Myosin XI drives polarized growth by vesicle focusing and local enrichment of F-actin in Physcomitrium patens.
Plant Physiol
; 187(4): 2509-2529, 2021 12 04.
Article
em En
| MEDLINE
| ID: mdl-34890463
ABSTRACT
In tip-growing plant cells, growth results from myosin XI and F-actin-mediated deposition of cell wall polysaccharides contained in secretory vesicles. Previous evidence showed that myosin XI anticipates F-actin accumulation at the cell's tip, suggesting a mechanism where vesicle clustering via myosin XI increases F-actin polymerization. To evaluate this model, we used a conditional loss-of-function strategy by generating moss (Physcomitrium patens) plants harboring a myosin XI temperature-sensitive allele. We found that loss of myosin XI function alters tip cell morphology, vacuolar homeostasis, and cell viability but not following F-actin depolymerization. Importantly, our conditional loss-of-function analysis shows that myosin XI focuses and directs vesicles at the tip of the cell, which induces formin-dependent F-actin polymerization, increasing F-actin's local concentration. Our findings support the role of myosin XI in vesicle focusing, possibly via clustering and F-actin organization, necessary for tip growth, and deepen our understanding of additional myosin XI functions.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Plantas
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Actinas
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Miosinas
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Bryopsida
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Plant Physiol
Ano de publicação:
2021
Tipo de documento:
Article
País de afiliação:
Estados Unidos
País de publicação:
EEUU
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ESTADOS UNIDOS
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ESTADOS UNIDOS DA AMERICA
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EUA
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UNITED STATES
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UNITED STATES OF AMERICA
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US
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USA