Actin filament reorganisation controlled by the SCAR/WAVE complex mediates stomatal response to darkness.
New Phytol
; 215(3): 1059-1067, 2017 Aug.
Article
em En
| MEDLINE
| ID: mdl-28636198
ABSTRACT
Stomata respond to darkness by closing to prevent excessive water loss during the night. Although the reorganisation of actin filaments during stomatal closure is documented, the underlying mechanisms responsible for dark-induced cytoskeletal arrangement remain largely unknown. We used genetic, physiological and cell biological approaches to show that reorganisation of the actin cytoskeleton is required for dark-induced stomatal closure. The opal5 mutant does not close in response to darkness but exhibits wild-type (WT) behaviour when exposed to abscisic acid (ABA) or CaCl2 . The mutation was mapped to At5g18410, encoding the PIR/SRA1/KLK subunit of the ArabidopsisSCAR/WAVE complex. Stomata of an independent allele of the PIR gene (Atpir-1) showed reduced sensitivity to darkness and F1 progenies of the cross between opal5 and Atpir-1 displayed distorted leaf trichomes, suggesting that the two mutants are allelic. Darkness induced changes in the extent of actin filament bundling in WT. These were abolished in opal5. Disruption of filamentous actin using latrunculin B or cytochalasin D restored wild-type stomatal sensitivity to darkness in opal5. Our findings suggest that the stomatal response to darkness is mediated by reorganisation of guard cell actin filaments, a process that is finely tuned by the conserved SCAR/WAVE-Arp2/3 actin regulatory module.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Citoesqueleto de Actina
/
Arabidopsis
/
Proteínas de Arabidopsis
/
Escuridão
/
Complexos Multiproteicos
/
Estômatos de Plantas
/
Mutação
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
New Phytol
Assunto da revista:
BOTANICA
Ano de publicação:
2017
Tipo de documento:
Article
País de afiliação:
Reino Unido