Flies have four EGF ligands—one called Vn (a neuregulin) and three that are like TGF-α (including Spi). Surprisingly, we found that any of the TGF-α ligands can replace Vn and rescue a mutant. We had to titrate the dose of the TFG-α ligand, because each is more potent that Vn. Our results support the idea that ligand identity is not critical, but that a certain level of signaling is required for the correct cellular response.
We have discovered genetic ways to generate Drosophila cell lines very efficiently. Expression of the Ras oncogene is one very powerful way to do this and we are using the cell lines to find new genes in the Ras pathway. We are using the cells to analyze tumor phenotypes. To enhance the range of possible experiments in Drosophila tissue culture we have developed a protocol to insert single transgenes into the same genomic site using site-specific recombination and a double drug selection.
Paul L, Wang SH, Manivannan SN, Bonanno L, Lewis S, Austin CL, Simcox A. (2013). Dpp-induced Egfr signaling triggers postembryonic wing development in Drosophila. Proc Natl Acad Sci U S A. 110:5058-63. PMID: 2347962
Austin, C.L., Manivannan, S.N., and Simcox, A. (2014). TGF-α ligands can substitute for the neuregulin Vein in Drosophila development. Development 141(21):4110-4. PMID:25336739
Manivannan, S.N., Jacobsen, T.L., Lyon, P., Selvaraj, B., Halpin, P., and Simcox, A. (2015). Targeted Integration of Single-Copy Transgenes in Drosophila melanogaster Tissue-Culture Cells Using Recombination-Mediated Cassette Exchange. Genetics 201: 1319-28. PMID: 26500255
Manivannan, S.N., Lai, L.B, Gopalan, V., and Simcox, A. (2015) Transcriptional control of an essential ribozyme in Drosophila reveals an ancient evolutionary divide in animals. PLoS Genet 11(1): e1004893. doi: 10.1371/journal.pgen.1004893. PMID:25569672
Lim MY, Ng AW, Chou Y, Lim TP, Simcox A, Tucker-Kellogg G, Okamura K. The Drosophila Dicer-1 Partner Loquacious Enhances miRNA Processing from Hairpins with Unstable Structures at the Dicing Site. Cell Rep. 2016 May 24;15(8):1795-808. PMID: 2718483
Fagegaltier D, Falciatori I, Czech B, Castel S, Perrimon N, Simcox A, Hannon GJ. Oncogenic transformation of Drosophila somatic cells induces a functional piRNA pathway. Genes Dev. 2016 Jul 15;30(14):1623-35.
Dequéant, M.L., Fagegaltier, D., Hu, Y., Spirohn, K., Simcox, A., Hannon, G.J., and Perrimon, N. (2015) Discovery of progenitor cell signatures by time-series expression analysis during Drosophila embryonic cell immortalization. Proc Natl Acad Sci U S A. 112: 12974-9. PMID: 26438832
List of Published Work in MyBibliography