【摘要】 目的研究链霉素对结核分枝杆菌非编码sRNA表达量的影响,探讨sRNA是否参与细菌与药物的相互作用。方法基于结核分枝杆菌标准菌株H37Rv的高通量测序结果,选出表达量估计值较高的4个sRNA作为研究对象,根据链霉素的最小抑菌浓度(MIC)对标准菌株H37Rv进行不同浓度和不同时间的链霉素诱导,提取各组菌液的总RNA,通过实时定量逆转录聚合酶链反应(qRT-PCR)检测4种sRNA在各组中的表达量,比较不同抑菌浓度和不同时间的链霉素作用下sRNA的表达量差异。结果当链霉素浓度在1/2MIC时对结核分枝杆菌的生长产生明显抑制作用;在4种sRNA中,MTS2823表达量最高,F6表达量相对较低;MTS1338在4MIC浓度的链霉素处理18 h即出现表达上调;在4MIC浓度链霉素作用6 d后,MTS1338和mcr11表达量分别出现(4.80±1.14)倍和(2.91±0.86)倍上调,而MTS2823表达下调。在各组药物处理组中F6表达量的变化均不明显。结论链霉素对结核分枝杆菌sRNA的表达可产生促进或抑制作用,提示sRNA可对某些基因进行转录后调控,促进或拮抗链霉素对结核分枝杆菌的作用。更多还原

【Abstract】 Objective To analyze the effect of streptomycin on the expression of sRNAs,and to explore whether small RNAs are involved in the interactions between drugs and bacteria. Methods Small RNAs were selected according to the expression level based on RNA-seq data of H37 Rv. Clean data were mapped to genome（ M. tuberculosis H37 Rv NC₀00962. 3） and FPKM（ fragments per kilobase of exon per million fragments） was calculated to estimate the expression level of each gene. Different groups of M. tuberculosis H37 Rv were cultured at different streptomycin concentrations at different time points. Afterwards,total RNA of each group was isolated,and qRT-PCR was used to detect the expression of the sRNAs-F6,mcr11,MTS1338 and MTS2823. Data were analyzed to compare the expression changes of 4 sRNAs at different time points and different concentrations of streptomycin. Results Four sRNAs were selected,which were annotated as non-coding RNA by NCBI and had a high estimated expression level. The MIC of streptomycin on H37 Rv was0. 5 g / ml. A concentration of streptomycin above 1 /2MIC could obviously suppress the growth of H37 Rv. Among the four types of sRNAs,MTS2823 had the highest expression while F6 and MTS1338 had a lower expression level. The expression of these sRNAs changed very little at the concentration of 1 /4MIC and 1 /2MIC. In the group of 4MIC for 18 hours,only MTS1338 was upregulated. In the group of 4MIC for 6 days,the level of MTS1338 and mcr11 increased（ 2. 91-fold and4. 80-fold） but the level of MTS2823 decreased（ 0. 39-fold）. The expression of F6 did not change significantly in any group. Conclusion Streptomycin can either promote or suppress the expression of sRNA in M. tuberculosis,which indicates that sRNA of M. tuberculosis may be involved in the post-transcriptional regulation of drug stress responses,thus promoting or antagonizing the effect of streptomycin.更多还原