Enhancement of connexin 43 expression increases proliferation and differentiation of an osteoblast-like cell line
Enhancement of connexin 43 expression increases proliferation and differentiation of an osteoblast-like cell line
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DOI：
10.1006/excr.2000.5145
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发表时间：
2001-04-01
影响因子：
3.7
通讯作者：
Schirrmacher, K
中科院分区：
文献类型：
--
作者：
Gramsch, B;Gabriel, HD;Schirrmacher, K
当骨细胞通过主要由连接蛋白43(Cx43)组成的缝隙连接连接时，它们形成一个功能性的合胞体。为了进一步了解Cx43在骨细胞生长和分化中的作用，我们用含有大鼠Cx43基因的表达载体将Cx43稳定地导入表达Cx45的UMR 106-01细胞，对3个稳定表达Cx43和/或Cx45的克隆进行了分析，免疫细胞化学和Northern blotting均显示Cx43和/或Cx45的表达发生了明显的变化。双倍全细胞膜片钳显示单通道电导分别为20ps(Cx45)和60ps(Cx43)。Cx43的过表达导致染料偶联增加，并伴随着缝隙连接电导的升高。与对照组相比，转基因克隆的表型特征是增殖增加(4-7倍)。此外，Cx43表达增强10~12倍的转基因克隆显示细胞外基质钙含量显著增加，矿化结节增大，碱性磷酸酶适度增加。我们得出结论，通过Cx43增强的缝隙连接偶联显著促进了UMR细胞的增殖和分化。(C)2001年学术出版社。
Bone cells form a functional syncytium as they are coupled by gap junctions composed mainly of connexin 43 (Cx43). To further understand the role of Cx43 in bone cell growth and differentiation, we stably transfected Car45-expressing UMR 106-01 cells with Cx43 using an expression vector containing rat Cx43 cDNA Three stably transfected clones were analyzed, all of which showed altered expression of Cx43 and/or Cx45 as was obvious from immunocytochemistry and Northern blotting. Double whole-cell patch clamping revealed single-channel conductances of 20 (Cx45) and 60 pS (Cx43). The overexpression of Cx43 led to an increase in dye coupling concomitant with elevated gap-junctional conductance. The phenotype of the transfected clones was characterized by an increased proliferation (4- to 7-fold) compared to controls. Moreover, a transfectant clone with 10- to 12-fold enhanced Cx43 expression showed a significantly increased calcium content of the extracellular matrix and enlarged mineralization nodules, while alkaline phosphatase was moderately increased. We conclude that enhanced gap-junctional coupling via Cx43 significantly promotes proliferation and differentiation of UMR cells. (C) 2001 Academic Press.