Home > Research > Publications & Outputs > The role of calcium in ABA-induced gene express...
View graph of relations

The role of calcium in ABA-induced gene expression and stomatal movements.

Research output: Contribution to journalJournal articlepeer-review

  • Alex A. R. Webb
  • Mark G. Larman
  • Lucy T. Montgomery
  • Jane E. Taylor
  • Alistair M. Hetherington
<mark>Journal publication date</mark>05/2001
<mark>Journal</mark>Plant Journal
Issue number3
Number of pages12
Pages (from-to)351-362
Publication StatusPublished
<mark>Original language</mark>English


There is much interest in the transduction pathways by which abscisic acid (ABA) regulates stomatal movements (ABA-turgor signalling) and by which this phytohormone regulates the pattern of gene expression in plant cells (ABA-nuclear signalling). A number of second messengers have been identified in both the ABA-turgor and ABA-nuclear signalling pathways. A major challenge is to understand the architecture of ABA-signalling pathways and to determine how the ABA signal is coupled to the appropriate response. We have investigated whether separate Ca2+-dependent and -independent ABA-signalling pathways are present in guard cells. Our data suggest that increases in [Ca2+]i are a common component of the guard cell ABA-turgor and ABA-nuclear signalling pathways. The effects of Ca2+ antagonists on ABA-induced stomatal closure and the ABA-responsive CDeT6-19 gene promoter suggest that Ca2+ is involved in both ABA-turgor signalling and ABA-nuclear signalling in guard cells. However, the sensitivity of these pathways to alterations in the external calcium concentration differ, suggesting that the ABA-nuclear and ABA-turgor signalling pathways are not completely convergent. Our data suggest that whilst Ca2+-independent signalling elements are present in the guard cell, they do not form a completely separate Ca2+-independent ABA-signalling pathway.