Role of Proton Motive Force in Photoinduction of Cytoplasmic Streaming in Vallisneria Mesophyll Cells.
Plants (Basel)
; 9(3)2020 Mar 18.
Article
en En
| MEDLINE
| ID: mdl-32197471
In mesophyll cells of the aquatic monocot Vallisneria, red light induces rotational cytoplasmic streaming, which is regulated by the cytoplasmic concentration of Ca2+. Our previous investigations revealed that red light induces Ca2+ efflux across the plasma membrane (PM), and that both the red light-induced cytoplasmic streaming and the Ca2+ efflux are sensitive to vanadate, an inhibitor of P-type ATPases. In this study, pharmacological experiments suggested the involvement of PM H+-ATPase, one of the P-type ATPases, in the photoinduction of cytoplasmic streaming. We hypothesized that red light would activate PM H+-ATPase to generate a large H+ motive force (PMF) in a photosynthesis-dependent manner. We demonstrated that indeed, photosynthesis increased the PMF and induced phosphorylation of the penultimate residue, threonine, of PM H+-ATPase, which is a major activation mechanism of H+-ATPase. The results suggested that a large PMF generated by PM H+-ATPase energizes the Ca2+ efflux across the PM. As expected, we detected a putative Ca2+/H+ exchange activity in PM vesicles isolated from Vallisneria leaves.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Idioma:
En
Revista:
Plants (Basel)
Año:
2020
Tipo del documento:
Article
País de afiliación:
Japón
Pais de publicación:
Suiza