Skip to main content

Main menu

  • Home
  • Content
    • Current Issue
    • Archive
    • Preview Papers
  • About
    • Editorial Board and Staff
    • About the Journal
    • Terms & Privacy
  • More
    • Alerts
    • Contact Us
  • Submit a Manuscript
    • Instructions for Authors
    • Submit a Manuscript
  • Other Publications
    • Plant Physiology
    • The Plant Cell
    • Plant Direct
    • The Arabidopsis Book
    • Teaching Tools in Plant Biology
    • ASPB
    • Plantae

User menu

  • My alerts
  • Log in

Search

  • Advanced search
Plant Cell
  • Other Publications
    • Plant Physiology
    • The Plant Cell
    • Plant Direct
    • The Arabidopsis Book
    • Teaching Tools in Plant Biology
    • ASPB
    • Plantae
  • My alerts
  • Log in
Plant Cell

Advanced Search

  • Home
  • Content
    • Current Issue
    • Archive
    • Preview Papers
  • About
    • Editorial Board and Staff
    • About the Journal
    • Terms & Privacy
  • More
    • Alerts
    • Contact Us
  • Submit a Manuscript
    • Instructions for Authors
    • Submit a Manuscript
  • Follow PlantCell on Twitter
  • Visit PlantCell on Facebook
  • Visit Plantae
OtherIN BRIEF
You have accessRestricted Access

Guard Cell Proteome Reveals Signals and Surprises

Jennifer Mach
Jennifer Mach
Science Editor
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site

Published December 2008. DOI: https://doi.org/10.1105/tpc.108.201214

  • Article
  • Figures & Data
  • Info & Metrics
  • PDF
Loading
  • American Society of Plant Biologists

Guard cell (GC) pairs regulate plant gas exchange and water loss by controlling the size of the stomate, the opening between them. Not an open and shut case, the regulation of stomatal size responds to a complex interplay of signals that transduce multiple environmental cues, including humidity, CO2 levels, abiotic stresses, pathogens, and light. These signals are integrated through the action of ion pumps and channels to produce a change in the size of the stomatal aperture; for example, in GC opening, the action of proton pumps hyperpolarizes the cell membrane and activates voltage-gated K+ ion channels. Ions flow in, and water follows, thereby increasing GC volume. The cell walls of the GC are structured such that this increase in cell volume causes the stomate to open (reviewed in Pandey et al., 2007). Abscisic acid (ABA) signaling of plant water status is particularly important in GC function: ABA both inhibits stomatal opening and induces stomatal closure.

GCs are a model system for signal transduction and have been examined using a plethora of techniques. Zhao et al. (pages 3210–3226) have now brought proteomics tools to bear on the examination of GC function, isolating GCs and determining their protein composition. Upon digestion of isolated epidermal pieces with cell wall–degrading enzymes, GCs are the last cell type to be released as protoplasts due to their thick cell walls. This differential susceptibility to enzymatic digestion can be exploited to obtain strikingly pure preparations of GC protoplasts (see figure , left) appropriate for single-cell-type proteome analysis.

Figure1
  • Download figure
  • Open in new tab
  • Download powerpoint

Purified guard cell protoplasts (left) yield a pattern of protein spots on a 2D gel (center). Mutant analysis of GCs lacking TGG1, the protein present in the strongest spot, reveals a decreased sensitivity to ABA (right, comparing current flow in the wild type at the top and in the mutant at the bottom).

The authors applied this method to 100 preparations from an amazing 22,000 Arabidopsis plants to isolate 3 × 108 GC protoplasts. They then used multiple proteomics methods, including 2D gels and the gel-free method of 2D liquid chromatography–matrix assisted laser desorption/ionization multidimensional protein identification technology, to identify 1734 unique proteins. This extensive single-cell proteome includes many proteins not previously identified from analysis of the GC transcriptome. Comparisons with the whole predicted Arabidopsis proteome, with the reported proteomes of leaves and other organs and with the set of genes known to function in GCs, yielded many intriguing candidates for future research.

