PI — Lactuca sativa

Summary

LsPI (also known as PI or GLO) on chromosome 1 of garden lettuce encodes a protein with MADS-box and K-box domains, and is associated with DNA-binding and transcription regulatory activity. The gene is associated with the specification of floral organ identity, including petal and stamen identity, as well as the maintenance of floral meristem identity and floral organ number. It has been linked to numerous floral traits such as petal number, stamen morphology, carpel shape, and flower development, along with agronomically relevant traits including plant male sterility, seed longevity, photoperiod-sensitive flowering time, bacterial blight disease resistance, and photosynthetic rate. The gene is also linked to responses to heat stress, chitin, and bacterial molecules, and localizes to the nucleus, plastid, and plasmodesmata. Studies of related genes in other species link the family to petal and stamen formation and floral organ development.