mRNA degradation in Mycobacterium tuberculosis with DosR ectopically induced. Mycobacterium tuberculosis H37Rv

After induction of DosR from a tet regulated promoter (uninduced controls were treated with an equivalent ammount of the solvent, DMSO), transcription was arrested using 50 ug/ul of rifampin leaving RNA degradation as the sole vector responsible for mRNA abundance. mRNA half-lives were calculated from the decay of signal intensity from T0. Overall design: Three replicates for each condition (DosR induced and uninduced) were sampled after 0, 10, 20, 30, and 60 minutes of mRNA decay for a total of 30 arrays.

从四环素调控启动子（tet regulated promoter）诱导DosR表达，未诱导对照组使用等量溶剂二甲基亚砜（DMSO）处理。随后采用50 μg/μL的利福平（rifampin）阻断转录，此时RNA降解成为决定信使RNA（mRNA）丰度的唯一因素。基于T0时刻的信号强度衰减计算mRNA的半衰期。实验总体设计：每个实验条件（DosR诱导组与未诱导组）各设置3次生物学重复，分别在mRNA降解0、10、20、30和60分钟时取样，共计30张微阵列芯片（arrays）。