title: HbCIPK2, a novel CBL-interacting protein kinase from halophyte Hordeum brevisubulatum, confers salt and osmotic stress tolerance.
abstract: Protein kinases play an important role in regulating the response to abiotic stress in plant. CIPKs are plant-specific signal transducers, and some members have been identified. However, the precise functions of novel CIPKs still remain unknown. Here we report that HbCIPK2 is a positive regulator of salt and osmotic stress tolerance. HbCIPK2 was screened out of the differentially expressed fragments from halophyte Hordeum brevisubulatum by cDNA-AFLP technique, and was a single-copy gene without intron. Expression of HbCIPK2 was increased by salt, drought and ABA treatment. HbCIPK2 is mainly localized to the plasma membrane and nucleus. Ectopic expression of 35S:HbCIPK2 not only rescued the salt hypersensitivity in Arabidopsis mutant sos2-1, but also enhanced salt tolerance in Arabidopsis wild type, and exhibited tolerance to osmotic stress during germination. The HbCIPK2 contributed to the ability to prevent K(+) loss in root and to accumulate less Na(+) in shoot resulting in K(+) /Na(+) homeostasis and protection of root cell from death, which is consistent with the gene expression profile of HbCIPK2-overexpressing lines. These findings imply possible novel HbCIPK2-mediated salt signalling pathways or networks in H. brevisubulatum.
authors.affiliation: Beijing Agro-biotechnology Research Center, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China.
authors.forename: Ruifen
authors.initials: R
authors.lastname: Li
authors.forename: Junwen
authors.initials: J
authors.lastname: Zhang
authors.forename: Guangyu
authors.initials: G
authors.lastname: Wu
authors.forename: Hongzhi
authors.initials: H
authors.lastname: Wang
authors.forename: Yajuan
authors.initials: Y
authors.lastname: Chen
authors.forename: Jianhua
authors.initials: J
authors.lastname: Wei
mesh_terms: D000595:Amino Acid Sequence; D054458:Amplified Fragment Length Polymorphism Analysis; D017360:Arabidopsis / Q000235:genetics / Q000502:physiology; D029681:Arabidopsis Proteins / Q000378:metabolism; D019610:Cytoprotection / Q000187:drug effects; D018076:DNA, Complementary / Q000235:genetics; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D001467:Hordeum / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics / Q000502:physiology*; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D009997:Osmotic Pressure / Q000187:drug effects; D010802:Phylogeny; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D018517:Plant Roots / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D011188:Potassium / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D011522:Protons; D055049:Salt Tolerance / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D055051:Salt-Tolerant Plants / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics / Q000502:physiology*; D016415:Sequence Alignment; D012964:Sodium / Q000378:metabolism; D012965:Sodium Chloride / Q000494:pharmacology; D013312:Stress, Physiological / Q000187:drug effects / Q000235:genetics; D013347:Subcellular Fractions / Q000187:drug effects / Q000201:enzymology
chemical_list: D029681:Arabidopsis Proteins; D018076:DNA, Complementary; D010940:Plant Proteins; D011522:Protons; D012965:Sodium Chloride; D012964:Sodium; C406738:SOS2 protein, Arabidopsis; D017346:Protein Serine-Threonine Kinases; D011188:Potassium