HEL — Brassica oleracea var. botrytis

Summary

BoHEL (HEL, PR4) on cauliflower chromosome 3 encodes a PR4 family protein containing a Barwin domain and a RlpA-like superfamily domain. The product exhibits RNA nuclease, hydrolase, transmembrane receptor protein serine/threonine kinase, chitin-binding, sugar-binding, and protein-binding activities. BoHEL is associated with defence responses to bacteria, fungi, viruses, and herbivores, as well as systemic acquired resistance, immune response, and hypersensitive response-programmed cell death. It is linked to ethylene, auxin, and brassinosteroid signalling, phloem transport, leaf vascular tissue pattern formation, and leaf vein morphology. The gene is associated with drought and salt tolerance, disease resistance, resistance to Botrytis cinerea, and abnormal leaf venation with reduced vein number. The protein localises to secretory vesicles, the extracellular region, and the plasma membrane. Studies of related genes in other species link the family to seed germination under salt stress and insect resistance.