irreversible inhibitor of ornithine decarboxylase, diflouromethyl ornithine. DH[sub 23]b cells have a very high level of stable, active ODC, half-life of 4-6 hours, in contrast to the parental HTC ODC, which is highly labile, with a half-life of less than 20 minutes. Sequencing was done using the Sanger-Dideoxy method revealing a single base mutation in the DH[sub 23]b ODC gene but not the HTC ODC gene, resulting in the change of a cysteine to a tryptophan at amino acid position 441.
Daghfal, David J., "Sequence of stable ODC in DFMO resistant DH[sub 23]b cells" (1996). Graduate Research Theses & Dissertations. 4884.
iv, 47 pages
Northern Illinois University
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