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
The synthesis and structural analysis of a quintuple [6]helicene with a corannulene core is reported. The compound was synthesized from corannulene in three steps including a five‐fold intramolecular direct arylation. X‐ray crystallographic analysis revealed a
- PAR ID:
- 10235940
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 57
- Issue:
- 5
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 1337-1341
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Summary cpk quintuple mutants and analyzed stomatal movements in response to CO2, light and abscisic acid (ABA). Interestingly, we found thatcpk3/5/6/11/23 quintuple mutant plants, but not other analyzedcpk quadruple/quintuple mutants, were defective in high CO2‐induced stomatal closure and, unexpectedly, also in low CO2‐induced stomatal opening. Furthermore, K+‐uptake‐channel activities were reduced incpk3/5/6/11/23 quintuple mutants, in correlation with the stomatal opening phenotype. However, light‐mediated stomatal opening remained unaffected, and ABA responses showed slowing in some experiments. By contrast, CO2‐regulated stomatal movement kinetics were not clearly affected in plasma membrane‐targetedcbl1/4/5/8/9 quintuple mutant plants.cpk mutants that function in CO2control of stomatal movements and support the results of classical studies showing a role for Ca2+in this response. -
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