MOUSE CX50, A FUNCTIONAL MEMBER OF THE CONNEXIN FAMILY OF GAP JUNCTION PROTEINS, IS THE LENS FIBER PROTEIN MP70
MOUSE CX50, A FUNCTIONAL MEMBER OF THE CONNEXIN FAMILY OF GAP JUNCTION PROTEINS, IS THE LENS FIBER PROTEIN MP70
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DOI：
10.1091/mbc.3.7.711
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发表时间：
1992-07-01
影响因子：
3.3
通讯作者：
PAUL, DL
中科院分区：
文献类型：
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作者：
WHITE, TW;BRUZZONE, R;PAUL, DL
晶体透镜是研究细胞间通讯生物学的一个有吸引力的系统，然而，透镜中缝隙连接结构组分的身份一直存在争议。我们已经克隆了缝隙连接蛋白家族的一个新成员，Cx 50，并且已经表明它可能对应于先前描述的透镜纤维蛋白MP 70。 MP 70的N-末端氨基酸序列与克隆预测的序列密切匹配。Cx 50 mRNA仅在所检测的12个器官中的透镜中检测到，并且这种分布与MP 70蛋白的分布难以区分。针对MP 70的单克隆抗体和针对合成肽产生的抗Cx 50抗体在蛋白质印迹上鉴定相同的蛋白质，并在啮齿动物透镜的冷冻切片上产生相同的免疫荧光模式。我们还表明，Cx 50在配对的爪蟾卵母细胞的表达诱导高水平的电压依赖性电导。这表明Cx 50是连接蛋白家族的功能成员，具有独特的生理特性。随着Cx 50的克隆，透镜中各种细胞类型之间的间隙连接形成的所有已知参与者可用于实验系统中的研究和重建。
The crystalline lens is an attractive system to study the biology of intercellular communication; however, the identity of the structural components of gap junctions in the lens has been controversial. We have cloned a novel member of the connexin family of gap junction proteins, Cx50, and have shown that it is likely to correspond to the previously described lens fiber protein MP70. The N-terminal amino acid sequence of MP70 closely matches the sequence predicted by the clone. Cx50 mRNA is detected only in the lens, among the 12 organs tested, and this distribution is indistinguishable from that of MP70 protein. A monoclonal antibody directed against MP70 and an anti-Cx50 antibody produced against a synthetic peptide identify the same proteins on western blots and produce identical patterns of immunofluorescence on frozen sections of rodent lens. We also show that expression of Cx50 in paired Xenopus oocytes induces high levels of voltage-dependent conductance. This indicates that Cx50 is a functional member of the connexin family with unique physiological properties. With the cloning of Cx50, all known participants in gap junction formation between various cell types in the lens are available for study and reconstitution in experimental systems.