Figure 7.

Mycobacterial mechanism of MAPK pathway control during C. elegans infection. (A) When C. elegans is infected with mycobacteria, the p38 MAPK pathway (PMK‐1) is activated, leading to an innate immune response through downstream regulators, including the NRF‐like regulator SKN‐1, that increase pathogen resistance. The MAPK phosphatase, VHP‐1, inhibits activation of MAPK, but is inactivated when foreign organisms are recognized, allowing MAPK‐mediated protection. (B) In contrast to nonpathogenic mycobacteria (M. smegmatis), pathogenic mycobacteria (M. marinum) may inhibit activation of MAPK through the MAPK phosphatase VHP‐1, allowing colonization and pathogenesis.