MS1 — Lactuca sativa

Summary

LsMS1 (MS1) on lettuce chromosome 2 encodes a cobalamin-independent methionine synthase, also annotated with ADP-glucose pyrophosphatase, ADP-ribose pyrophosphatase, nucleoside diphosphatase, and NAD+ diphosphatase activities, as well as DNA binding transcription factor activity. The gene is associated with de novo L-methionine biosynthesis, regulation of starch biosynthesis, DNA methylation-dependent heterochromatin assembly, and indole glucosinolate biosynthesis. It is linked to defense responses including callose deposition, induced systemic resistance, response to insects, and innate immune signaling, as well as responses to ozone, oxidative stress, hypoxia, and bacteria. Associations with whole plant size, seed development, root morphology, salt tolerance, and male sterility have been noted. The protein localizes to chloroplasts, mitochondria, cytosol, plasmodesmata, and the apoplast. Studies of related genes in other species link the family to methionine levels, pollen development, seed germination, and pathogen resistance.