The major chicken egg envelope protein ZP1 is different from ZPB and is synthesized in the liver
The major chicken egg envelope protein ZP1 is different from ZPB and is synthesized in the liver
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DOI：
10.1074/jbc.275.37.28866
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发表时间：
2000-09-15
影响因子：
4.8
通讯作者：
Wohlrab, F
中科院分区：
文献类型：
--
作者：
Bausek, N;Waclawek, M;Wohlrab, F
脊椎动物卵母细胞周围的细胞外基质在哺乳动物中称为透明膜，在鸟类中称为卵周膜。我们已经分析了这种结构在鸡卵泡和产卵，并确定了一个95 kDa的组成部分的pvm，其中，通过蛋白质测序，显示同源性哺乳动物透明质酸蛋白。令人惊讶的是，我们无法在卵巢颗粒细胞或卵母细胞中检测到这种蛋白质，而是在产蛋母鸡的肝脏中发现了高水平。相反，它在公鸡肝脏中不存在，但可以通过动物的雌激素处理有效地诱导。对肝纤维化-ZAP文库的免疫筛选产生了编码934个氨基酸的蛋白质的cDNA。它与来自其他物种的ZP 1/ZPB家族成员，特别是小鼠和大鼠ZP 1显示出显著的同源性，因此被命名为chkZP 1。它明显不同于先前已保藏在数据库中的命名为chkZPB的蛋白质。ZP 1/ZPB家族的已知成员的比对证明存在至少三个亚组，其中ZP 1和ZPB序列同源组的代表都发生在脊椎动物中。肝脏提取物的北方印迹分析揭示存在编码chkZP 1的单个3.2-磷酸酶mRNA，其不同于卵泡中可检测到的chkZPB转录物。卵泡切片的免疫组织化学分析表明，chkZP 1可以在卵泡膜细胞层的血管中以及卵母细胞周围的卵母细胞中发现。至少一种主要PVM组分在肝脏中合成并通过血流转运到卵泡。
The extracellular matrix surrounding vertebrate oocytes is called the zona pellucida in mammals and perivitelline membrane (pvm) in birds. We have analyzed this structure in chicken follicles and laid eggs and have identified a 95-kDa component of the pvm, which, by protein sequencing, shows homology to mammalian zona pellucida proteins. Surprisingly, we could not detect this protein in ovarian granulosa cells or oocytes but instead found high levels in the liver of the laying hen. In contrast, it is absent in rooster liver but can be efficiently induced by estrogen treatment of the animal. An immunoscreen of a liver lambda-ZAP library yielded a cDNA coding for a protein of 934 amino acids. It displayed significant homology to members of the ZP1/ZPB family from other species, notably to mouse and rat ZP1, and was therefore designated chkZP1, It is clearly different from a protein designated chkZPB that had been deposited in the data base previously. Alignment of the known members of the ZP1/ZPB family demonstrated the existence of at least three subgroups, with representatives of both the ZP1 and the ZPB sequence homology group occurring in vertebrates. Northern blot analysis of liver extracts revealed the presence of a single 3.2-kilobase mRNA coding for chkZP1, distinct from the chkZPB transcript detectable in follicles, Immunohistochemical analysis of follicle sections demonstrates that chkZP1 can be found in the blood vessels of the theca cell layer as well as in the pvm surrounding the oocyte, Thus, in the chicken, at least one of the major pvm components is synthesized in the liver and is transported via the bloodstream to the follicle.