scholarly journals Nod Factors Alter the Microtubule Cytoskeleton in Medicago truncatula Root Hairs to Allow Root Hair Reorientation

2005 ◽  
Vol 18 (11) ◽  
pp. 1195-1204 ◽  
Author(s):  
Björn J. Sieberer ◽  
Antonius C. J. Timmers ◽  
Anne Mie C. Emons
Keyword(s):  
Medicago Truncatula ◽  
Root Hair ◽  
Tip Growth ◽  
Root Hairs ◽  
High Density ◽  
Nod Factors ◽  
Microtubule Cytoskeleton ◽  
Nod Factor ◽  
Set Up ◽  
Drug Studies

The microtubule (MT) cytoskeleton is an important part of the tip-growth machinery in legume root hairs. Here we report the effect of Nod factor (NF) on MTs in root hairs of Medicago truncatula. In tip-growing hairs, the ones that typically curl around rhizobia, NF caused a subtle shortening of the endoplasmic MT array, which recovered within 10 min, whereas cortical MTs were not visibly affected. In growth-arresting root hairs, endoplasmic MTs disappeared shortly after NF application, but reformed within 20 min, whereas cortical MTs remained present in a high density. After NF treatment, growth-arresting hairs were swelling at their tips, after which a new outgrowth formed that deviated with a certain angle from the former growth axis. MT depolymerization with oryzalin caused a growth deviation similar to the NF; whereas, combined with NF, oryzalin increased and the MT-stabilizing drug taxol suppressed NF-induced growth deviation. The NF-induced disappearance of the endoplasmic MTs correlated with a loss of polar cytoarchitecture and straight growth directionality, whereas the reappearance of endoplasmic MTs correlated with the new set up of polar cytoarchitecture. Drug studies showed that MTs are involved in determining root hair elongation in a new direction after NF treatment.

scholarly journals The Small GTPase ROP10 of Medicago truncatula Is Required for Both Tip Growth of Root Hairs and Nod Factor-Induced Root Hair Deformation

2015 ◽  
Vol 27 (3) ◽  
pp. 806-822 ◽  
Author(s):  
Ming-Juan Lei ◽  
Qi Wang ◽  
Xiaolin Li ◽  
Aimin Chen ◽  
Li Luo ◽  
...  
Keyword(s):  
Medicago Truncatula ◽  
Root Hair ◽  
Tip Growth ◽  
Root Hairs ◽  
Small Gtpase ◽  
Nod Factor ◽  
Root Hair Deformation

scholarly journals Rhizobium Nod Factors Induce an Increase in Sub-apical Fine Bundles of Actin Filaments in Vicia sativa Root Hairs within Minutes

1999 ◽  
Vol 12 (9) ◽  
pp. 829-832 ◽  
Author(s):  
Norbert C. A. de Ruijter ◽  
Ton Bisseling ◽  
Anne Mie C. Emons
Keyword(s):  
Actin Cytoskeleton ◽  
Actin Filaments ◽  
Tip Growth ◽  
Developmental Stages ◽  
Root Hairs ◽  
Vicia Sativa ◽  
Nod Factors ◽  
Nod Factor

We studied the response of the actin cytoskeleton in vetch root hairs after application of host-specific Nod factor. Within 3 to 15 min, the number of sub-apical fine bundles of actin filaments (FB-actin) increased in all developmental stages. Tip growth resumed only in hairs in which the FB-actin density and the length of the region with FB-actin exceeded a minimal value.

scholarly journals Identical Accumulation and Immobilization of Sulfated and Nonsulfated Nod Factors in Host and Nonhost Root Hair Cell Walls

2003 ◽  
Vol 16 (10) ◽  
pp. 884-892 ◽  
Author(s):  
Joachim Goedhart ◽  
Jean-Jacques Bono ◽  
Ton Bisseling ◽  
Theodorus W. J. Gadella
Keyword(s):  
Hair Cell ◽  
Root Hair ◽  
Cell Walls ◽  
Root Hairs ◽  
Sharp Decrease ◽  
Biologically Active ◽  
Nod Factors ◽  
Nod Factor ◽  
Root Hair Cell ◽  
Root Hair Deformation

