Root hairs show highly localized cell expansion focused to their growing tips. This growth pattern is accomplished through restriction of secretion the elongating apex and modulation wall properties, with just behind tip becoming rigidified resist lateral expansive forces turgor. In this report we that root exhibit oscillating associated increases in extracellular pH reactive oxygen species (ROS), which lag by ≈7 s. Consistent a role for these changes control, artificially increasing...

Abstract Mechanical stimulation of plants triggers a cytoplasmic Ca2+ increase that is thought to link the touch stimulus appropriate growth responses. We found in roots Arabidopsis thaliana, external and endogenously generated mechanical forces consistently trigger rapid transient increases cytosolic signatures these transients are specific. likewise elicited an apoplastic alkalinization acidification as well reactive oxygen species (ROS) production. These responses showed same kinetics...

Abstract In tip-growing cells, the tip-high Ca2+ gradient is thought to regulate activity of components growth machinery, including cytoskeleton, Ca2+-dependent regulatory proteins, and secretory apparatus. pollen tubes, both cell elongation show oscillatory behavior, reinforcing link between two. We report that in growing root hairs Arabidopsis (Arabidopsis thaliana), an oscillating tip-focused can be resolved through imaging a cytosolically expressed Yellow Cameleon 3.6 fluorescence...

Plants adapt to a changing environment by entraining their growth and development prevailing conditions. Such 'plastic' requires highly dynamic integration of phenomena with signal perception transduction systems, such as occurs during tropic growth. The plant hormone auxin has been shown play key role in regulating these directional responses organs environmental cues. However, we are still lacking cellular molecular understanding how auxin-dependent signaling cascades link stimulus the...

Abstract Unlike mammals, whose development is limited to a short temporal window, plants produce organs de novo throughout their lifetime in order adapt architecture the prevailing environmental conditions. The production of lateral roots represents one example such postembryonic organogenesis. An endogenous developmental program likely imposes an ordered arrangement on position new roots. However, stimuli as nutrient levels also affect patterning root production. In addition, we have found...

The hormone auxin and reactive oxygen species (ROS) regulate root elongation, but the interactions between two pathways are not well understood. aim of this study was to investigate how interacts with ROS in regulating elongation tomato, Solanum lycopersicum. Wild-type auxin-resistant mutant, diageotropica (dgt), tomato (S. lycopersicum ‘Ailsa Craig’) were characterized terms apical meristem zone histology, expression cell-cycle marker gene Sl-CycB1;1, accumulation ROS, response hydrogen...

Rapid alkalinization factor (RALF) is a 49-amino-acid peptide that rapidly alkalinizes cultivated tobacco cell cultures. In the native Nicotiana attenuata, NaRALF occurs as single-copy gene and highly expressed in roots petioles. Silencing transcript by transforming N. attenuata with an inverted-repeat construct generated plants (irRALF) normal wild-type (WT) above-ground parts, but grew longer produced trichoblasts developed into abnormal root hairs. Most localized 'bulge' without...

Transient increases in the cytoplasmic Ca(2+) concentration are key events that initiate many cellular signaling pathways response to developmental and environmental cues plants; however, only a few extracellular mediators regulating singling known date. To identify endogenous cell peptides signaling, Arabidopsis seedlings expressing aequorin were used for an vivo luminescence assay changes. These challenged with fractions derived from plant extracts. Multiple heat-stable, protease-sensitive...

Summary Heterotrimeric G proteins composed of α, β and γ subunits regulate a number fundamental processes concerned with growth development in plants. In addition to the canonical heterotrimeric proteins, plants also contain small family extra large (XLGs) that show significant similarity G‐protein α subunit their C‐terminal regions. this paper we one three XLG genes, XLG3 , Gβ (AGB1) Arabidopsis heterotrimer are specifically involved regulation subset root morphological responses. Based on...

Root hairs elongate in a highly polarized manner known as tip growth. Overexpression of constitutively active Rho Plant (ROP)/RAC GTPases mutants induces swelling root hairs. Here, we demonstrate that Atrop11(CA)-induced depends on the composition growth medium. Depletion ammonium allowed normal hair elongation Atrop11(CA) plants, induced development longer wild-type plants and suppressed effect expression actin organization reactive oxygen species distribution, whereas membrane localization...

ABSTRACT The extracellular proton activity along primary roots of Phelcum pratense L. was measured using proton‐selective microelectrodes. Removal the root cap caused a reduction influx in transitional region between meristem and apical elongation zone vertical inhibited development pH differences physically upper lower flanks gravis‐stimulated root. Disruption actin filament system with 5 mmol m −3 cytochalasin D did not result an altered flux pattern compared untreated control roots, but...

ABSTRACT The effect of K + deficiency on the plasma membrane (PM) H ‐ATPase was studied in young stems poplar plants ( Populus tremula × tremuloides ) grown with low or full‐strength supply. Immunological assays using different antibodies were applied to test if affects amount immunodetectable PM ‐ATPases stem tissue. monoclonal antibody clone 46 E5 B11 revealed an increased abundance under conditions supply, and immunolabelling experiments showed that this increase restricted...

Growth of plant cells involves tight regulation the cytoskeleton and vesicle trafficking by processes including action 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 in Plant Cell Environment we show that ROPs/RACs function synergistically NH4NO3-modulated pH fluctuations to regulate root hair growth. Root hairs expand exclusively at their apical end strictly polarized manner...

Abstract: In order to study the effect of mechanical stimulation on membrane potential (E m ) roots Lepidium sativum L., were subjected pulses perfusion medium expelled from a micropipette positioned 1 mm root surface at level elongation zone. On opposite side root, microelectrode was inserted into rhizodermal or cortical cells zone record during such pulse. A pulse elicited fast transient hyperpolarisation up −38 mV, reaching peak approx. min after start Both degassing and increasing buffer...