Mycobacterium marinum induces a marked LC3 recruitment to its containing phagosome that depends on a functional ESX-1 secretion system
Article first published online: 30 MAR 2011
© 2011 Blackwell Publishing Ltd
Volume 13, Issue 6, pages 814–835, June 2011
How to Cite
Lerena, M. C. and Colombo, M. I. (2011), Mycobacterium marinum induces a marked LC3 recruitment to its containing phagosome that depends on a functional ESX-1 secretion system. Cellular Microbiology, 13: 814–835. doi: 10.1111/j.1462-5822.2011.01581.x
- Issue published online: 16 MAY 2011
- Article first published online: 30 MAR 2011
- Accepted manuscript online: 21 MAR 2011 01:21PM EST
- Received 22 September, 2010; revised 3 January, 2011; accepted 19 January, 2011.
Autophagy has been implicated as part of the innate immune system against different intracellular microorganisms. Mycobacterium marinum is the causative agent of the fish-tank granuloma and has been widely used as an alternative model to study pathogenic mycobacteria. In this report, we show an active interaction of M. marinum with the autophagic protein LC3, an event that requires pathogen viability and bacterial protein synthesis. Interestingly, M. marinum lacking the region of difference 1 (RD1) is unable to recruit LC3, indicating that a functional ESX-1 secretion system is an absolute requirement for this process. In addition, phagocytosis of the bacteria is also a condition for the LC3 rearrangement induced by M. marinum. We present evidence that this pathogen resides temporarily in a LC3-decorated compartment with late endocytic features but mostly devoid of lysosomal enzymes or degradative properties. In addition our results indicate that autophagy induction by rapamycin treatment leads to maturation of the M. marinum-containing compartment.