PPX — Zea mays

Summary

ZmPPX (ZM00001EB332380) on maize chromosome 8 encodes an oxygen-dependent protoporphyrinogen oxidase (EC 1.3.3.4), a FAD/NAD-binding oxidoreductase with amine oxidase and zeta-carotene desaturase domains that binds cobalt ions and FAD. The gene is associated with pigment accumulation, endosperm development, and chloroplast RNA modification. It has been linked to chlorophyll content, rubisco content, total soluble sugar and starch content, phosphorus uptake, drought tolerance, stripe rust, plant height, leaf dry weight, germination rate, and root morphology traits. Associations with embryo viability, seed set, pollen development, female gametogenesis, seedling growth, reactive oxygen species accumulation, and cell death have been reported. The product localises to plastid thylakoid and chloroplast membranes, mitochondria, and the ER. Studies of related genes in other species link the family to herbicide resistance and grain flour browning.