Details

Autor(en) / Beteiligte

• Galotto, Giulia
• Wisanpitayakorn, Pattipong
• Bibeau, Jeffrey P
• Liu, Yen-Chun
• Furt, Fabienne
• Pierce, Ellen C
• Simpson, Parker J
• Tüzel, Erkan
• Vidali, Luis

Titel

Myosin XI drives polarized growth by vesicle focusing and local enrichment of F-actin in Physcomitrium patens

Ist Teil von

• Plant physiology (Bethesda), 2021-12, Vol.187 (4), p.2509-2529

Ort / Verlag

United States: Oxford University Press

Erscheinungsjahr

2021

Quelle

MEDLINE

Beschreibungen/Notizen

• 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.