Premium
Salt‐stress signalling and the role of calcium in the regulation of the Arabidopsis ATHB7 gene
Author(s) -
HENRIKSSON E.,
NORDIN HENRIKSSON K.
Publication year - 2005
Publication title -
plant, cell and environment
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.646
H-Index - 200
eISSN - 1365-3040
pISSN - 0140-7791
DOI - 10.1111/j.1365-3040.2004.01263.x
Subject(s) - abscisic acid , homeobox , transcription factor , arabidopsis , microbiology and biotechnology , gene expression , signal transduction , gene , calcium , chemistry , calcium signaling , biology , biochemistry , organic chemistry , mutant
In plants changes in cytosolic calcium ion concentrations ([Ca 2+ ] cyt ) have been detected after various stress treatments, including salt treatment. The involvement of a Ca 2+ signal as an essential component of signalling pathways leading to downstream responses, such as gene expression, is supported only by a few studies. In this study the possible involvement of the salt stress‐induced increase in [Ca 2+ ] cyt in the signalling pathway leading to the induction of ATHB7 , a homeobox gene encoding a homeodomain leucine zipper (HDZip) transcription factor was analysed. The salt‐induced expression of ATHB7 was found to be independent of the Ca 2+ signal evoked by salt. Instead, it was found that ATHB7 expression in shoots was not dependent on a direct contact with salt or osmoticum, whereas in roots, ATHB7 seemed to be induced by the direct contact, indicating that signals from roots cause systemic induction of ATHB7 . Abscisic acid (ABA) or ABA‐dependent components were found to, at least partly, to function as the systemic signal.