Perry A C, Gichuhi P M, Jones R, Hall L
Department of Biochemsitry, University of Bristol, School of Medical Sciences, U.K.
Biochem J. 1995 May 1;307 ( Pt 3)(Pt 3):843-50. doi: 10.1042/bj3070843.
The fertilin complex, a heterodimeric surface membrane glycoprotein found on the head region of mammalian spermatozoa, has been reported to mediate membrane fusion with the egg plasma membrane during fertilization. We have employed PCR to generate products corresponding to monkey (Macaca fascicularis) fertilins from testis cDNA. These PCR products have been used to isolate full-length fertilin cDNA clones corresponding to both alpha and beta subunits. Both monkey fertilin alpha and beta cDNAs encode proteins which belong to an expanding family of metalloproteinase-like, disintegrin-like, cysteine-rich, mammalian proteins. Surprisingly, cDNAs for two fertilin alpha isoforms, alpha I and alpha II, were isolated, encoding proteins of 905 and 825 residues respectively. The predicted fertilin alpha isoforms share extensive identity, but differ significantly towards their N- and C-termini, suggesting the possibility of more than one type of fertilin complex in primates. Alignment of monkey alpha and beta fertilins with their respective guinea-pig counterparts suggests a high level of overall structural conservation throughout, whilst providing new insights into the domain function of each.
受精素复合体是一种在哺乳动物精子头部区域发现的异二聚体表面膜糖蛋白，据报道在受精过程中它介导精子与卵质膜的膜融合。我们利用聚合酶链反应（PCR）从睾丸cDNA中生成了与猕猴（食蟹猴）受精素相对应的产物。这些PCR产物已被用于分离对应于α和β亚基的全长受精素cDNA克隆。猕猴受精素α和β cDNA都编码属于一个不断扩大的金属蛋白酶样、解整合素样、富含半胱氨酸的哺乳动物蛋白家族的蛋白质。令人惊讶的是，分离出了两种受精素α同工型αI和αII的cDNA，分别编码905和825个残基的蛋白质。预测的受精素α同工型具有广泛的同一性，但在其N端和C端有显著差异，这表明在灵长类动物中可能存在不止一种类型的受精素复合体。将猕猴α和β受精素与其各自的豚鼠对应物进行比对表明，它们在整体结构上高度保守，同时为每个结构域的功能提供了新的见解。
