Beyond Glycolysis: GAPDHs Are Multi-functional Enzymes Involved in Regulation of ROS, Autophagy, and Plant Immune Responses

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Plants can be infected by all pathogen classes, significantly impacting crop production and food security. Innate immune responses are critical to plant survival but must be tightly regulated in order to avoid negative impacts on growth and development. Here, we investigated the role of glyceraldehyde 3-phosphate dehydrogenase (GAPDH) proteins in the model plant Arabidopsis thaliana, a mustard relative. Animals have one GAPDH isoform, which has been intensely investigated and shown to exhibit diverse moonlighting, or non-traditional, activities. Plants possess multiple GAPDH isoforms that reside in distinct sub-cellular compartments. Using a combination of genetic investigation of specific GAPDH knockouts coupled with microscopy, we found that GAPDHs regulate accumulation of reactive oxygen species and cell death in response to inoculation with the bacterial pathogen Pseudomonas syringae. The GAPC1 isoform exhibits diverse sub-cellular localizations and dynamically responds to perception of bacterial flagellin. The GAPC1 and GAPA1 isoforms also negatively regulate autophagy, which is an important component of plant immune responses. Taken together, our results demonstrate that multiple GAPDH isoforms act to negatively regulate plant defense responses. Negative regulators are important for precisely regulating the duration and amplitude of immune responses.

Vyšlo v časopise: Beyond Glycolysis: GAPDHs Are Multi-functional Enzymes Involved in Regulation of ROS, Autophagy, and Plant Immune Responses. PLoS Genet 11(4): e32767. doi:10.1371/journal.pgen.1005199
Kategorie: Research Article
prolekare.web.journal.doi_sk: https://doi.org/10.1371/journal.pgen.1005199

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