IRK — Sorghum bicolor

Summary

SORBI_3007G044300 (SbIRK) on sorghum chromosome 7 encodes a nitrate transporter belonging to the PTR2 symporter and POT family, with annotated molecular functions including N-methylnicotinate, nicotinate, nitrate, fructose, and D-glucose transmembrane transporter activities, as well as zinc efflux permease, ubiquitin-like protein ligase, UDP-glucose 4-epimerase, RNA endonuclease, and transcription coactivator activities. The gene is associated with diverse biological processes such as N-methylnicotinate and fructose transport, glucose transmembrane transport, autophagy in response to ER stress, nitrogen utilization, zinc transport, root meristem specification, seed oilbody biogenesis, and trichome papilla formation. It localizes to the vacuolar membrane, Golgi trans cisterna, nuclear body, endosome, and mediator complex. SbIRK is linked to agronomic traits including seed protein content, oleic acid content, phosphorus uptake, nitrate transport, iron content and sensitivity, shoot elongation under submergence, branch angle, photoperiod-sensitive flowering time, lignin biosynthesis, and aphid response. Related genes in other species are associated with pre-mRNA maturation, nicotinate transport, and flowering time regulation.