The microtubule-associated protein WDL4 modulates auxin distribution to promote apical hook opening in Arabidopsis.
Plant Cell
; 33(6): 1927-1944, 2021 07 19.
Article
en En
| MEDLINE
| ID: mdl-33730147
ABSTRACT
The unique apical hook in dicotyledonous plants protects the shoot apical meristem and cotyledons when seedlings emerge through the soil. Its formation involves differential cell growth under the coordinated control of plant hormones, especially ethylene and auxin. Microtubules are essential players in plant cell growth that are regulated by multiple microtubule-associated proteins (MAPs). However, the role and underlying mechanisms of MAP-microtubule modules in differential cell growth are poorly understood. In this study, we found that the previously uncharacterized Arabidopsis MAP WAVE-DAMPENED2-LIKE4 (WDL4) protein plays a positive role in apical hook opening. WDL4 exhibits a temporal expression pattern during hook development in dark-grown seedlings that is directly regulated by ethylene signaling. WDL4 mutants showed a delayed hook opening phenotype while overexpression of WDL4 resulted in enhanced hook opening. In particular, wdl4-1 mutants exhibited stronger auxin accumulation in the concave side of the apical hook. Furthermore, the regulation of the auxin maxima and trafficking of the auxin efflux carriers PIN-FORMED1 (PIN1) and PIN7 in the hook region is critical for WDL4-mediated hook opening. Together, our study demonstrates that WDL4 positively regulates apical hook opening by modulating auxin distribution, thus unraveling a mechanism for MAP-mediated differential plant cell growth.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Arabidopsis
/
Proteínas de Arabidopsis
/
Ácidos Indolacéticos
/
Proteínas Asociadas a Microtúbulos
Tipo de estudio:
Risk_factors_studies
Idioma:
En
Revista:
Plant Cell
Asunto de la revista:
BOTANICA
Año:
2021
Tipo del documento:
Article
País de afiliación:
China