Negative Immune Regulator CAD7 Functions as a Small-Molecule Aldehyde Reductase and Increases Histamine Accumulation in Arabidopsis.

ABSTRACT: Negative immune regulator CAD7 is a non-canonical member of the CAD (cinnamyl alcohol dehydrogenase) family in plants. However, little is known on its biochemical functions and underlying mechanisms of immune regulation. Here, we show that Arabidopsis thaliana AtCAD7 harbours substrate-binding residues divergent from lignin-forming CADs (AtCAD4/5), being conserved with bacterial alcohol dehydrogenases EcYahK and EcYjgB. Comparative enzymatic analysis revealed that AtCAD7 exhibits a broad substrate preference for diverse small-molecule aldehydes, including histamine-derived intermediates, being distinct from the canonical lignin-forming AtCAD5. Metabolomic analyses revealed that AtCAD7-overexpression transformants were affected in the biosynthesis and metabolism of amino acids, whereas AtCA

SUBMITTER: Ding L 

PROVIDER: S-EPMC12744961 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature