变异链球菌vicK基因调控vicR反义RNA影响胞外多糖代谢  

The vicK gene affects the metabolism of extracellular polysaccharides of Streptococcus mutans by regulating the vicR antisense RNA

作　　者：卓妮娅 邓雅兰 雷蕾[1] 杨英明[1] 胡涛[1] ZHUO Ni-ya;DENG Ya-lan;LEI Lei;YANG Ying-ming;HU Tao(State Key Laboratory of Oral Diseases,National Clinical Research Center for Oral Diseases,Department of Preventive Dentistry,West China Hospital of Stomatology,Sichuan University,Sichiian Chengdu 610041,China)

机构地区：[1]口腔疾病研究国家重点实验室,国家口腔疾病临床医学研究中心,四川大学华西口腔医院预防口腔科,四川成都610041

出　　处：《临床口腔医学杂志》2021年第4期195-200,共6页Journal of Clinical Stomatology

基　　金：国家自然科学基金面上项目(81771068,81800964)。

摘　　要：目的:探讨vicK调控反义RNA ASvicR(Antisense vicR)及gtfB/C/D表达水平,影响变异链球菌胞外多糖代谢的机制。方法:同源重组法构建vicK缺失株及vicK补偿株,通过RT-qPCR检测与变异链球菌UA159标准株比较ASvicR及gtfB/C/D的表达水平差异。通过Western Blot来确定葡糖基转移酶GtfB/C/D的变化;激光共聚焦显微镜及扫描电镜下观测生物膜的结构和致密性。结果:相比UA159,当vicK基因缺失,变异链球菌的ASvicR表达升高,gtfB/C/D表达降低,GtfB/C/D水平降低,生物膜结构松散,致密性降低;而vicK补偿株对于GtfB/C/D亦有调控作用。结论:基因vicK调控GtfB/C/D蛋白表达,vicK缺失使ASvicR表达增高,胞外多糖合成减少,从而降低变异链球菌的致龋性。Objective:To detect the potential mechanisms of gene vicK regulating the expression of Antisense RNA(ASvicR)and gene gtfB/C/D and extracellular polysaccharide metabolism in Streptococcus mutans(S.mutans).Methods:The vicK gene deletion mutant(SmuvicK)was constructed and its complementary mutant by homologous recombination.RT-qPCR was used to detect the expression levels of ASvicR and extracellular polysaccharide related genes compared with S.mutans UA159.The level of glucosyltransferase GtfB/C/D was measured by Western Blot.The structure and density of the S.mutans biofilm were observed by laser confocal microscopy and scanning electron microscopy.Results:When compared with UA159,the expression of ASvicR were increased,gtfB/C/D while GtfB/C/D are decreased,and the biofilm structure was loose in smuvicK.Conclusion:The gene vicK regulates the protein expression of GtfB/C/D.The deletion of vicK increased the expression of ASvicR and decreased the synthesis of extracellular polysaccharide.It is speculated that inhibition of vicK can reduce the cariogenic ability of S.mutans.

关 键 词：变异链球菌 龋病 生物膜 vicK基因 反义RNA 葡糖基转移酶 

分 类 号：R780.2[医药卫生—口腔医学] Q786[医药卫生—临床医学]