Cyclic-nucleotide- and Ca2+/calmodulin-regulated channels in plants: targets for manipulating heavy-metal tolerance, and possible physiological roles

Citation
T. Arazi et al., Cyclic-nucleotide- and Ca2+/calmodulin-regulated channels in plants: targets for manipulating heavy-metal tolerance, and possible physiological roles, BIOCH SOC T, 28, 2000, pp. 471-475
Citations number
27
Categorie Soggetti
Biochemistry & Biophysics
Journal title
BIOCHEMICAL SOCIETY TRANSACTIONS
ISSN journal
03005127 → ACNP
Volume
28
Year of publication
2000
Part
4
Pages
471 - 475
Database
ISI
SICI code
0300-5127(200008)28:<471:CACCIP>2.0.ZU;2-4
Abstract
Recently we discovered a tobacco protein (designated NtCBP4) that modulates heavy-metal tolerance in transgenic plants. Structurally, NtCBP4 is simila r to mammalian cyclic-nucleotide-gated non-selective cation channels contai ning six putative transmembrane domains, a predicted pore region, a conserv ed cyclic-nucleotide-binding domain, and a high-affinity calmodulin-binding site that coincides with its cyclic-nucleotide-binding domain. Transgenic tobacco expressing the plasma-membrane-localized NtCBP4 exhibit improved to lerance to Ni2+ and hypersensitivity to Pb2+, which are associated with a d ecreased accumulation of Ni2+ and a enhanced accumulation of Pb2+ respectiv ely. Transgenic plants expressing a truncated version of NtCBP4, from which regulatory domains had been removed, have a different phenotype. Here we d escribe our approach to studying the involvement of NtCBP4 in heavy-metal t olerance and to elucidate its physiological role.