The Arabidopsis V-ATPase is localized to the TGN/EE via a seed plant specific motif
- Heidelberg University, Germany
- National Institute for Basic Biology, Japan
Abstract
The V-ATPase is a versatile proton-pump found in a range of endomembrane compartments yet the mechanisms governing its differential targeting remain to be determined. In Arabidopsis, VHA-a1 targets the V-ATPase to the TGN/EE whereas VHA-a2 and VHA-a3 are localized to the tonoplast. We report here that the VHA-a1 targeting domain serves as both an ER-exit and as a TGN/EE-retention motif and is conserved among seed plants. In contrast, Marchantia encodes a single VHA-isoform that localizes to the TGN/EE and the tonoplast in Arabidopsis. Analysis of CRISPR/Cas9 generated null alleles revealed that VHA-a1 has an essential for male gametophyte development but acts redundantly with the tonoplast isoforms during vegetative growth. We propose that in the absence of VHA-a1, VHA-a3 is partially re-routed to the TGN/EE. Our findings contribute to understanding the evolutionary origin of V-ATPase targeting and provide a striking example that differential localization does not preclude functional redundancy.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Source data is provided for Figures 2,4B, 5B, 7B and C, 8C and D, 10A, Supplemental Figure 8B, Supplemental Figure 9 and Supplemental Figure 15A.
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The hornwort genome and early land plant evolutionDryad Digital Repository,10.5061/dryad.msbcc2ftv.
Article and author information
Author details
Funding
DFG (SFB1101 TPA02)
- Karin Schumacher
Grants-in-Aid for Scientific Research (19H05675,18H0247,18K14738)
- Takehiko Kanazawa
- Takashi Ueda
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Lupanga et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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The Arabidopsis V-ATPase is localized to the TGN/EE via a seed plant specific motif
eLife 9:e60568.
https://doi.org/10.7554/eLife.60568
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