CIPK6, a CBL-interacting protein kinase is required for development and salt tolerance in plants

Plant J. 2009 Jun;58(5):778-90. doi: 10.1111/j.1365-313X.2009.03812.x. Epub 2009 Feb 2.

Abstract

Calcineurin B-like proteins (CBL) and CBL-interacting protein kinases (CIPK) mediate plant responses to a variety of external stresses. Here we report that Arabidopsis CIPK6 is also required for the growth and development of plants. Phenotype of tobacco plants ectopically expressing a homologous gene (CaCIPK6) from the leguminous plant chickpea (Cicer arietinum) indicated its functional conservation. A lesion inAtCIPK6 significantly reduced shoot-to-root and root basipetal auxin transport, and the plants exhibited developmental defects such as fused cotyledons, swollen hypocotyls and compromised lateral root formation, in conjunction with reduced expression of a number of genes involved in auxin transport and abiotic stress response. The Arabidopsis mutant was more sensitive to salt stress compared to wild-type, while overexpression of a constitutively active mutant of CaCIPK6 promoted salt tolerance in transgenic tobacco. Furthermore, tobacco seedlings expressing the constitutively active mutant of CaCIPK6 showed a developed root system, increased basipetal auxin transport and hypersensitivity to auxin. Our results provide evidence for involvement of a CIPK in auxin transport and consequently in root development, as well as in the salt-stress response, by regulating the expression of genes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Arabidopsis / enzymology
  • Arabidopsis / genetics*
  • Arabidopsis / growth & development
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / metabolism*
  • Cloning, Molecular
  • Gene Expression Regulation, Developmental
  • Gene Expression Regulation, Plant
  • Indoleacetic Acids / metabolism
  • Molecular Sequence Data
  • Mutagenesis, Insertional
  • Nicotiana / enzymology
  • Nicotiana / genetics
  • Nicotiana / metabolism
  • Plants, Genetically Modified / enzymology
  • Plants, Genetically Modified / genetics
  • Plants, Genetically Modified / growth & development
  • Protein Kinases / genetics
  • Protein Kinases / metabolism*
  • Salt Tolerance / genetics*
  • Sequence Alignment
  • Stress, Physiological

Substances

  • Arabidopsis Proteins
  • Indoleacetic Acids
  • CIPK6 protein, Arabidopsis
  • Protein Kinases