Putrescine and PHAS-I expression / by Karin Andrea Suess.
| Author/creator | Suess, Karin Andrea author. |
| Other author | Seidel, Edward (Edward R.), degree supervisor. |
| Other author | East Carolina University. Department of Biology. |
| Format | Theses and dissertations |
| Production | 1998. |
| Description | 42 leaves : illustrations ; 28 cm |
| Supplemental Content | Access via ScholarShip |
| Subjects |
| Summary | The polyamines putrescine, spermidine, and spermine are organic cations that function in cell proliferation in prokaryotic and eukaryotic cells. Depletion of polyamines using a highly specific suicide substrate inhibitor (5mM DFMO), causes growth arrest in G1 phase of cell cycle. Cells are capable of resuming their normal growth after exogenous addition of polyamines. Hence, polyamine levels play a critical role in cell proliferation. This study focused on examining the PHAS-I mRNA in IEC-6 cells that were treated with either polyamines (10uM putrescine), inhibitors of polyamine synthesis, or mitogenic factors. Total RNA was extracted and examined by Northern blot analysis with antisense riboprobes. An internal control (beta-actin) for quantitative measurement of gene expression was also used. IEC-6 cells with a normal complement of polyamine had no change in PHAS-1 mRNA levels after treatment with 10uM putrescine for 24 hours. In addition. IEC-6 cells treated with 5mM DFMO for 72 hours, exhibited no change in PHAS-I mRNA levels. In cells with a normal complement of endogenous polyamines, 10nM IGF-1 had no effect on PHAS-I expression. In contrast, however, cells that were depleted of polyamines by DFMO evidenced a 50% decrease in the level of PHAS-I mRNA in response to 10(mu)M putrescine. This suggests that putrescine may play a role in regulation of the PHAS-I mRNA. Whether or not the effect of putrescine on PHAS-I mRNA transcripts is related to putrescine-mediated negative feedback control of ornithine decarboxylase (ODC) translation cannot be determined with confidence from these results. In summary, these data show that under certain, but not all, conditions putrescine modulates either the expression or the stability of the PHAS-I message. |
| General note | Submitted to the faculty of the Department of Biology. |
| General note | Advisor: Edward R. Seidel |
| Dissertation note | M.S. East Carolina University 1998 |
| Bibliography note | Includes bibliographical references (leaves 38-42). |
| Genre/form | dissertations. |
| Genre/form | Academic theses. |
| Genre/form | Academic theses. |
| Genre/form | Thèses et écrits académiques. |
Availability
| Library | Location | Call Number | Status | Item Actions |
|---|---|---|---|---|
| Joyner | University Archives | ASK AT SPECIAL COLLECTIONS DESK | ✔ Available | Request Material |
| Electronic Resources | Access Content Online | ✔ Available |