Nod factors are signaling molecules secreted by Rhizobium bacteria. These lipo-chitooligosaccharides (LCOs) are required for symbiosis with legumes and can elicit specific responses at subnanomolar concentrations on a compatible host. How plants perceive LCOs is unclear. In this study, using fluorescent Nod factor analogs, we investigated whether sulfated and nonsulfated Nod factors were bound and perceived differently by Medicago truncatula and Vicia sativa root hairs. The bioactivity of three novel sulfated fluorescent LCOs was tested in a root hair deformation assay on M. truncatula, showing bioactivity down to 0.1 to 1 nM. Fluorescence microscopy of plasmolyzed M. truncatula root hairs shows that sulfated fluorescent Nod factors accumulate in the cell wall of root hairs, whereas they are absent from the plasma membrane when applied at 10 nM. When the fluorescent Nod factor distribution in medium surrounding a root was studied, a sharp decrease in fluorescence close to the root hairs was observed, visualizing the remarkable capacity of root hairs to absorb Nod factors from the medium. Fluorescence correlation microscopy was used to study in detail the mobilities of sulfated and nonsulfated fluorescent Nod factors which are biologically active on M. truncatula and V. sativa, respectively. Remarkably, no difference between sulfated and nonsulfated Nod factors was observed: both hardly diffuse and strongly accumulate in root hair cell walls of both M. truncatula and V. sativa. The implications for the mode of Nod factor perception are discussed.

Ethylene provides positional information on cortical cell division but is not involved in Nod factor-induced root hair tip growth in Rhizobium-legume interaction

Development ◽  
1997 ◽  
Vol 124 (9) ◽  
pp. 1781-1787 ◽  
Author(s):  
R. Heidstra ◽  
W.C. Yang ◽  
Y. Yalcin ◽  
S. Peck ◽  
A.M. Emons ◽  
...  
Keyword(s):  
Cell Division ◽  
Root Hair ◽  
Rhizobium Leguminosarum ◽  
Tip Growth ◽  
Cortical Cell ◽  
Acc Oxidase ◽  
Positional Information ◽  
Nod Factors ◽  
Nod Factor ◽  
Root Hair Deformation

Nod factors secreted by Rhizobium leguminosarum bv. viciae induce root hair deformation, involving a reinitiation of tip growth, and the formation of nodule primordia in Vicia sativa (vetch). Ethylene is a potent inhibitor of cortical cell division, an effect that can be counteracted by applying silver ions (Ag+) or aminoethoxy-vinylglycine (AVG). In contrast to the inhibitory effect on cortical cell division, ethylene promotes the formation of root hairs (which involves tip growth) in the root epidermis of Arabidopsis. We investigate the possible paradox concerning the action of ethylene, putatively promoting Nod factor induced tip growth whilst, at the same time, inhibiting cortical cell division. We show, by using the ethylene inhibitors AVG and Ag+, that ethylene has no role in the reinitiation of root hair tip growth induced by Nod factors (root hair deformation) in vetch. However, root hair formation is controlled, at least in part, by ethylene. Furthermore, we show that ACC oxidase, which catalizes the last step in ethylene biosynthesis, is expressed in the cell layers opposite the phloem in that part of the root where nodule primordia are induced upon inoculation with Rhizobium. Therefore, we test whether endogenously produced ethylene provides positional information controlling the site where nodule primordia are formed by determining the position of nodules formed on pea roots grown in the presence of AVG or Ag+.

scholarly journals Heterologous Expression of Rhizobial CelC2 Cellulase Impairs Symbiotic Signaling and Nodulation in Medicago truncatula