One protein of remarkably high abundance in GCs (figure, center) was identified as THIOGLUCOSIDE GLUCOHYDROLASE1 (TGG1), an enzyme that hydrolyses glucosinolates, resulting (after subsequent steps) in the formation of isothiocyanates and other compounds toxic to microbes and herbivores (Barth and Jander, 2006). In this study, the authors found that tgg1 mutants have decreased sensitivity to ABA inhibition of K+ uptake channels and stomatal opening (figure, right); thus, the authors complete the scientific circle from protoplasts, through proteins, to phenotype. Given the usefulness of GCs as a model system and the importance of stomatal regulation in agriculture, the proteins identified in this study are likely to be important targets for future research.

Footnotes

  • www.plantcell.org/cgi/doi/10.1105/tpc.108.201214

References

  1. ↵
    Barth, C., and Jander, G. (2006). Arabidopsis myrosinases TGG1 and TGG2 have redundant function in glucosinolate breakdown and insect defense. Plant J. 46: 549–562.
    OpenUrlCrossRefPubMed
  2. ↵
    Pandey, S., Zhang, W., and Assmann, S.M. (2007). Roles of ion channels and transporters in guard cell signal transduction. FEBS Lett. 581: 2325–2336.
    OpenUrlCrossRefPubMed
  3. Zhao, Z., Zhang, W., Stanley, B.A., and Assmann, S.M. (2008). Functional proteomics of Arabidopsis thaliana guard cells uncovers new stomatal signaling pathways. Plant Cell 20: 3210–3226.
    OpenUrlAbstract/FREE Full Text
PreviousNext
Back to top

Table of Contents

Print
Download PDF
Email Article

Thank you for your interest in spreading the word on Plant Cell.

NOTE: We only request your email address so that the person you are recommending the page to knows that you wanted them to see it, and that it is not junk mail. We do not capture any email address.

Enter multiple addresses on separate lines or separate them with commas.
Guard Cell Proteome Reveals Signals and Surprises
(Your Name) has sent you a message from Plant Cell
(Your Name) thought you would like to see the Plant Cell web site.
CAPTCHA
This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.
Citation Tools
Guard Cell Proteome Reveals Signals and Surprises
Jennifer Mach
The Plant Cell Dec 2008, 20 (12) 3185; DOI: 10.1105/tpc.108.201214

Citation Manager Formats

  • BibTeX
  • Bookends
  • EasyBib
  • EndNote (tagged)
  • EndNote 8 (xml)
  • Medlars
  • Mendeley
  • Papers
  • RefWorks Tagged
  • Ref Manager
  • RIS
  • Zotero
Request Permissions
Share
Guard Cell Proteome Reveals Signals and Surprises
Jennifer Mach
The Plant Cell Dec 2008, 20 (12) 3185; DOI: 10.1105/tpc.108.201214
del.icio.us logo Digg logo Reddit logo Twitter logo CiteULike logo Facebook logo Google logo Mendeley logo
  • Tweet Widget
  • Facebook Like
  • Google Plus One

Jump to section

  • Article
    • Footnotes
    • References
  • Figures & Data
  • Info & Metrics
  • PDF

In this issue

The Plant Cell Online: 20 (12)
The Plant Cell
Vol. 20, Issue 12
December 2008
  • Table of Contents
  • Table of Contents (PDF)
  • About the Cover
  • Index by author
  • Advertising (PDF)
  • Back Matter (PDF)
  • Front Matter (PDF)
View this article with LENS

More in this TOC Section

  • Hold Me, Fold Me...or Not!
  • Slice and Dice: DCL2 Mediates the Production of 22-Nucleotide siRNAs that Influence Trait Variation in Soybean
  • How to Eat One’s Feelings: Autophagy and Phosphatidylinositol 3-Phosphate
Show more IN BRIEF

Similar Articles

Our Content

  • Home
  • Current Issue
  • Plant Cell Preview
  • Archive
  • Teaching Tools in Plant Biology
  • Plant Physiology
  • Plant Direct
  • Plantae
  • ASPB

For Authors

  • Instructions
  • Submit a Manuscript
  • Editorial Board and Staff
  • Policies
  • Recognizing our Authors

For Reviewers

  • Instructions
  • Peer Review Reports
  • Journal Miles
  • Transfer of reviews to Plant Direct
  • Policies

Other Services

  • Permissions
  • Librarian resources
  • Advertise in our journals
  • Alerts
  • RSS Feeds
  • Contact Us

Copyright © 2021 by The American Society of Plant Biologists

Powered by HighWire