miR-25

Although autophagy is an important regulatory pathway to eliminate intracellular Mtb, the effect of NPC1 during Mtb infection remains largely unclear. Here, we found that microRNA-25 (miR-25) expression was significantly upregulated during in the lung tissues of mice infected with Bacillus Calmette-Guerin (BCG) and macrophages infected with Mtb or BCG, especially in the early stages of infection.

We validated that miR-25 targets the NPC1 protein located on the lysosomal membrane, resulting in damage to lysosomal function, thereby inhibiting autophagolysosome formation and promoting the survival of Mtb and BCG. Consistently, mice lacking miR-25 exhibited more resistant to BCG infection. In addition, we found that Rv1759c induces the expression of miR-25 through NFKB inhibitor zeta (NFKBIZ).