摘要
目的研究变形链球菌临床分离株质子移位膜ATP酶(F-ATPase)的γ亚基基因uncG的遗传多态性和mRNA表达水平。方法选取在不同龋敏感人群中分离的18株高耐酸和20株低耐酸变形链球菌为实验株,扩增uncG基因,行限制性内切酶长度多态性(RFLP)分析和测序比较,应用RT-PCR法和凝胶成像系统定量软件对20株不同基因型和不同耐酸力变形链球菌uncG基因的mRNA表达水平进行评价和比较。结果ALuⅠ-RFLP和BsrⅠ-RFLP产生A、B、C、D 4种基因型,但4种基因型在不同耐酸力菌株的分布差异没有统计学意义(P>0.05)。不同基因型及不同耐酸力菌株uncG的mRNA表达水平不同,但其差异也没有统计学意义(P>0.05)。结论变形链球菌F-ATPaseγ亚基基因uncG的RFLP基因型和mRNA表达水平具有明显遗传异质性,但对菌株耐酸力没有明显影响。
Objective To study the genetic diversity and the gene expression of membrane-bound proton-translocating ATPase（F-ATPase） subunit gene uncG derived from Streptococcus mutans （S.mutans） clinical isolates. Methods 38 S.mutm~ strains derived from caries-active and caries-free individuals including 18 strains displaying high acid tolerance and 20 strains displaying low acid tolerance. Gene uncG was amplified with specific primers from S.mutans genomic DNA, then the PCR product was analyzed by RFLP and sequenced. The relative expression quantity of uncG gene against the housekeeping gene recA was determined by using RT-PCR method. A gel documentation system and QUANTITY ONES software were used to analyze the data results. Results It was testified that four genotypes A, B, C and D of PCR-RFLP were revealed when respectively digested with Alu Ⅰ and Bsr Ⅰ , but the distributions of the four genotype strains showed no difference （P〉0.05）. The differences of uncG gene transcript quantities derived from different genotype or different aciduranc strains had no significance （P〉0.05）. Conclusion This study indicated that uncG gene of F-ATPase obviously displayed genetic diversity and existed pelymorphism at mRNA expression level, while the Alu Ⅰ -RFLP genotypes and the expression levels would not be responsive to different acid tolerance of S.mutans strains.
出处
《华西口腔医学杂志》
CAS
CSCD
北大核心
2007年第1期1-4,共4页
West China Journal of Stomatology
基金
国家自然科学基金资助项目(30171013)
贵州省自然科学基金资助项目[黔科合计(2004)3055]
贵州省优秀科技人才省长专项基金资助项目[(2005)244]
关键词
变形链球菌
质子移位膜ATP酶
耐酸性
基因多态性
Streptococcus mutans
membrane-bound proton-translocating ATPase
acid tolerance
genetic diversity
