Biosynthesis of avian perivitelline membrane ZPC protein and regulation of sperm receptor activity

禽类卵黄周膜由ZPC和ZP1组成，是一种类似于哺乳动物透明带或鱼类绒毛膜的卵母细胞胞外基质。先前的研究表明，其中一种成分，一种与哺乳动物ZPC同源的糖蛋白，在睾酮刺激下，在鹌鹑卵巢发育卵泡的颗粒细胞中产生。然而，对禽类卵黄周膜的另一组分ZP1的分子生物学知之甚少，特别是缺乏有关基因表达的信息。我们克隆了日本鹌鹑的ZP1基因并检测了其基因表达。利用逆转录聚合酶链反应（RT-PCR）和cDNA末端快速扩增技术，从成熟雌鹌鹑肝脏中分离到一段编码ZP1的cDNA。它编码了一个934个氨基酸的蛋白，与鸡的ZP1具有最大的同源性（87%的同源性）。其n端从128到571个氨基酸是独一无二的，因此只有不到40%的氨基酸与其他哺乳动物相同。880个碱基的RT-PCR扩增结果表明，肝脏中的ZP1 mRNA仅局限于成熟的产卵雌性。在未成熟雌性和雄性中，己烯雌酚体内处理刺激了ZP1 mRNA的表达。这些结果提示雄激素和雌激素协同调节鹌鹑卵黄周膜蛋白的形成。此外，还讨论了在雄性或未成熟雌性中使用ZP1转录诱导作为环境雌激素的生物学标记。

Avian perivitelline membrane, an oocyte extracellular matrix homologous to the zona pellucida in mammals or chorion in fish, is composed of ZPC and ZP1. Previous studies have indicated that one of the components, a glycoprotein homologous to mammalian ZPC, is produced in the granulosa cells of the developing follicles of quail ovary on stimulation with testosterone.However, little is known about the molecular biology of the other component of the avian perivitelline membrane, ZP1, and information about gene expression is particularly lacking. We have cloned the ZP1 in Japanese quail and examined its gene expression. A cDNA encoding quail ZP1 was isolated from the livers of mature females using reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends. It encoded a 934-amino acid protein that showed greatest homology (87% identity) with the chicken ZP1. From 128 to 571 amino acid from its N-terminal is unique, so only less than 40% identity with other mammals. RT-PCR amplification of 880 bases indicated that the ZP1 mRNA in the liver was restricted to mature laying females. The expression of ZP1 mRNA was stimulated by in-vivo treatment with diethylstilbestrol in immature females as well as males. These results suggested that androgens and estrogens coordinately regulate the formation of quail perivitelline membrane proteins. In addition, the use of ZP1 transcriptional induction in males or immature females as a biological marker of environmental estrogens is discussed.