Identification of EBP50: A PDZ-containing phosphoprotein that associates with members of the ezrin-radixin-moesin family.
Identification of EBP50: A PDZ-containing phosphoprotein that associates with members of the ezrin-radixin-moesin family.
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DOI：
10.1083/jcb.139.1.169
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发表时间：
1997-10-06
影响因子：
7.8
通讯作者：
Bretscher, A
中科院分区：
文献类型：
--
作者：
Reczek, D;Berryman, M;Bretscher, A
膜-细胞骨架连接蛋白的ezrin-radixin-moesin（ERM）家族的成员具有分别与质膜和肌动蛋白细胞骨架相关联的NH 2-和COOH-末端结构域。为了寻找可能参与膜结合的ERM结合伴侣，将组织裂解物在埃兹蛋白和膜突蛋白的固定化NH 2-末端结构域上进行亲和层析，所述结构域包含埃兹蛋白-根蛋白-膜突蛋白-结合结构域（N-ERMAD）。来自人胎盘的50-53 kD多肽和来自牛脑的58-59 kD多肽的集合直接与两种N-ERMAD结合。50-53-kD胎盘蛋白迁移作为一个主要的50-kD物种磷酸酶处理后，表明异质性是由于不同的磷酸化状态。我们将这些多肽称为ERM结合磷蛋白50（EBP 50）。使用人EBP 50的序列分析来鉴定编码357个残基的多肽的102-kb人cDNA。重组EBP 50与埃兹蛋白和膜突蛋白的N-ERMAD紧密结合。来自脑候选物的肽序列表明其与EBP 50密切相关。EBP 50具有两个PSD-95/DlgA/ZO-1样（PDZ）结构域，并且最可能是兔蛋白辅因子的同源物，其参与蛋白激酶A对肾刷状缘Na+/H+交换的调节。EBP 50广泛分布于组织中，并且在含有极化上皮的组织中特别富集。培养的细胞和组织的免疫荧光显微镜显示，EBP 50与肌动蛋白和埃兹蛋白共定位在上皮细胞的顶端微绒毛，和免疫电镜表明，它是专门与胎盘合胞体滋养层的微绒毛。此外，EBP 50和ezrin可以从分离的人胎盘微绒毛中共免疫沉淀为复合物。这些发现表明，EBP 50是一种生理相关的埃兹蛋白结合蛋白。由于已知PDZ结构域介导与整合膜蛋白的结合，因此埃兹蛋白的一种膜附着模式可能通过EBP 50介导。
Members of the ezrin-radixin-moesin (ERM) family of membrane–cytoskeletal linking proteins have NH2- and COOH-terminal domains that associate with the plasma membrane and the actin cytoskeleton, respectively. To search for ERM binding partners potentially involved in membrane association, tissue lysates were subjected to affinity chromatography on the immobilized NH2-terminal domains of ezrin and moesin, which comprise the ezrin-radixin-moesin–association domain (N-ERMAD). A collection of polypeptides at 50–53 kD from human placenta and at 58-59 kD from bovine brain bound directly to both N-ERMADs. The 50–53-kD placental proteins migrated as a major 50-kD species after phosphatase treatment, indicating that the heterogeneity is due to different phosphorylation states. We refer to these polypeptides as ERM-binding phosphoprotein 50 (EBP50). Sequence analysis of human EBP50 was used to identify an ∼2-kb human cDNA that encodes a 357-residue polypeptide. Recombinant EBP50 binds tightly to the N-ERMADs of ezrin and moesin. Peptide sequences from the brain candidate indicated that it is closely related to EBP50. EBP50 has two PSD-95/DlgA/ZO-1–like (PDZ) domains and is most likely a homologue of rabbit protein cofactor, which is involved in the protein kinase A regulation of the renal brush border Na+/H+ exchanger. EBP50 is widely distributed in tissues, and is particularly enriched in those containing polarized epithelia. Immunofluorescence microscopy of cultured cells and tissues revealed that EBP50 colocalizes with actin and ezrin in the apical microvilli of epithelial cells, and immunoelectron microscopy demonstrated that it is specifically associated with the microvilli of the placental syncytiotrophoblast. Moreover, EBP50 and ezrin can be coimmunoprecipitated as a complex from isolated human placental microvilli. These findings show that EBP50 is a physiologically relevant ezrin binding protein. Since PDZ domains are known to mediate associations with integral membrane proteins, one mode of membrane attachment of ezrin is likely to be mediated through EBP50.
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影响因子：
64.8
作者：
KIM, E;NIETHAMMER, M;SHENG, M
通讯作者：
SHENG, M
影响因子：
11.4
作者：
Dransfield, DT;Bradford, AJ;Goldenring, JR
通讯作者：
Goldenring, JR
DOI：
10.1073/pnas.90.22.10846
发表时间：
1993-11-15
影响因子：
11.1
作者：
GARY, R;BRETSCHER, A
通讯作者：
BRETSCHER, A
影响因子：
7.8
作者：
HENRY, MD;AGOSTI, CG;SOLOMON, F
通讯作者：
SOLOMON, F
影响因子：
2.9
作者：
OAKLEY, BR;KIRSCH, DR;MORRIS, NR
通讯作者：
MORRIS, NR