2018 ◽  
Vol 31 (5) ◽  
pp. 568-575 ◽  
Author(s):  
Marta Robledo ◽  
Esther Menéndez ◽  
Jose Ignacio Jiménez-Zurdo ◽  
Raúl Rivas ◽  
Encarna Velázquez ◽  
...  
Keyword(s):  
Medicago Truncatula ◽  
Cell Walls ◽  
Rhizobium Leguminosarum ◽  
Root Nodules ◽  
Root Hairs ◽  
Nod Factors ◽  
Model Legume ◽  
Ensifer Meliloti ◽  
Early Nodulin ◽  
The Impact

The infection of legume plants by rhizobia is tightly regulated to ensure accurate bacterial penetration, infection, and development of functionally efficient nitrogen-fixing root nodules. Rhizobial Nod factors (NF) have key roles in the elicitation of nodulation signaling. Infection of white clover roots also involves the tightly regulated specific breakdown of the noncrystalline apex of cell walls in growing root hairs, which is mediated by Rhizobium leguminosarum bv. trifolii cellulase CelC2. Here, we have analyzed the impact of this endoglucanase on symbiotic signaling in the model legume Medicago truncatula. Ensifer meliloti constitutively expressing celC gene exhibited delayed nodulation and elicited aberrant ineffective nodules, hampering plant growth in the absence of nitrogen. Cotreatment of roots with NF and CelC2 altered Ca2+ spiking in root hairs and induction of the early nodulin gene ENOD11. Our data suggest that CelC2 alters early signaling between partners in the rhizobia-legume interaction.

scholarly journals AtRBOHC/RHD2 vesicular delivery to the apical plasma membrane domain during root hair development

2021 ◽  
Author(s):  
Lenka Kuběnová ◽  
Michaela Tichá ◽  
Jozef Šamaj ◽  
Miroslav Ovečka
Keyword(s):  
Plasma Membrane ◽  
Quantitative Analysis ◽  
Root Hair ◽  
Tip Growth ◽  
Root Hairs ◽  
Apical Plasma Membrane ◽  
Loss Of Function ◽  
Short Root ◽  
Early Endosomes ◽  
Root Hair Initiation

AbstractArabidopsis root hairs develop as long tubular extensions from the rootward pole of trichoblasts and exert polarized tip growth. The establishment and maintenance of root hair polarity is a complex process involving the local apical production of reactive oxygen species (ROS) generated by NADPH oxidase RESPIRATORY BURST OXIDASE HOMOLOG PROTEIN C/ROOT HAIR DEFECTIVE 2 (AtRBOHC/RHD2). It has been shown that loss-of-function rhd2 mutants have short root hairs that are unable to elongate by tip growth, and this phenotype was fully complemented by GFP-RHD2 expressed under the RHD2 promoter. However, the spatiotemporal mechanism of AtRBOHC/RHD2 subcellular redistribution and delivery to the plasma membrane (PM) during root hair initiation and tip growth are still unclear. Here, we used advanced microscopy for detailed qualitative and quantitative analysis of vesicular compartments containing GFP-RHD2 and characterization of their movements in developing bulges and growing root hairs. These compartments, identified by an independent marker such as the trans-Golgi network (TGN), deliver GFP-RHD2 to the apical PM domain, the extent of which correlates with the stage of root hair formation. Movements of TGN/early endosomes, but not late endosomes, were affected in the bulging domains of the rhd2-1 mutant. Finally, we reveal that accumulation in the growing tip, docking, and incorporation of TGN compartments containing GFP-RHD2 to the apical PM of root hairs requires structural sterols. These results help clarify the mechanism of polarized AtRBOHC/RHD2 targeting, maintenance, and recycling at the apical PM domain, coordinated with different developmental stages of root hair initiation and growth.One-sentence summaryAdvanced microscopy and quantitative analysis of vesicular TGN compartments revealed that delivering GFP-RHD2 to the apical plasma membrane domains of developing bulges and growing root hairs requires structural sterols.

