title: Regulation of the major vacuolar Ca²⁺ transporter genes, by intercellular Ca²⁺ concentration and abiotic stresses, in tip-burn resistant Brassica oleracea.
abstract: Calcium is an essential plant macronutrient that has unique structural and signaling roles related to tip-burn disorder in Brassica spp. crops. For two types of cabbage inbred lines, tip-burn susceptible and resistant, we measured and compared major macronutrient cations, including Ca(2+), in leaves. In both lines, Ca(2+), Mg(2+), Na(+), and K(+), accumulated more in leaf base than in leaf apex. Ca(2+) and K(+) were >2 times more abundant in the tip-burn resistant line, while Na(+) was higher in the susceptible line. Ca(2+) differences between the two lines resulted from differential accumulation of calcium into cell vacuoles. We profiled major vacuolar Ca(2+) transporters, in both cabbage lines, by growth time and intercellular Ca(2+) concentration. Expression pattern of several Ca(2+) transporter genes differed between tip-burn susceptible and resistant lines by growth time points. We also identified promoter regions of the major Ca(2+) vacuole transporter genes, CAX1, ACA4, and ACA11, which displayed hormonal, light and defense-related cis-acting regulatory elements. Finally, transporter genes in the two cabbage lines responded differently to abiotic stresses, demonstrating diversity in gene regulation among orthologous genes.
authors.affiliation: Green Bio Research Center, Cabbage Genomics Assisted Breeding Supporting Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Gwahangno 111, Daejeon 305-806, South Korea.
authors.forename: Jeongyeo
authors.initials: J
authors.lastname: Lee
authors.forename: Inkyu
authors.initials: I
authors.lastname: Park
authors.forename: Zee-Won
authors.initials: ZW
authors.lastname: Lee
authors.forename: Suk Weon
authors.initials: SW
authors.lastname: Kim
authors.forename: Namkwon
authors.initials: N
authors.lastname: Baek
authors.forename: Hong-Seok
authors.initials: HS
authors.lastname: Park
authors.forename: Sang Un
authors.initials: SU
authors.lastname: Park
authors.forename: Seokyoon
authors.initials: S
authors.lastname: Kwon
authors.forename: Hyeran
authors.initials: H
authors.lastname: Kim
mesh_terms: D001937:Brassica / Q000235:genetics* / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism*; D000252:Calcium-Transporting ATPases / Q000235:genetics*; D002412:Cations / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics*; D013312:Stress, Physiological; D014617:Vacuoles / Q000378:metabolism*
chemical_list: D002412:Cations; D010940:Plant Proteins; D000252:Calcium-Transporting ATPases; D002118:Calcium