1. An S-Acylation Switch of Conserved G Domain Cysteines Is Required for Polarity Signaling by ROP GTPases

    Current Biology 25(21):2875 (2015)

  2. Protein lipid modifications and the regulation of ROP GTPase function.

    Journal of Experimental Botany 66(6):1617 (2015) PMID 25711710

    In eukaryotes, the RHO superfamily of small G-proteins is implicated in the regulation of cell polarity and growth. Rho of Plants (ROPs)/RACs are plant-specific Rho family proteins that have been shown to regulate cell polarity, auxin transport and responses, ABA signalling, and response to path...
  3. Bimodal regulation of ICR1 levels generates self-organizing auxin distribution.

    PNAS 111(50):E5471 (2014) PMID 25468974 PMCID PMC4273421

    Auxin polar transport, local maxima, and gradients have become an important model system for studying self-organization. Auxin distribution is regulated by auxin-dependent positive feedback loops that are not well-understood at the molecular level. Previously, we showed the involvement of the RH...
  4. Editorial overview: cell biology.

    Current Opinion in Plant Biology 22:v (2014) PMID 25467971

  5. Editorial overview: Cell biology

    Current Opinion in Plant Biology 22 (2014)

  6. Cell polarity signaling.

    Current Opinion in Plant Biology 16(6):734 (2013) PMID 24238831

    Cell polarity is a fundamental entity of living organisms. Cells must receive accurate decisions where to divide and along which plane, along which axis to grow, where to grow structures like flagellum or filopodium and how to differentially respond to external stimuli. In multicellular organism...
  7. The Arabidopsis Rho of plants GTPase AtROP6 functions in developmental and pathogen response pathways.

    Plant Physiology 161(3):1172 (2013) PMID 23319551 PMCID PMC3585588

    How plants coordinate developmental processes and environmental stress responses is a pressing question. Here, we show that Arabidopsis (Arabidopsis thaliana) Rho of Plants6 (AtROP6) integrates developmental and pathogen response signaling. AtROP6 expression is induced by auxin and detected in t...
  8. Analysis of protein prenylation and S-acylation using gas chromatography-coupled mass spectrometry.

    Methods in Molecular Biology 1043:121 (2013) PMID 23913042

    Lipid modifications play a key role in protein targeting and function. The two Arabidopsis Gγ subunits, AGG1 and AGG2, have been shown to undergo prenylation (AGG1) and S-acylation (AGG2). Prenylation involves covalent nonreversible attachment of either farnesyl (15 carbons) or geranylgeranyl (2...
  9. S-acylation-dependent association of the calcium sensor CBL2 with the vacuolar membrane is essential for proper abscisic acid responses.

    Cell Research 22(7):1155 (2012) PMID 22547024 PMCID PMC3391015

    Calcineurin B-like (CBL) proteins contribute to decoding calcium signals by interacting with CBL-interacting protein kinases (CIPKs). Currently, there is still very little information about the function and specific targeting mechanisms of CBL proteins that are localized at the vacuolar membrane...
  10. How prenylation and S-acylation regulate subcellular targeting and function of ROP GTPases.

    Plant Signaling & Behavior 6(7):1026 (2011) PMID 21694496 PMCID PMC3257786

    Rho of Plants (ROP) small G proteins function at discrete domains of the plasma and possibly endo membranes. ROPs are synthesized as soluble proteins and their attachment to membranes and partitioning in membrane microdomains are facilitated by the posttranslational lipid modifications prenylati...
  11. RAC/ROP GTPases and auxin signaling.

    Plant Cell 23(4):1208 (2011) PMID 21478442 PMCID PMC3101531

    Auxin functions as a key morphogen in regulating plant growth and development. Studies on auxin-regulated gene expression and on the mechanism of polar auxin transport and its asymmetric distribution within tissues have provided the basis for realizing the molecular mechanisms underlying auxin f...
  12. Co-regulation of root hair tip growth by ROP GTPases and nitrogen source modulated pH fluctuations.

