Indoleacetic acid (IAA) is a breakdown product of tryptophan metabolism and is often produced by the action of bacteria in the mammalian gut. Some endogenous production of IAA in mammalian tissues also occurs. It may be produced by the decarboxylation of tryptamine or the oxidative deamination of tryptophan. IAA frequently occurs at low levels in urine and has been found in elevated levels in the urine of patients with phenylketonuria ((PMID: 13610897 ). Using material extracted from human urine, it was discovered by Kogl in 1933 that Indoleacetic acid is also an important plant hormone (PMID: 13610897 ). Specifically IAA is a member of the group of phytohormones called auxins. IAA is generally considered to be the most important native auxin. Plant cells synthesize IAA from tryptophan. (wikipedia) IAA and some derivatives can be oxidised by horseradish peroxidase (HRP) to cytotoxic species. IAA is only toxic after oxidative decarboxylation; the effect of IAA/HRP is thought to be due in part to ...
plant growth hormones for sale Manufacturers Directory - find plant growth hormones for sale from plant growth hormones for sale online Wholesalers for your sourcing needs from China.
The plant specific transcription factor LEAFY (LFY) plays a pivotal role in the developmental switch to floral meristem identity in Arabidopsis. Our recent study revealed that LFY additionally acts downstream of AUXIN RESPONSE FACTOR5/MONOPTEROS to promote flower primordium initiation. LFY also promotes initiation of the floral organ and floral organ identity. To further investigate the interplay between LFY and auxin during flower development, we examined the phenotypic consequence of disrupting polar auxin transport in lfy mutants by genetic means. Plants with compromised LFY activity exhibit increased sensitivity to disruption of polar auxin transport. Compromised polar auxin transport activity in the lfy mutant background resulted in formation of fewer floral organs, abnormal gynoecium development, and fused sepals. In agreement with these observations, expression of the auxin response reporter DR5rev::GFP as well as of the direct LFY target CUP-SHAPED COTYLEDON2 were altered in lfy mutant flowers.
The phytohormone auxin is transported through the plant body either via vascular pathways or from cell to cell by specialized polar transport machinery. This machinery consists of a balanced system of passive diffusion combined with the activities of auxin influx and efflux carriers. Synthetic auxins that differ in the mechanisms of their transport across the plasma membrane together with polar auxin transport inhibitors have been used in many studies on particular auxin carriers and their role in plant development. However, the exact mechanism of action of auxin efflux and influx inhibitors has not been fully elucidated. In this report, the mechanism of action of the auxin influx inhibitors (1-naphthoxyacetic acid (1-NOA), 2-naphthoxyacetic acid (2-NOA), and 3-chloro-4-hydroxyphenylacetic acid (CHPAA)) is examined by direct measurements of auxin accumulation, cellular phenotypic analysis, as well as by localization studies of Arabidopsis thaliana L. auxin carriers heterologously expressed in ...
PINOID, a serine threonine protein kinase in Arabidopsis, controls auxin distribution through a positive control of subcellular localization of PIN auxin efflux carriers. Compared with the rapid progress in understanding mechanisms of auxin action in dicot species, little is known about auxin action in monocot species. Here, we describe the identification and characterization of OsPID, the PINOID ortholog of rice. Phylogenetic analysis showed that the rice genome contains a single PID ortholog, OsPID. Constitutive overexpression of OsPID caused a variety of abnormalities, such as delay of adventitious root development, curled growth of shoots and agravitropism. Abnormalities observed in the plants that overexpress OsPID could be phenocopied by treatment with an inhibitor of active polar transport of auxin, indicating that OsPID could be involved in the control of polar auxin transport in rice. Analysis of OsPID mRNA distribution showed a complex pattern in shoot meristems, indicating that it ...
Lateral roots originate deep within the parental root from a small number of founder cells at the periphery of vascular tissues and must emerge through intervening layers of tissues. We describe how the hormone auxin, which originates from the developing lateral root, acts as a local inductive signal which re-programmes adjacent cells. Auxin induces the expression of a previously uncharacterized auxin influx carrier LAX3 in cortical and epidermal cells directly overlaying new primordia. Increased LAX3 activity reinforces the auxin-dependent induction of a selection of cell-wall-remodelling enzymes, which are likely to promote cell separation in advance of developing lateral root primordia.. Nature Cell Biology 10 (8), 946-954 ...
Chlorophyta appear to encode at least some of the proteins necessary for auxin biosynthesis and metabolism, which correlates with auxin measurements in members of this division of green algae (Cooke et al., 2002; Lau et al., 2009; Ross and Reid, 2010). On top, putative auxin transport proteins such as AUX1-like and ABCB/PGP-like proteins appear to be present in Chlorophyta, while PIN-like proteins are only encoded in some Streptophyta. While single-celled Chlorophyta seem to possess the potential to transport auxin, at present it is not clear if they import and export auxin from and to the environment, respectively. In the absence of PIN-like auxin carriers, the AUX1-like and ABCB/PGP-like proteins could facilitate putative auxin fluxes in Chlorophyta. While our analyses of S. pratensis and C. orbicularis EST libraries suggest that PIN proteins emerged in the Streptophyta clade, functional data will be required to determine if directional PIN-mediated auxin transport emerged to coordinate ...
