Evolution of developmental systems underlying segmented body plans of bilaterian imals : insights from studies of segmentation in a cricket TARO MITO
نویسنده
چکیده
AbstracL Remarkable advances in deyelopmental genetics in the pas"wo decades allow us to approach the eyolution of animal design by elucidating the molecular mechanisms underlying diyeTgent body p]ans. The ancestry and eyolution of segmented body plans in the bilaterians has been an active area of inyestigation in this field of study. Although segmentation mechanisms have been extensively studied for the fruit fly Drosophila melanqgaste4 Dresophita exhibits an eyolutionarily deriyed mode of development, and molecular mechanisms underlying Drosophita segmentatio] may be unrepresentatiye for arthropods, eyen for insects. We have been studying the deyelopmental system of the cricket, Gryllus bimaculatus, to anderstand more ancestral and general segmentation mechanisms for insects than those of Drosophila. In GtyUus, anterior segments are specfied a)most simultaneously, whereas posterior segments are specified
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Ancestral functions of Delta/Notch signaling in the formation of body and leg segments in the cricket Gryllus bimaculatus.
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