SPS — Nicotiana attenuata

Summary

A4A49_05615 (SPS, also known as PMT1) in coyote tobacco (Nicotiana attenuata) encodes a protein with putrescine N-methyltransferase, spermidine synthase, spermine synthase, and S-adenosylmethionine-dependent tRNA methyltransferase activities, and belongs to the spermidine synthase and SAM-dependent methyltransferase superfamilies. It is associated with polyamine, nicotine, sucrose, and UDP anabolism, phloem loading, primary growth, response to herbivores and insects, detoxification, starch breakdown, and virus-induced PTGS. The gene product localizes to the cytosol, nucleus, mitochondria, and plasma membrane. It is linked to traits including starch mobilization, sucrose and starch content, photosynthetic rate, respiration rate, jasmonic acid content, high temperature stress response, disease tolerance, and salt tolerance. Studies of related genes in other species connect the family to fruit sweetness, chilling stress response, and saline-alkali tolerance.