碩士 / 國立臺灣大學 / 動物學研究所 / 89 / During dorsal closure in Drosophila, cells of the lateral epidermis migrate over the amnioserosa to encase the embryo. At least three classes of characterized dorsal-opened group gene products, which function in the epidermis, are involved in the process. Class I genes code for structural proteins. Class II genes encode Drosophila Jun amino (N)-terminal kinase (DJNK) signaling molecule and Class III genes encode Decapentaplegic (Dpp)-mediated signaling molecules.
A newly discovered embryonic lethal gene, shrimp ball (shpb), encodes a transcription factor with highly conserved BTB/POZ domain. Severe dorsal closure defect was found in shpb mutants. shpb expresses mainly in amnioserosa, indicating its function in amnioserosa. shpb mutation caused lose of two DJNK target gene expression. Dorsal-opened phenotype caused by shpb can be rescued by ubiquitous expression of dpp and mutation of raw. raw mutation also converts the ventral denticles to naked cuticle in shpb mutants. From the observation, we postulate that shpb is acting at the upstream position of the DJNK signaling and positively regulates an unknown initial signal, which is responsible for activation of the dorsal process. shpb may also link the gap between function of dorsal closure and amnioserosa, where is suggested to be the site emitting dorsal closure signal.
shpb is also postulated to act in the EGFR (Epidermal Growth Factor Receptor) signaling pathway. shpb mutation causes disappearance of EGFR-dependent Fasciclin III (Fas III) expression, indicating its positive role in EGFR signaling.
| Identifer | oai:union.ndltd.org:TW/089NTU00312015 |
| Date | January 2001 |
| Creators | Yu-Ping Yang, 楊宇平 |
| Contributors | Tze-Bin Chou, 周子賓 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 72 |
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