Abstract
It is known that plant cells can contain multiple distinct vacuoles; however, the abundance of multivacuolar cells and the mechanisms underlying vacuolar differentiation and communication among different types of vacuoles remain unknown. PH1 and PH5 are tonoplast P-ATPases that form a heteromeric pump that hyper-acidifies the central vacuole (CV) of epidermal cells in petunia petals. Here, we show that the sorting of this pump and other vacuolar proteins to the CV involves transit through small vacuoles: vacuolinos. Vacuolino formation is controlled by transcription factors regulating pigment synthesis and transcription of PH1 and PH5. Trafficking of proteins from vacuolinos to the central vacuole is impaired by misexpression of vacuolar SNAREs as well as mutants for the PH1 component of the PH1-PH5 pump. The finding that PH1-PH5 and these SNAREs interact strongly suggests that structural tonoplast proteins can act as tethering factors in the recognition of different vacuolar types.
| Original language | English |
|---|---|
| Pages (from-to) | 2413-2422 |
| Number of pages | 10 |
| Journal | Cell Reports |
| Volume | 19 |
| Issue number | 12 |
| DOIs | |
| Publication status | Published - 20 Jun 2017 |
Funding
We thank Erik Manders and Ronald Breedijk (Center of Advanced Microscopy, University of Amsterdam) for technical assistance with confocal microscopy, Daisy Kloos and Pieter Hoogeveen for plant care, and Lorenzo Frigerio for supplying the AtTIPs-YFP fusions. This work was supported by short-term EMBO fellowships (to M.F. and W.V.), fellowships of the Chinese Scholarship Council (to Y.L. and S.L.), and project n?14 ?Reti di Laboratori Pubblici di Ricerca, SELGE,? Regione Puglia (to G.P.D.S.).
| Funders | Funder number |
|---|---|
| European Molecular Biology Organization | |
| China Scholarship Council | |
| Regione Puglia |
Keywords
- membrane fusion
- membrane recognition
- multiple vacuoles
- SNARE complex
- tethering factors