黑腹果蝇的银色基因编码多种与哺乳动物激素原加工酶相似的羧肽酶。

Settle S H, Green M M, Burtis K C

Section of Molecular and Cellular Biology, University of California, Davis 95616, USA.

Proc Natl Acad Sci U S A. 1995 Oct 10;92(21):9470-4. doi: 10.1073/pnas.92.21.9470.

The silver (svr) gene of Drosophila melanogaster is required for viability, and severe mutant alleles result in death prior to eclosion. Adult flies homozygous or hemizygous for weaker alleles display several visible phenotypes, including cuticular structures that are pale and silvery in color due to reduced melanization. We have identified and cloned the DNA encoding the svr gene and determined the sequence of several partially overlapping cDNAs derived from svr mRNAs. The predicted amino acid sequence of the polypeptides encoded by these cDNAs indicates that the silver proteins are members of the family of preprotein-processing carboxypeptidases that includes the human carboxypeptidases E, M, and N. One class of svr mRNAs is alternatively spliced to encode at least two polyproteins, each of which is composed of two carboxypeptidase domains.

黑腹果蝇的银色（svr）基因是生存所必需的，严重的突变等位基因会导致羽化前死亡。对于较弱等位基因纯合或半合子的成年果蝇表现出几种可见的表型，包括由于黑色素沉着减少而颜色苍白且呈银色的表皮结构。我们已经鉴定并克隆了编码svr基因的DNA，并确定了几个源自svr mRNA的部分重叠cDNA的序列。这些cDNA编码的多肽的预测氨基酸序列表明，银色蛋白是前体蛋白加工羧肽酶家族的成员，该家族包括人羧肽酶E、M和N。一类svr mRNA经过可变剪接以编码至少两种多蛋白，每种多蛋白由两个羧肽酶结构域组成。