Drought stress is one of the most destructive environmental factors that
affect plant growth and production. Mitogen-activated protein kinase (MAPK)
are important signaling pathways that are involved in both biotic and
abiotic stresses. Liu Wang and his colleagues from China Agricultural
University studied SlMAPK1 and its role in tomato.

The team developed transgenic tomato plants overexpressing SlMAPK1 to
investigate the role it plays in drought tolerance. Compared with wildtype
plants, the SlMAPK1-overexpressing lines exhibited less wilting and less
cell membrane damage. The transgenic plants also accumulated less hydrogen
peroxide, showed higher activities of antioxidant enzymes, and had an
elevated expression of stress-related genes.

These results suggest that SlMAPK1 plays a positive role in plant response
to drought stress by activating antioxidant enzymes, and controlling the
expression of stress-related genes.

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