Although polar transport and the TIR1-dependent signaling pathway of the plant hormone auxin/indole-3-acetic acid (IAA) are well characterized, understanding of the biosynthetic pathway(s) leading to the production of IAA is still limited. Genetic dissection of IAA biosynthetic pathways has been complicated by the metabolic redundancy caused by the apparent existence of several parallel biosynthetic routes leading to IAA production. Valuable complementary tools for genetic as well as biochemical analysis of auxin biosynthesis would be molecular inhibitors capable of acting in vivo on specific or general components of the pathway(s), which unfortunately have been lacking. Several indole derivatives have been previously identified to inhibit tryptophan-dependent IAA biosynthesis in an in vitro system from maize endosperm. We examined the effect of one of them, 6-fluoroindole, on seedling development of Arabidopsis thaliana and tested its ability to inhibit IAA biosynthesis in feeding experiments ...
The phytohormone auxin regulates diverse aspects of plant development, including tissue elongation, tropic growth, embryogenesis, apical dominance, lateral root initiation, and vascular differentiation (Teale et al., 2006). Proteins in the TRANSPORT INHIBITOR RESPONSE1/AUXIN SIGNALING F-BOX protein (TIR1/AFB) family have recently been demonstrated to function as nuclear receptors for auxin (Dharmasiri et al., 2005a; Kepinski and Leyser, 2005). The auxin signal transduction system operating via the E3 ubiquitin-ligase complex SCFTIR1/AFB (for Skp1-Cul1-F-box protein), which includes TIR1/AFBs, plays a critical role in many auxin-mediated responses through transcriptional regulation (Mockaitis and Estelle, 2008).. Auxin-induced elongation of plant organs, such as hypocotyls, coleoptiles, and roots, has been explained by the acid-growth theory since the 1970s (Rayle and Cleland, 1970; Hager et al., 1971; Moloney et al., 1981). The theory states that auxin enhances proton extrusion via the plasma ...
Auxins are key regulators of plant development. Plants employ a specialized delivery system termed polar auxin transport to convey indole-3-acetic acid from source to target tissues. Auxin transport is mediated by the combined activities of specialized influx and efflux carriers. Mutational approaches in the model plant, Arabidopsis thaliana, have led to the molecular genetic characterization of putative auxin influx and efflux carrier components, AUX1 and AtPIN1. Both genes belong to distinct gene families that are being functionally characterized by using a reverse genetic approach in Arabidopsis. AtPIN proteins are asymmetrically localized within plant plasma membranes, providing a molecular mechanism for the characteristic polarity of auxin transport. We outline the epitope tagging strategy being used in our laboratory to immunolocalize AUX1 and discuss the implications of its subcellular localization for auxin redistribution within root apical tissues. Lastly, we describe a novel ...
Adventitious root (AR) formation in the stem base of cuttings is the basis for propagation of many plant species and petunia is used as model to study this developmental process. Following AR formation from 2 to 192 hours after excision (hpe) of cuttings, transcriptome analysis by microarray revealed a change of the character of the rooting zone from stem base to root identity. The greatest shift in the number of differentially expressed genes was observed between 24 and 72 hpe, when the categories storage, mineral nutrient acquisition, anti-oxidative and secondary metabolism, and biotic stimuli showed a notable high number of induced genes. Analyses of phytohormone-related genes disclosed multifaceted changes of the auxin transport system, auxin conjugation and the auxin signal perception machinery indicating a reduction in auxin sensitivity and phase-specific responses of particular auxin-regulated genes. Genes involved in ethylene biosynthesis and action showed a more uniform pattern as a high number
The plant hormone indoleacetic acid (IAA or auxin) transcriptionally activates a select set of early genes. The Auxl IAA class of early auxin-responsive genes encodes a large family of short-lived, nuclear proteins. Aux/IAA polypeptides homo-and heterodimerize, and interact with auxin-response transcription factors (ARFs) via C-terminal regions conserved in both protein families. This shared region contains a predicted βαα motif similar to the prokaryotic β-Ribbon DNA binding domain, which mediates both protein dimerization and DNA recognition. Here, we show by circular dichroism spectroscopy and by chemical cross-linking experiments that recombinant peptides corresponding to the predicted βαα region of three Aux/IAA proteins from Arabidopsis thaliana contain substantial α-helical secondary structure and undergo homo- and heterotypic interactions in vitro. Our results indicate a similar biochemical function of the plant βαα domain and suggest that the βαα fold plays an important ...