    Plant Signaling & Behavior 6(3):426 (2011) PMID 21673509 PMCID PMC3142429

    Growth of plant cells involves tight regulation of the cytoskeleton and vesicle trafficking by processes including the action of the ROP small G proteins together with pH-modulated cell wall modifications. Yet, little is known on how these systems are coordinated. In a paper recently published i...
  13. Differential effects of prenylation and s-acylation on type I and II ROPS membrane interaction and function.

    Plant Physiology 155(2):706 (2011) PMID 21139084 PMCID PMC3032461

    Prenylation primarily by geranylgeranylation is required for membrane attachment and function of type I Rho of Plants (ROPs) and Gγ proteins, while type II ROPs are attached to the plasma membrane by S-acylation. Yet, it is not known how prenylation affects ROP membrane interaction dynamics and ...
  14. Nitrogen source interacts with ROP signalling in root hair tip-growth.

    Plant, Cell & Environment 34(1):76 (2011) PMID 20825579

    Root hairs elongate in a highly polarized manner known as tip growth. Overexpression of constitutively active Rho of Plant (ROP)/RAC GTPases mutants induces swelling of root hairs. Here, we demonstrate that Atrop11(CA)-induced swelling of root hairs depends on the composition of the growth mediu...
  15. An auxin regulated positive feedback loop integrates Rho modulated cell polarity with pattern formation.

    Plant Signaling & Behavior 5(6):709 (2010) PMID 20383060 PMCID PMC3001566

    In plants, polar transport of the hormone auxin between cells connects cell polarity and pattern formation and is thus required for plant development. The direction of auxin transport is determined by polar localization of PIN auxin efflux transporters. The dynamic polar localization of PIN prot...
  16. An S-acylation switch of conserved G domain cysteines is required for polarity signaling by ROP GTPases.

    Current Biology 20(10):914 (2010) PMID 20451389

    Rho GTPases are master regulators of cell polarity. For their function, Rhos must associate with discrete plasma membrane domains. Rho of Plants (ROPs) or RACs comprise a single family. Prenylation and S-acylation of hypervariable domain cysteines of Ras and Rho GTPases are required for their fu...
  17. Analysis of protein S-acylation by gas chromatography-coupled mass spectrometry using purified proteins.

    Nature Protocols 5(5):834 (2010) PMID 20379138

    S-acylation, also known as palmitoylation, involves the attachment of acyl fatty acids to thiol groups of cysteine residues through a reversible thioester bond. Owing to its reversibility, S-acylation is important in regulation of diverse signaling cascades, including Ras-associated cancers in m...
  18. A rho scaffold integrates the secretory system with feedback mechanisms in regulation of auxin distribution.

    PLoS Biology 8(1):e1000282 (2010) PMID 20098722 PMCID PMC2808208

    Development in multicellular organisms depends on the ability of individual cells to coordinate their behavior by means of small signaling molecules to form correctly patterned tissues. In plants, a unique mechanism of directional transport of the signaling molecule auxin between cells connects ...
  19. Utilizing bimolecular fluorescence complementation (BiFC) to assay protein-protein interaction in plants.

    Methods in Molecular Biology 655:347 (2010) PMID 20734272

    Protein function is often mediated by the formation of stable or transient complexes. Here we present a method for testing protein-protein interactions in plants designated bimolecular fluorescence complementation (BiFC). The advantages of BiFC are its simplicity, reliability, and the ability to...
  20. Protein lipid modifications in signaling and subcellular targeting.

    Current Opinion in Plant Biology 12(6):714 (2009) PMID 19796984

    Classically perceived as means for recruiting proteins to the membranes, protein lipid modifications are known today to play diverse roles in subcellular targeting, protein-protein interactions and signaling. This review focuses on three protein lipid modifications: prenylation, S-acylation and ...