高表达钙调素NRK细胞模型的建立及其对细胞生长失调的影响

钙调素作为Ｃａ￣（２＋）信号的主要胞内受体，在细胞增殖调节中起着重要作用。实验中运用ＤＮＡ体外重组技术构建了高表达钙调素的真核载体，并将其转染到大鼠正常肾细胞（ＮＲＫ）中得到钙调素高表达的稳定细胞株。分析表明，高表达钙调素加速细胞生长，促进细胞从Ｇ＿１期向Ｓ期及Ｇ＿２期向Ｍ期的进程，并且使细胞血清依赖性降低，在单层培养中出现接触抑制丧失的岛状生长的现象。基因表达分析表明，原癌基因ｃ－ｆｏｓ、ｃ－ｍｙｃ随钙调素增高而表达加强，这可能是钙调素作用的分子机理之一。

Construction of Overexpressing Calmodulin NRK Cell Line and Its Effects on Cell Growth Disorder

Calmodulin, which is the major intracellular receptor of Ca￣(2+), plays an important role in the regulation of cell proliferation. An eukaryotic vector, which highly expresses calmodulin, was constructed by DNA recombination in vitro and transfected into NRK cells. It showed that overexpressed calmodulin could accelerate cell proliferation, and facilitate the cell progression fromG_1 to S and G_2 to M. The cells, which over-expressed calmodulin,decreased its dependency on serum,and when maintained in monolayer culture they developed dense focies indicating a lost of contact inhibition. The expression of proto-oncogene c-fos and c-myc increased with the calmodulin content,as most likely be part of the molecular mechanisms of the roles of calmodulin.