STH — Daucus carota subsp. sativus

Summary

DcSTH (DCAR_028444) on carrot chromosome 8 encodes a B-box zinc finger protein with DNA-binding transcription factor activity, transcriptional co-regulator function, and ubiquitin ligase activity. It is associated with the regulation of photoperiodic flowering, including both upregulation of short-day flowering and downregulation of long-day flowering, as well as shade avoidance, anthocyanin and flavonoid metabolism, photomorphogenesis, circadian rhythm, and brassinosteroid signalling. The gene has been linked to root system morphology, light quality responses (blue, red, UV), seed set, yield, plant size, shoot elongation, nutrient responses (phosphorus, iron, cadmium), and stress tolerance. It localises to the nucleus and cytoplasmic complexes. Studies of related genes in other species connect the family to salt tolerance, flowering time, and gibberellin sensitivity.