摘要
目的研究细胞周期蛋白依赖性激酶5(CDK5)及其激活剂p35在胰岛β细胞中的表达及作用。方法分别离体培养小鼠胰岛β细胞株、Min6细胞、神经细胞及HEK293细胞,使用RT-PCR、免疫印迹和免疫沉淀等方法检测p35的表达及CDK5活性,并以小鼠胰岛β细胞株、Min6为研究体系,分为正常组(p35组)及p35+Ros组(CDK5活性抑制组),分别检测p35表达、CDK5活性及其对胰岛素分泌的影响。结果①体外培养的胰岛β细胞中,p35在mRNA和蛋白水平均有表达;②p35在胰岛β细胞通过形成CDK5/p35复合物激活CDK5的活性;③过度表达的p35可以使CDK5的活性增加3～4倍,明显抑制胰岛素分泌;④在p35组加入CDK5抑制剂Roscovi-tine(Ros),可抑制p35/CDK5的活性,增加胰岛素的分泌,说明CDK5的活性可抑制胰岛素分泌。结论结果证实p35在胰岛β细胞有表达,并通过激活CDK5的活性、调节胰岛素的分泌,可能在糖尿病胰岛β细胞的损伤机制中起重要作用。
Objective To study the expression and function Of Cdk5 and its activator p35 in pancreatic beta cells. Methods The cul- tured mouse pancreatic beta cell line were used, Mim6 cells, primary cultured neurons and HEK293 cells to observe the difference of p35 expression by using RT-PCR, westem blot and Cdk5 activities in above three cells. And furthermore, Min6 cell line was used as a study system to study the regulated function of Cdk5 activity on insulin secretion. There were three groups： control group （the normal cells）, p35 group （p35 over expression cells） and p35 ＋ Ros group （Cdk5 inhibitor, roseovitine, treated cells）. Results There was p35 expression in beth mRNA and protein level in cultured pancreatic （3 -cell line. Cdk5 activity was detected in pancreatic β-cell line. Cdk5 activity was increased remarkable in p35 over expression cells, and the insulin secretion was inhibited in these cells. Inhibiting Cdk5 activity could rescue the insulin secretion in the roscovitine treated cells. Conclusion There is p35 expression and Cdk5 activity in pancreatic β cell line, Min6 Cells. Cdk5 activity negatively regulates the insulin secretion in pancreatic β- cells. Therefore, Cdk5 n^y play an important role in the diabetic pathogenesis.
出处
《宁夏医学杂志》
CAS
2012年第9期849-852,共4页
Ningxia Medical Journal
基金
国家自然科学基金资助项目(81060066)
宁夏自然科学基金资助项目(NZ10162)
宁夏科技攻关项目(2010168)
宁夏科技攻关国际合作项目(201118)
