tailieunhanh - Báo cáo khoa học: Systemic RNAi of the cockroach vitellogenin receptor results in a phenotype similar to that of the Drosophila yolkless mutant

During vitellogenesis, one of the most tightly regulated processes in ovipar-ous reproduction, vitellogenins are incorporated into the oocyte through vitellogenin receptor (VgR)-mediated endocytosis. In this paper, we report the cloning of the VgR cDNA from Blattella germanica, as well as the first functional analysis of VgR following an RNA interference (RNAi) approach. | ềFEBS Journal Systemic RNAi of the cockroach vitellogenin receptor results in a phenotype similar to that of the Drosophila yolkless mutant Laura Ciudad Maria-Dolors Piulachs and Xavier Belles Department of Physiology and Molecular Biodiversity. Institute of Molecular Biology of Barcelona Barcelona Spain Keywords Blattella germanica panoistic ovaries vitellogenin receptor yolkless Correspondence . Piulachs and X. Belles Department of Physiology and Molecular Biodiversity Institute of Molecular Biology of Barcelona CSIC Jordi Girona 18 08034 Barcelona Spain Fax 34 932045904 Tel 34 934006124 E-mail mdpagr@ xbragr@ Received 6 October 2005 revised 16 November 2005 accepted 18 November 2005 During vitellogenesis one of the most tightly regulated processes in oviparous reproduction vitellogenins are incorporated into the oocyte through vitellogenin receptor VgR -mediated endocytosis. In this paper we report the cloning of the VgR cDNA from Blattella germanica as well as the first functional analysis of VgR following an RNA interference RNAi approach. We characterized the VgR VgR mRNA and protein expression patterns in pre-adult and adult stages of this cockroach as well as VgR immunolocalization in ovarioles belonging to the panoistic type. We then specifically disrupted VgR gene function using RNAi techniques. Knockdown of VgR expression led to a phenotype characterized by low yolk content in the ovary and high vitellogenin concentration in the haemolymph. This phenotype is equivalent to that of the yolkless mutant of Drosophila melanogaster which have the yl VgR gene disrupted. The results additionally open the perspective that development genes can be functionally analyzed via systemic RNAi in this basal species. doi From worms to chickens vitellogenesis is one of the most emblematic processes related to reproduction in oviparous animals. By this process yolk proteins produced by vitellogenic tissues usually .