P5CS — Hordeum vulgare subsp. vulgare

Summary

HORVU.MOREX.R3.1HG0073870 (HvP5CS) on barley chromosome 1H encodes a bifunctional enzyme with glutamate 5-kinase (EC 2.7.2.11) and glutamylphosphate reductase (EC 1.2.1.41) activities, catalysing the first two steps of proline biosynthesis. The gene is associated with proline metabolism, including both biosynthesis and breakdown, and with responses to desiccation, hyperosmotic salinity, oxidative stress, and stomatal closure. It has been linked to agronomic traits such as grain yield, grain filling period, plant height, rooting depth, lateral root length, net photosynthetic rate, and salinity tolerance. Associations also include embryo development, leaf senescence, flowering time, and the ascorbate-glutathione cycle. Studies of related genes in other species connect the family to drought, salt, and osmotic stress tolerance, as well as pollen development and root elongation under low water potential.