Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2010-12-7
pubmed:abstractText
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 medium. Depletion of ammonium allowed normal root hair elongation in Atrop11(CA) plants, induced the development of longer root hairs in wild-type plants and suppressed the effect of Atrop11(CA) expression on actin organization and reactive oxygen species distribution, whereas membrane localization of the protein was not affected. Ammonium at concentrations higher than 1 mM and the presence of nitrate were required for induction of swelling. Oscillations in wall and cytoplasmic pH are known to accompany tip growth in root hairs, and buffering of the growth medium decreased Atrop11(CA)-induced swelling. Fluorescence ratio imaging experiments revealed that in wild-type root hairs, the addition of NH?NO? to the growth medium induced an increase in the amplitude of extracellular and intracellular pH oscillations and an overall decrease in cytoplasmic pH at the cell apex. Based on these results, we suggest a model in which ROP GTPases and nitrogen-dependent pH oscillations function in parallel pathways, creating a positive feedback loop during root hair growth.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
1365-3040
pubmed:author
pubmed:copyrightInfo
© 2010 Blackwell Publishing Ltd.
pubmed:issnType
Electronic
pubmed:volume
34
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
76-88
pubmed:meshHeading
pubmed-meshheading:20825579-Actins, pubmed-meshheading:20825579-Arabidopsis, pubmed-meshheading:20825579-Arabidopsis Proteins, pubmed-meshheading:20825579-Cell Differentiation, pubmed-meshheading:20825579-Green Fluorescent Proteins, pubmed-meshheading:20825579-Hydrogen-Ion Concentration, pubmed-meshheading:20825579-Meristem, pubmed-meshheading:20825579-Microscopy, Confocal, pubmed-meshheading:20825579-Morphogenesis, pubmed-meshheading:20825579-Nitrates, pubmed-meshheading:20825579-Nitrogen, pubmed-meshheading:20825579-Phenotype, pubmed-meshheading:20825579-Plant Roots, pubmed-meshheading:20825579-Plants, Genetically Modified, pubmed-meshheading:20825579-Quaternary Ammonium Compounds, pubmed-meshheading:20825579-Reactive Oxygen Species, pubmed-meshheading:20825579-Recombinant Fusion Proteins, pubmed-meshheading:20825579-Signal Transduction, pubmed-meshheading:20825579-rho GTP-Binding Proteins
pubmed:year
2011
pubmed:articleTitle
Nitrogen source interacts with ROP signalling in root hair tip-growth.
pubmed:affiliation
Department of Plant Sciences, Tel Aviv University, Tel Aviv, Israel Department of Botany, University of Wisconsin, Madison, WI, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't