Mycobacterium tuberculosis induces the miR-33 locus to reprogram autophagy and host lipid metabolism

M Ouimet, S Koster, E Sakowski, B Ramkhelawon… - Nature …, 2016 - nature.com
M Ouimet, S Koster, E Sakowski, B Ramkhelawon, C Van Solingen, S Oldebeken…
Nature immunology, 2016nature.com
Mycobacterium tuberculosis (Mtb) survives in macrophages by evading delivery to the
lysosome and promoting the accumulation of lipid bodies, which serve as a bacterial source
of nutrients. We found that by inducing the microRNA (miRNA) miR-33 and its passenger
strand miR-33*, Mtb inhibited integrated pathways involved in autophagy, lysosomal
function and fatty acid oxidation to support bacterial replication. Silencing of miR-33 and miR-
33* by genetic or pharmacological means promoted autophagy flux through derepression of …
Abstract
Mycobacterium tuberculosis (Mtb) survives in macrophages by evading delivery to the lysosome and promoting the accumulation of lipid bodies, which serve as a bacterial source of nutrients. We found that by inducing the microRNA (miRNA) miR-33 and its passenger strand miR-33*, Mtb inhibited integrated pathways involved in autophagy, lysosomal function and fatty acid oxidation to support bacterial replication. Silencing of miR-33 and miR-33* by genetic or pharmacological means promoted autophagy flux through derepression of key autophagy effectors (such as ATG5, ATG12, LC3B and LAMP1) and AMPK-dependent activation of the transcription factors FOXO3 and TFEB, which enhanced lipid catabolism and Mtb xenophagy. These data define a mammalian miRNA circuit used by Mtb to coordinately inhibit autophagy and reprogram host lipid metabolism to enable intracellular survival and persistence in the host.
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