Molecular and biological characterization of a zonula occludens-1 homologue in Hydra vulgaris, named HZO-1.
Molecular and biological characterization of a zonula occludens-1 homologue in Hydra vulgaris, named HZO-1.
复制标题
寻常水螅中的 zonula occlusionns-1 同源物（名为 HZO-1）的分子和生物学特征。
DOI：
10.1007/s004270000103
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发表时间：
2000
期刊：
影响因子：
--
通讯作者：
SarrasJr,MP
中科院分区：
文献类型：
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作者：
Fei,K;Yan,L;Zhang,J;SarrasJr,MP
封闭小带-1（ZO-1）是最早发现的紧密连接的分子组成部分之一。序列分析已经将ZO-1置于更广泛的膜相关鸟苷酸激酶（MAGUK）蛋白家族中，该蛋白家族包含诸如突触后密度95（PSD-95）、果蝇盘细胞大肿瘤抑制基因产物（dlg-A）、p55和TamA等不同成员。在脊椎动物和无脊椎动物中的研究已经确定MAGUK家族参与各种各样的细胞功能。这些功能涉及调节细胞过程，如：（1）紧密连接形成，（2）细胞增殖，（3）细胞分化，和（4）神经元突触传递。HydraZO-1（HZO-1）是由一个约6.0 kb的信使RNA（mRNA）编码，含有一个5,085 bp的开放阅读框架。该蛋白质分子量为191 kDa，具有MAGUK结构域特征，包括PSD-95/SAP 90、大圆盘、ZO-1（PDZ）结构域、SH 3结构域和GUK结构域。使用由HZO-1序列设计的合成肽产生的抗体的蛋白质印迹分析证实了适当质量的α Hydroprotein的存在。而整体安装原位杂交确定，HZO-1 mRNA表达沿着整个纵向轴ofHydra，横截面分析确定，HZO-1 mRNA的表达仅限于外胚层或外细胞层的有机体的上皮双层。与这种mRNA表达模式一致，免疫荧光研究将HZO-1蛋白定位于外胚层细胞的顶端质膜。目前还不清楚HZ 0 -1在水螅细胞生理学中的作用;然而，免疫定位研究表明，它具有保守的质膜相关功能，正如其他无脊椎动物和脊椎动物物种中的对应物所报道的那样。这些研究表明，MAGUK家族的蛋白质与膜相关的功能出现在后生动物进化的早期，甚至在原口动物和后口动物的分歧。
Zonula occludens-1 (ZO-1) is one of the earliest identified molecular components of tight junctions. Sequence analysis has placed ZO-1 into the broader membrane-associated guanylate kinase (MAGUK) protein family that contains such diverse members as postsynaptic density 95 (PSD-95),Drosophiladiscs large tumor suppressor gene product (dlg-A), p55, and TamA. Studies in both vertebrates and invertebrates have established that the MAGUK family is involved in a wide variety of cellular functions. These functions involve the regulation of such cellular processes as: (1) tight junction formation, (2) cell proliferation, (3) cell differentiation, and (4) neuronal synapse transmission. Extending these studies, we report the presence of a ZO-1 homologue inHydra vulgaris, a member of the Cnidaria, the second oldest phylum of the animal kingdom.HydraZO-1 (HZO-1) is encoded by a single messenger RNA (mRNA) of approximately 6.0 kb that contains an open reading frame of 5,085 bp. The 191 kDa predicted protein consists of a characteristic MAGUK domain structure, including three PSD-95/SAP90, discs-large, ZO-1 (PDZ) domains, asrchomology (SH3) domain, and a guanylate kinase (GUK) domain. Western blot analysis using an antibody generated from a synthetic peptide designed from the HZO-1 sequence confirmed the presence of aHydraprotein of the appropriate mass. While whole mount in situ hybridization determined that HZO-1 mRNA was expressed along the entire longitudinal axis ofHydra, cross-sectional analysis established that HZO-1 mRNA expression was restricted to the ectoderm or outer cell layer of the organism’s epithelial bilayer. Consistent with this mRNA expression pattern, immunofluorescence studies localized HZO-1 protein to the apical plasma membrane of ectodermal cells. It is unclear what role HZ0-1 has in the cellular physiology ofHydra; however, immunolocalization studies indicate a conserved plasma membrane-associated function(s), as reported for its counterparts in other invertebrate and vertebrate species. These studies establish that the MAGUK family of proteins with a membrane-associated function arose early during metazoan evolution, even before the divergence of protostomes and deuterostomes.