Unusual Roles of Secretory SNARE SYP132 in Plasma Membrane H+-ATPase Traffic and Vegetative Plant Growth.
Plant Physiol
; 180(2): 837-858, 2019 06.
Article
in En
| MEDLINE
| ID: mdl-30926657
ABSTRACT
The plasma membrane proton (H+)-ATPases of plants generate steep electrochemical gradients and activate osmotic solute uptake. H+-ATPase-mediated proton pumping orchestrates cellular homeostasis and is a prerequisite for plastic cell expansion and plant growth. All evidence suggests that the population of H+-ATPase proteins at the plasma membrane reflects a balance of their roles in exocytosis, endocytosis, and recycling. Auxin governs both traffic and activation of the plasma membrane H+-ATPase proteins already present at the membrane. As in other eukaryotes, in plants, SNARE-mediated membrane traffic influences the density of several proteins at the plasma membrane. Even so, H+-ATPase traffic, its relationship with SNAREs, and its regulation by auxin have remained enigmatic. Here, we identify the Arabidopsis (Arabidopsis thaliana) Qa-SNARE SYP132 (Syntaxin of Plants132) as a key factor in H+-ATPase traffic and demonstrate its association with endocytosis. SYP132 is a low-abundant, secretory SNARE that primarily localizes to the plasma membrane. We find that SYP132 expression is tightly regulated by auxin and that augmented SYP132 expression reduces the amount of H+-ATPase proteins at the plasma membrane. The physiological consequences of SYP132 overexpression include reduced apoplast acidification and suppressed vegetative growth. Thus, SYP132 plays unexpected and vital roles in auxin-regulated H+-ATPase traffic and associated functions at the plasma membrane.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Cell Membrane
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Proton-Translocating ATPases
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Arabidopsis Proteins
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Qa-SNARE Proteins
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Plant Development
Type of study:
Prognostic_studies
Language:
En
Journal:
Plant Physiol
Year:
2019
Document type:
Article
Affiliation country: