Casso David J, Tanda Soichi, Biehs Brian, Martoglio Bruno, Kornberg Thomas B
Department of Biochemistry and Biophysics, University of California, San Francisco, 94143, USA.
Genetics. 2005 May;170(1):139-48. doi: 10.1534/genetics.104.039933. Epub 2005 Feb 16.
We identified the Drosophila melanogaster Signal peptide peptidase gene (Spp) that encodes a multipass transmembrane aspartyl protease. Drosophila SPP is homologous to the human signal peptide peptidase (SPP) and is distantly related to the presenilins. We show that, like human SPP, Drosophila SPP can proteolyze a model signal peptide and is sensitive to an SPP protease inhibitor and that it localizes to the endoplasmic reticulum. Expression of Drosophila SPP was first apparent at germ band extension, and in late embryos it was robust in the salivary glands, proventriculus, and tracheae. Flies bearing mutations in conserved residues or carrying deficiencies for the Spp gene had defective tracheae and died as larvae.
我们鉴定出了果蝇（Drosophila melanogaster）的信号肽肽酶基因（Spp），该基因编码一种多次跨膜天冬氨酸蛋白酶。果蝇的信号肽肽酶（SPP）与人类信号肽肽酶（SPP）同源，并且与早老素存在远缘关系。我们发现，与人类SPP一样，果蝇SPP能够蛋白水解一种模型信号肽，并且对一种信号肽肽酶抑制剂敏感，而且它定位于内质网。果蝇SPP的表达最初在胚带延伸时明显可见，在晚期胚胎中，它在唾液腺、前胃和气管中表达强烈。在保守残基上发生突变或携带Spp基因缺陷的果蝇，气管存在缺陷，并在幼虫阶段死亡。
