高血压相关基因hrg-1在血管平滑肌细胞再分化过程中的表达及功能

研究高血压相关基因hrg 1表达与血管平滑肌细胞 (VSMC)再分化的关系及其在细胞生物学行为调节方面的作用 .采用血清饥饿培养和全反式维甲酸诱导使处于增殖状态的去分化型VSMC再分化 ,观察细胞再分化过程中HRG 1表达变化 ,并探讨其功能 .在血清饥饿和维甲酸诱导VSMC再分化过程中 ,hrg 1基因表达显著上调 ,其表达活性在诱导 2 4h达高峰之后 ,一直维持在较高水平上 ,且其表达量和变化规律与细胞收缩蛋白SMα肌动蛋白和SM2 2α相类似 .免疫共沉淀和免疫双荧光染色结果证实 ,HRG 1抗体可与SMα肌动蛋白共沉淀 ,且两者在同一细胞共定位 .用HRG 1表达质粒转染去分化型VSMC可显著抑制其迁移能力 .结果提示 ,HRG 1在胞质中以与SMα肌动蛋白相互缔合的方式存在 ,其表达与VSMC分化有关 ,该蛋白通过参与细胞骨架构成而调节VSMC收缩与迁移

Expression and Function of Hypertension Related Gene hrg-1 During Redifferentiation of Vascular Smooth Muscle Cells

The relationship between the expression of hypertension related gene hrg 1 and the redifferentiation of vascular smooth muscle cell (VSMC) as well as the HRG 1 function in regulating cellular biological behavior were studied. During the redifferentiation of the dedifferentiated VSMCs caused by serum withdrawal and the induction of all trans retinoic acid (atRA), hrg 1 gene expression and its function were determined by RT PCR, Western blotting and cell migration assay. The results indicated that hrg 1 gene expression increased significantly during VSMC redifferentiation, and reached the peak after VSMCs being induced for 24 hours by serum deprivation and atRA, and was then maintained at a higher level. The changes of HRG 1 mRNA and protein were similar to those of cellular contractile proteins SM α actin and SM22α. It was demonstrated that anti HRG 1 antibody could be co precipitated with SM α actin, and these two proteins were co localized in one cell, as shown by co immunofluorescence staining with HRG 1 and SM α actin. Migration ability of VSMCs was dramatically suppressed after being transfected with HRG 1 expression plasmid. It was suggested that HRG 1 was associated with SM α actin in cytoplasm, and its expression was related with VSMC differentiation, and HRG 1 participated in construction of cytoskeleton and regulated contraction and migration of VSMCs.