HMA2 — Brassica oleracea

Summary

BoHMA2, located on chromosome 7 of cabbage (Brassica oleracea), encodes a P-type ATPase of the IB subfamily, a cation transporter with heavy-metal-associated domains. The product exhibits P-type divalent copper, monovalent copper, zinc, and calcium transporter activities, as well as cadmium-exporting ATPase and proton-transporting ATPase activities, and binds copper, calmodulin, and ATP. It is associated with detoxification of copper ions, copper and zinc ion homeostasis, proton export across the plasma membrane, cell pH regulation, and response to toxic substances. Localised to the vacuolar, Golgi, and plasma membranes, BoHMA2 is associated with photosynthetic rate, chlorophyll content, root length, and with cadmium tolerance, translocation, and accumulation, zinc partitioning and transport, metal homeostasis, and fungal resistance. Studies of related genes in other species connect the family to cadmium xylem loading and long-distance translocation, as well as zinc homeostasis.