In this study, we hypothesize that human acidic mammalian chitinase (AMCase) binds and is regulated by the epidermal growth factor receptor (EGFR), and that AMCase interacts with Galectin-3 (Gal-3) to mediate anti-apoptotic functions. We further hypothesize that asthma-associated polymorphisms of AMCase alter chitinase activity and modulate anti-apoptotic effects. We investigated the interactions between AMCase, Gal-3 and EGFR by establishing binding and co-expression in vitro; apoptotic effects were evaluated via Annexin V/Propidium Iodide staining. Molecular cloning was performed to generate single nucleotide polymorphisms (SNPs) of AMCase associated with asthma. Our data showed that co-expression of AMCase and EGFR induces chitinase activity; we found that AMCase and Gal-3 bind each other in vitro, and that they co-localize in the cytoplasm of cells. Co-transfection of AMCase and Gal-3 demonstrates greater anti-apoptotic effect than Gal-3 alone, while recombinant Gal-3 induces apoptosis, which is not blocked by incubation with recombinant AMCase. From these data, we conclude that AMCase is regulated by EGFR, and that AMCase and Gal-3 physically interact, however contrary to our hypothesis, the anti-apoptotic effects of AMCase are unlikely to be mediated by Gal-3. Further exploration of this pathway using SNP constructs generated in this study will shed light on the mechanism of AMCase in asthma.
| Identifer | oai:union.ndltd.org:YALE_med/oai:ymtdl.med.yale.edu:etd-03102009-162717 |
| Date | 28 September 2009 |
| Creators | Wachtel, Heather |
| Contributors | Jack Elias |
| Publisher | Yale University |
| Source Sets | Yale Medical student MD Thesis |
| Language | English |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://ymtdl.med.yale.edu/theses/available/etd-03102009-162717/ |
| Rights | restricted, I hereby grant to the Yale School of Medicine the non-exclusive license to photocopy, archive and make accessible, under the conditions specified below, my print and electronic thesis, in whole or in part, in all forms of media. <p> I agree that the Yale School of Medicine may electronically store, copy or translate my thesis to any medium or format for the purpose of preservation and accessibility. The Yale School of Medicine is not under obligation to reproduce or display my thesis in the same format in which it was originally deposited. <p> I retain all ownership rights to the thesis, including but not limited to the right to use in future works (such as articles and books) all or part of this thesis. |
Page generated in 0.0025 seconds