Evidence that the gap junction protein connexin-43 is the ATP-induced pore of mouse macrophages.
Evidence that the gap junction protein connexin-43 is the ATP-induced pore of mouse macrophages.
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DOI：
10.1016/s0021-9258(18)92924-8
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发表时间：
1991-05
期刊：
影响因子：
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通讯作者：
Eric C. Beyer;T. Steinberg
中科院分区：
文献类型：
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作者：
Eric C. Beyer;T. Steinberg
细胞外 ATP4- 在小鼠巨噬细胞和 J774 巨噬细胞样细胞系的质膜上打开孔，允许 fura-2（831 道尔顿）大的分子进入细胞的细胞质基质。 ATP 诱导的孔与间隙连接的功能相似性促使我们检查这些孔是否与间隙连接蛋白连接蛋白家族的成员有关。在高严格条件下，从 J774 细胞中分离的 RNA 与 connexin-43 的 cDNA 杂交，但不与 connexin-32、-26 或 -46 的 cDNA 杂交。从几种不响应细胞外 ATP 透化的变体 J774 细胞系（ATPR 细胞）中分离的 RNA 不与 connexin-43 cDNA 杂交。免疫印迹证明 J774 细胞表达连接蛋白 43 蛋白，但变体 ATPR B2 细胞系不表达。这些研究表明小鼠巨噬细胞表达 connexin-43 间隙连接 mRNA 和蛋白质，并强烈表明在这些细胞中 connexin-43 响应细胞外 ATP4- 形成“半间隙连接”。
Extracellular ATP4- opens pores in the plasma membrane of mouse macrophages and the J774 macrophage-like cell line that allow molecules as large as fura-2 (831 daltons) to enter the cytoplasmic matrix of the cells. The functional similarity of the ATP-induced pores to gap junctions led us to examine whether these pores were related to members of the connexin family of gap junction proteins. Under conditions of high stringency, RNA isolated from J774 cells hybridized with cDNA for connexin-43 but not with cDNA for connexin-32, -26, or -46. RNA isolated from several variant J774 cell lines that do not permeabilize in response to extracellular ATP (ATPR cells) did not hybridize with connexin-43 cDNA. Immunoblots demonstrated that J774 cells, but not the variant ATPR B2 cell line, expressed connexin-43 protein. These studies demonstrate that mouse macrophages express the connexin-43 gap junction mRNA and protein and strongly suggest that in these cells connexin-43 forms “half-gap junctions” in response to extracellular ATP4-.