scholarly journals Functional Characterization of fer-ts, a Temperature-Sensitive FERONIA Mutant Allele That Alters Root Hair Growth

2020 ◽  
Author(s):  
Daewon Kim ◽  
Jiyuan Yang ◽  
Fangwei Gu ◽  
Sung Jin Park ◽  
Jonathon Combs ◽  
...  
Keyword(s):  
Root Hair ◽  
Plasma Membranes ◽  
Tip Growth ◽  
Elevated Temperatures ◽  
Functional Characterization ◽  
Root Hairs ◽  
Temperature Sensitive ◽  
Genetic Screens ◽  
Binding Domains ◽  
Cellular Components

ABSTRACTIn plants, root hairs undergo a highly-polarized form of cell expansion called tip-growth, in which cell wall deposition is restricted to the root hair apex. In order to identify essential cellular components that might have been missed in earlier genetic screens we identified conditional temperature sensitive (ts) root hair mutants by EMS mutagenesis. Here we describe one of these mutants, fer-ts (feronia-temperature sensitive). Mutant fer-ts seedlings grew normally at normal temperatures (20°C), but failed to form root hairs at elevated temperatures (30°C). Map based-cloning and whole genome sequencing revealed that fer-ts resulted from a G41S substitution in the extracellular domain of FERONIA (FER). A functional fluorescent fusion of FER containing the fer-ts mutation localized to plasma membranes, but was subject to enhanced protein turnover at elevated temperatures. While tip-growth was rapidly inhibited by addition of RALF1 peptides in both wild-type and fer-ts mutants at normal temperatures, root elongation of fer-ts seedlings was resistant to added RALF1 peptide at elevated temperatures. Additionally, at elevated temperatures fer-ts seedlings displayed altered ROS accumulation upon auxin treatment and phenocopied constitutive fer mutant responses to a variety of plant hormone treatments. Molecular modeling and sequence comparison with other CrRLK1L receptor family members revealed that the mutated glycine in fer-ts is highly conserved, but is not located in the recently characterized RALF23 and LORELI-LIKE-GLYCOPROTEIN (LLG2) binding domains, perhaps suggesting that fer-ts phenotypes may not be directly due to loss of binding to RALF1 peptides.

scholarly journals Induction of Chalcone Synthase Expression by Rhizobia and Nod factors in Root Hairs and Roots

1997 ◽  
Vol 10 (3) ◽  
pp. 388-393 ◽  
Author(s):  
Andrea Krause ◽  
Vo T. T. Lan ◽  
William J. Broughton
Keyword(s):  
Chalcone Synthase ◽  
Root Hairs ◽  
Signal Transduction Pathway ◽  
Defense Responses ◽  
Nod Factors ◽  
Nod Factor ◽  
Transcript Levels ◽  
Gene Transcripts ◽  
Infection Pathway ◽  
Rhizobium Sp

Chalcone synthase (CHS) of Vigna unguiculata is encoded by a gene family that is abundantly transcribed in leaves and nodules. Inoculation with Rhizobium sp. NGR234, which nodulates V. unguiculata, or with NGRΔnodABC, a mutant deficient in Nod factor production, induced rapid accumulation of CHS mRNAs in roots and root hairs. As both Nod+ and Nod- bacteria provoke responses, induction of CHS gene expression may involve symbiotic or defense responses. Four days after inoculation with the wild-type Rhizobium sp., the transcript levels increased in roots but decreased in root hairs. Use of a region unique to the 5′ end of a specific CHS gene (VuCHS1) showed that increases of transcript levels in root hairs 24 h after inoculation with both rhizobia were specific to this gene. Transcripts of this gene in roots were only detectable 4 days after treatment with NGR234. It is possible therefore that accumulation of VuCHS1 follows the infection pathway of rhizobia entering legume roots. Purified Nod factors induced accumulation of transcripts, showing that they might be part of the signal transduction pathway leading to CHS expression.

Sign in / Sign up

Export Citation Format

Share Document