DM1 — Lactuca sativa

Summary

LsDM1 (DM1, also known as SGR1, SGR2, NYE1, NYE2) on chromosome 3 of garden lettuce (Lactuca sativa) encodes a Staygreen domain-containing protein with multiple annotated enzymatic activities, including 7-hydroxymethyl chlorophyll A reductase, pheophytinase, and chlorophyll b reductase activities. The gene is associated with chlorophyll metabolism, particularly chlorophyll breakdown and its regulation, as well as the chlorophyll cycle, polyamine breakdown, and the catabolic process of PSII-associated light-harvesting complex II. It is linked to leaf senescence, leaf yellowing tolerance, chlorophyll content, and yield traits, along with responses to drought, salt, and abscisic acid. Localization evidence places the product at the chloroplast thylakoid membrane and plastid envelope. Studies of related genes in other species link the family to stay-green phenotypes, cell death regulation, and disease resistance.