TMT — Lactuca sativa

Summary

LsTMT, encoded by the garden lettuce gene LSAT_V11C200088770 on chromosome 2, is a SAM-dependent methyltransferase belonging to the gamma-tocopherol methyltransferase (γ-TMT) family. The enzyme exhibits tocopherol C-methyltransferase and N-methyltransferase activities. In lettuce, LsTMT is associated with vitamin E and alkaloid biosynthesis, particularly vindoline anabolism, and localises to multiple cellular compartments including the vacuolar membrane, chloroplast inner membrane, thylakoid, cytosol and nucleus. The gene has been linked to alpha-tocopherol biosynthesis, salt stress tolerance, resistance to Botrytis cinerea, cold adaptation, oxidative stress tolerance, and seed yield. Studies of related genes in other species connect the family to tocochromanol biosynthesis, plant development, and chlorophyll content, and to vitamin E and alpha-tocopherol accumulation.