Expression of MAX2 under SCARECROW promoter enhances the strigolactone/MAX2 dependent response of Arabidopsis roots to low-phosphate conditions.

MAX2/strigolactone signaling in the endodermis and/or quiescent center of the root is partially sufficient to exert changes in F-actin density and cellular trafficking in the root epidermis, and alter gene expression during plant response to low Pi conditions. Strigolactones (SLs) are a new group of plant hormones that regulate different developmental processes in the plant via MAX2, an F-box protein that interacts with their receptor. SLs and MAX2 are necessary for the marked increase in root-hair (RH) density in seedlings under conditions of phosphate (Pi) deprivation.

Arabidopsis response to low-phosphate conditions includes active changes in actin filaments and PIN2 polarization and is dependent on strigolactone signalling.

Strigolactones (SLs) are plant hormones that regulate the plant response to phosphate (Pi) growth conditions. At least part of SL-signalling execution in roots involves MAX2-dependent effects on PIN2 polar localization in the plasma membrane (PM) and actin bundling and dynamics. We examined PIN2 expression, PIN2 PM localization, endosome trafficking, and actin bundling under low-Pi conditions: a MAX2-dependent reduction in PIN2 trafficking and polarization in the PM, reduced endosome trafficking, and increased actin-filament bundling were detected in root cells.

Strigolactone analog GR24 triggers changes in PIN2 polarity, vesicle trafficking and actin filament architecture.

Strigolactones (SLs) are plant hormones that regulate shoot and root development in a MAX2-dependent manner. The mechanism underlying SLs' effects on roots is unclear. We used root hair elongation to measure root response to SLs.

Strigolactones are involved in root response to low phosphate conditions in Arabidopsis.

Strigolactones (SLs) are plant hormones that suppress lateral shoot branching, and act to regulate root hair elongation and lateral root formation. Here, we show that SLs are regulators of plant perception of or response to low inorganic phosphate (Pi) conditions. This regulation is mediated by MORE AXILLARY GROWTH2 (MAX2) and correlated with transcriptional induction of the auxin receptor TRANSPORT INHIBITOR RESPONSE1 (TIR1).

Light is a positive regulator of strigolactone levels in tomato roots.

Strigolactones (SLs) or closely related molecules were recently identified as phytohormones, acting as long-distance branching factors that suppress growth of pre-formed axillary buds in the shoot. The SL signaling pathways and light appear to be connected, as SLs were shown to induce light-regulated pathways and to mimic light-adapted plant growth. However, it is not yet clear how light affects SL levels.

Strigolactones interact with ethylene and auxin in regulating root-hair elongation in Arabidopsis.

Strigolactones (SLs) or derivatives thereof have been identified as phytohormones, and shown to act as long-distance shoot-branching inhibitors. In Arabidopsis roots, SLs have been suggested to have a positive effect on root-hair (RH) elongation, mediated via the MAX2 F-box. Two other phytohormones, auxin and ethylene, have been shown to have positive effects on RH elongation.

Strigolactones affect lateral root formation and root-hair elongation in Arabidopsis.

Strigolactones (SLs) have been proposed as a new group of plant hormones, inhibiting shoot branching, and as signaling molecules for plant interactions. Here, we present evidence for effects of SLs on root development. The analysis of mutants flawed in SLs synthesis or signaling suggested that the absence of SLs enhances lateral root formation.

Strigolactone deficiency confers resistance in tomato line SL-ORT1 to the parasitic weeds Phelipanche and Orobanche spp.

The parasitic flowering plants of the genera Orobanche and Phelipanche (broomrape species) are obligatory chlorophyll-lacking root-parasitic weeds that infect dicotyledonous plants and cause heavy economic losses in a wide variety of plant species in warm-temperate and subtropical regions. One of the most effective strategies for broomrape control is crop breeding for broomrape resistance. Previous efforts to find natural broomrape-resistant tomato (Solanum lycopersicon) genotypes were unsuccessful, and no broomrape resistance was found in any wild tomato species.

Strigolactones are positive regulators of light-harvesting genes in tomato.

