DOI: 10.5061/dryad.8kprr4xr9
title: Arabidopsis SAUR63 seedling phenotypes and fluorescent fusion protein localization

description: In plants, regulated cell expansion determines organ size and
 shape.  Several members of the family of redundantly acting Small
 Auxin Up RNA (SAUR) proteins can stimulate plasma membrane (PM) H+-ATPase
 proton pumping activity by inhibiting PM-associated PP2C.D phosphatases,
 thereby increasing the PM electrochemical potential, acidifying the
 apoplast, and stimulating cell expansion.  Similarly, Arabidopsis
 thaliana SAUR63 was able to increase growth of various organs, antagonize
 PP2C.D5 phosphatase, and increase H+-ATPase activity.  This
 dataset includes i) measurements of seedling growth in plants with altered
 activity of SAUR63 and PP2C.D5; ii) data from fluorescent images to
 measure extracellular pH; iii) analyses of subcellular localization of
 SAUR63:YFP fusion protein variants in roots; and iv) SAUR63:YFP
 localization after transient expression in Nicotiana benthamiana leaves
 with perturbed plasma membrane lipid composition.  These data
 underlie figures presented in the linked manuscript.  Using a
 gain-of-function approach to bypass genetic redundancy, we dissected
 structural requirements for SAUR63 growth-promoting activity. 
 The divergent N-terminal domain of SAUR63 has a predicted basic
 amphipathic α-helix, and was able to drive partial PM
 association.  Deletion of the N-terminal domain decreased PM
 association of a SAUR63 fusion protein, as well as decreasing protein
 level and eliminating growth-promoting activity.  Conversely,
 forced PM association restored ability to promote H+-ATPase activity and
 cell expansion, indicating that SAUR63 is active when
 PM-associated.  Lipid binding assays and perturbations of PM
 lipid composition indicate that the N-terminal domain can interact with PM
 anionic lipids.  Mutations in the conserved SAUR domain also
 reduced PM association in root cells.  Thus, both the N-terminal
 domain and the SAUR domain may cooperatively mediate the SAUR63 PM
 association required to promote growth.  Data is licensed by the
 authors for use and distribution subject to citation of the original
 source in accordance with the Creative Commons Attribution (CC BY)
 license.
description: 1. Description of methods used for collection/generation of data:
 <br>A link to the publication that incorporates this data will be
 provided here upon acceptance.  That publication describes methods for
 each experiment. <br><br>2. Methods for processing the data:
 <br>The submitted data for most tabs are raw measurements and are
 not processed.  Data for Figures S2 (calculated cell dimensions), 2I
 (calculated HPTS fluorescence ratios), and S5E (calculated HPTS
 fluorescence ratios) have already been processed, as indicated in the
 corresponding tabs.  <br><br>3. Instrument- or
 software-specific information needed to interpret the data: <br>A
 plugin for ImageJ was used to analyze HPTS fluorescence images in Figures
 2I and S5E, as described in: Barbez E, Dunser K, Gaidora A, Lendl T, Busch
 W. Auxin steers root cell expansion via apoplastic pH regulation in
 Arabidopsis thaliana. Proceedings of the National Academy of Sciences of
 the United States of America. 2017;114(24):E4884-E4893.
 <br><br>4. Standards and calibration information, if
 appropriate: <br>For length and area measurement data that are in
 raw format from ImageJ measurements of scanned images, the appropriate
 conversion factor to convert to standard units is listed with the data.
  <br><br>5. Environmental/experimental conditions:
 <br>Conditions for each experiment are listed within the
 corresponding data tab.  See also the Methods section of the associated
 publication.
description: The data are provided as an .xlsx file with multiple tabs, and
 can be opened with Microsoft Excel or other software.