In this project it has been shown that <I>Myosin heavy chain at 95F (Mhc95F)</I> and the <I>Broad-complex (BR-C) </I>are the target genes of two <I>Gal4 </I>lines which show asymmetric follicle cell expression patterns. <I>Mhc95F, </I>which encodes <I>Drosophila </I>myosin 95F, a class VI unconventional myosin, is expressed in the anterior follicle cells, including the follicle cells undergoing centripetal migration and dorsal-anterior migration. P-element mediated mutagenesis has been undertaken to create mutations in the <I>Mhc95F </I>gene. Several lines showing deletions in the chromosomal 95F region have been obtained. However, no strong evidence shows that the mutant phenotype of these lines and the <I>Mhc95F </I>gene are directly related. Additionally, targeted silencing technique has been used for the study of its function during development. Using a transformed fly line which contains the antisense <I>Mhc95F</I> gene downstream of the Gal4 binding sequences, UAS, to cross with a tissue-specific <I>Gal4</I> line, the progeny exhibit the malformed leg and unexpanded wing phenotype. Moreover, the female progeny from the cross have disrupted centripetal migration of the follicle cells, and degenerated egg chambers. These results indicate that myosin 95F is likely to be involved in cell shape change and cell migration during development. The target gene of line C726b is the <I>BR-C</I>, which encodes a family of zinc-finger transcription factors and plays a key role in metamorphosis. During stage 10b of oogenesis, <I>BR-C</I> mRNA is present in two groups of follicle cells over the lateral-dorsal-anterior ooctye. This expression domain is related to its function in dorsal appendage morphogenesis, and this is confirmed by studying the eggshell phenotype of partial "loss-of-function" <I>BR-C</I> mutants and heat-stock inducible <I>BR-C</I> transgenic fly lines. Expression of the <I>BR-C </I>in the lateral-dorsal-anterior follicle cells is specified by the Gurken/Torpedo(DER) signalling pathway along the D/V axis in a dose-dependent manner.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:649481 |
| Date | January 1997 |
| Creators | Deng, Wu-Min |
| Publisher | University of Edinburgh |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://hdl.handle.net/1842/13617 |
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