Strigolactones are newly identified plant hormones, shown to participate in the regulation of lateral shoot branching and root development. However, little is known about their effects on biological processes, genes, and proteins. Transcription profiling of roots treated with GR24, a synthetic strigolactone with proven biological activity, and/or indole acetic acid (IAA) was combined with physiological and transcriptional analysis of a tomato mutant (Sl-ORT1) deficient in strigolactone production.

A tomato strigolactone-impaired mutant displays aberrant shoot morphology and plant interactions.

Strigolactones are considered a new group of plant hormones. Their role as modulators of plant growth and signalling molecules for plant interactions first became evident in Arabidopsis, pea, and rice mutants that were flawed in strigolactone production, release, or perception. The first evidence in tomato (Solanum lycopersicon) of strigolactone deficiency is presented here.

Microarray analysis and functional tests suggest the involvement of expansins in the early stages of symbiosis of the arbuscular mycorrhizal fungus Glomus intraradices on tomato (Solanum lycopersicum).

Arbuscular mycorrhizal (AM) symbiosis occurs between fungi of the phylum Glomeromycota and most terrestrial plants. However, little is known about the molecular symbiotic signalling between AM fungi (AMFs) and non-leguminous plant species. We sought to further elucidate the molecular events occurring in tomato, a non-leguminous host plant, during the early, pre-symbiotic stage of AM symbiosis, i.

Expression of streptavidin in tomato resulted in abnormal plant development that could be restored by biotin application.

Biotin is an essential cofactor for a variety of carboxylase and decarboxylase reactions and is involved in diverse metabolic pathways of all organisms. In the present study we tested the hypothesis that controlling biotin availability by the expression of Streptomyces avidinii streptavidin, would impede plant development. Transient expression of streptavidin fused to plant signal peptide, bacterial signal peptide or both, in tomato (Lycopersicon esculentum cv.

Root exudate of pmi tomato mutant M161 reduces AM fungal proliferation in vitro.

Soluble factors released from roots of the pre-mycorrhizal infection (pmi) myc(-) tomato mutant M161 were analyzed and compared with normal wild-type released factors. Aseptic whole exudates from the M161 mutant retarded the proliferation of Glomus intraradices in vitro. When the whole exudate was further fractionated on a C18 SEPAK cartridge, the 50/70% methanol fraction showed an activity against hyphal tip growth of Gigaspora gigantea and Gl.

Isolation of a premycorrhizal infection (pmi2) mutant of tomato, resistant to arbuscular mycorrhizal fungal colonization.

Arbuscular mycorrhizae (AM) represent an ancient symbiosis between mycorrhizal fungi and plant roots which co-evolved to exhibit a finely tuned, multistage interaction that assists plant growth. Direct screening efforts for Myc- plant mutants resulted in the identification of a tomato (Lycopersicon esculentum L. cv.

Overexpression of a plasma membrane aquaporin in transgenic tobacco improves plant vigor under favorable growth conditions but not under drought or salt stress.

Most of the symplastic water transport in plants occurs via aquaporins, but the extent to which aquaporins contribute to plant water status under favorable growth conditions and abiotic stress is not clear. To address this issue, we constitutively overexpressed the Arabidopsis plasma membrane aquaporin, PIP1b, in transgenic tobacco plants. Under favorable growth conditions, PIP1b overexpression significantly increased plant growth rate, transpiration rate, stomatal density, and photosynthetic efficiency.

Hormone concentrations in tobacco roots change during arbuscular mycorrhizal colonization with Glomus intraradices.

•  Phytohormones are known to play a pivotal role in various developmental processes in plants and in arbuscular-mycorrhizal (AM) fungal-host symbiosis. This study focuses on characterizing the changes in the concentrations of auxins, cytokinins and gibberellins in tobacco (Nicotiana tabacum) during the early stages of colonization by Glomus intraradices, using advanced analytical detection techniques. •  High-pressure liquid chromatography analysis followed by radioimmunoassay detection revealed that AM colonization induced the accumulation of specific zeatin riboside-like and isopentenyl adenosine-like compounds in both roots and shoots.