Guard cell ABA and CO2 signaling network updates and Ca2+ sensor priming hypothesis.
Stomatal pores in the epidermis of plants enable gas exchange between plants and the atmosphere, a process vital to plant life. Pairs of specialized guard cells surround and control stomatal apertures. Stomatal closing is induced by abscisic acid (ABA) and elevated CO(2) concentrations. Recent advances have been made in understanding ABA signaling and in characterizing CO(2) transduction mechanisms and CO(2) signaling mutants. In addition, models of Ca(2+)-dependent and Ca(2+)-independent signaling in guard cells have been developed and a new hypothesis has been formed in which physiological stimuli are proposed to prime Ca(2+) sensors, thus enabling specificity in Ca(2+)-dependent signal transduction.
Israelsson
Maria
M
Division of Biological Sciences, Cell and Developmental Biology Section, and Center for Molecular Genetics 0116, University of California, San Diego, La Jolla, California 92093-0116, USA.
Siegel
Robert S
RS
Young
Jared
J
Hashimoto
Mimi
M
Iba
Koh
K
Schroeder
Julian I
JI
D000040:Abscisic Acid / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism*; D002245:Carbon Dioxide / Q000378:metabolism*; D018515:Plant Leaves / Q000166:cytology* / Q000378:metabolism; D015398:Signal Transduction
D002245:Carbon Dioxide; D000040:Abscisic Acid; D002118:Calcium