Little is known about long‐distance mesophyll‐driven signals that regulate stomatal conductance. Soluble and/or vapor‐phase molecules have been proposed. In this study, the involvement of the gaseous signal ethylene in the modulation of stomatal conductance in We present a diffusion model which indicates that gaseous signaling molecule/s with a shorter/direct diffusion pathway to guard cells are more probable for rapid mesophyll‐dependent stomatal conductance changes. We, therefore, analyzed different Arabidopsis ethylene‐signaling and biosynthesis mutants for their ethylene production and kinetics of stomatal responses to ABA/[CO2]‐shifts. According to our research, higher [CO2] causes Arabidopsis rosettes to produce more ethylene. An ACC‐synthase octuple mutant with reduced ethylene biosynthesis exhibits dysfunctional CO2‐induced stomatal movements. Ethylene‐insensitive receptor (gain‐of‐function), These findings suggest essential functions of ethylene biosynthesis and signaling components in tuning/accelerating stomatal conductance responses to CO2and ABA.
Low concentrations of CO2cause stomatal opening, whereas [CO2] elevation leads to stomatal closure. Classical studies have suggested a role for Ca2+and protein phosphorylation in CO2‐induced stomatal closing. Calcium‐dependent protein kinases (CPKs) and calcineurin‐B‐like proteins (CBLs) can sense and translate cytosolic elevation of the second messenger Ca2+into specific phosphorylation events. However, Ca2+‐binding proteins that function in the stomatal CO2response remain unknown. Time‐resolved stomatal conductance measurements using intact plants, and guard cell patch‐clamp experiments were performed. We isolated Our findings describe combinatorial
- Award ID(s):
- 1900567
- NSF-PAR ID:
- 10398543
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- New Phytologist
- Volume:
- 229
- Issue:
- 5
- ISSN:
- 0028-646X
- Page Range / eLocation ID:
- p. 2765-2779
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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