Several recent observations indicated a link between ROP function and PIN endocytosis (Chen et al., 2012; Lin et al., 2012; Nagawa et al., 2012). Our results (Figure 10) show that downregulating ROP signaling or loss of ROP3 function disrupts PIN1 and PIN3 recycling. Together, these results imply that different ROPs could perform distinct functions in the regulation of PIN trafficking, thereby leading to altered PIN polarity and perturbing directional auxin transport. Moreover, our results also show that ROP3 differentially affects auxin transporters, even within the PIN family (Figure 9; Supplemental Figure 8). On the other hand, despite overlapping with AUX1 in its expression domain, ROP3 has no impact on the polarity of AUX1 (Figures 9P to 9R). These data suggest that ROP3 specifically affects the localization of PIN proteins in regions of the root where they coexpress during development.. ROPs are activated by auxin (Tao et al., 2002; Xu et al., 2010) and activated ROPs interact with ...
How did selectivity for the one natural auxin IAA evolve? Are there still novel natural auxins to be discovered? From the structural biology of the auxin receptor TIR1 we have learnt a great deal about how auxin is recognised and how it starts the signalling cascades which alter plant development. Work in our lab has also shown how a different member of the auxin receptor family (AFB5) has a different, wider selectivity profile. An important family of auxin herbicides work through AFB5, and AFB5 is also implicated in the control of branching. This project will explore how and why the receptors have come to differ, and whether there might be a novel plant hormone to be discovered.. Structural biology of auxin transport proteins: a project with Dr Alex Cameron (Life Sciences, Warwick). The goal is to express, purify and determine the structure of auxin transport proteins by crystallography. These transporters determine some of the most profound morphogenic events in biology, such as polarity in ...
p,Ubiquitin-mediated protein degradation is a common feature in diverse plant cell signaling pathways; however, the factors that control the dynamics of regulated protein turnover are largely unknown. One of the best-characterized families of E3 ubiquitin ligases facilitates ubiquitination of auxin (aux)/indole-3-acetic acid (IAA) repressor proteins in the presence of auxin. Rates of auxin-induced degradation vary widely within the Aux/IAA family, and sequences outside of the characterized degron (the minimum region required for auxin-induced degradation) can accelerate or decelerate degradation. We have used synthetic auxin degradation assays in yeast (Saccharomyces cerevisiae) and in plants to characterize motifs flanking the degron that contribute to tuning the dynamics of Aux/IAA degradation. The presence of these rate motifs is conserved in phylogenetically distant members of the Arabidopsis (Arabidopsis thaliana) Aux/IAA family, as well as in their putative Brassica rapa orthologs. We ...
phdthesis{3006170, abstract = {Plants as sessile organisms evolved a specific body structure and at the cellular level mechanisms that allow to survive under extreme environmental conditions. The body shape and subcellular processes are largely dependent on coordinated activity of a small molecule indole-3-acetic acid (IAA), auxin. Local gradients of IAA correlate spatiotemporally with such developmental events like embryogenesis, phyllotaxis, organ initiation or tropisms. Auxin maxima and minima are mostly mediated by auxin efflux carriers PINs. Asymmetric distribution of these proteins determines the directional flow and facilitates the auxin gradient formation. Aberrations in apical or basal auxin-carriers localisation leads to severe developmental defects. Therefore, it is crucial to understand the mechanisms initiating and controlling polar proteins localisation. Next to polarly distributed PINs, there is a growing group of polarly localized proteins transporting hormones or nutrients ...
The export option will allow you to export the current search results of the entered query to a file. Different formats are available for download. To export the items, click on the button corresponding with the preferred download format. By default, clicking on the export buttons will result in a download of the allowed maximum amount of items. To select a subset of the search results, click "Selective Export" button and make a selection of the items you want to export. The amount of items that can be exported at once is similarly restricted as the full export. After making a selection, click one of the export format buttons. The amount of items that will be exported is indicated in the bubble next to export format. ...
Vegetative propagation of economically important woody, horticultural and agricultural species rely on an efficient adventitious root (AR) formation. The formation of ARs is a complex genetic trait regulated by the interaction of environmental and endogenous factors among which the phytohormone auxin plays an essential role. This article summarizes the current knowledge related to the intricate network through which auxin controls adventitious rooting. How auxin and recently identified auxin-related compounds affect AR formation in different plant species is discussed. Particular attention is addressed to illustrate how auxin has a central role in the hormone cross-talk leading to AR development. In parallel, we describe the molecular players involved in the control of auxin homeostasis, transport and signaling, for a better understanding of the auxin action during adventitious rooting. ...
HHMI researchers have identified an enzyme involved in the production of auxin, a plant growth hormone that influences plant growth. Although auxin has been studied for more than 100 years, scientists have not had a good grasp of how the hormone is synthesized by plants
Auxin is involved in many aspects of root development and physiology, including the formation of lateral roots. Improving our understanding of how the auxin response is mediated at the protein level over time can aid in developing a more complete molecular framework of the process. This study evaluates the effects of exogenous auxin treatment on the Arabidopsis root proteome after exposure of young seedlings to auxin for 8, 12, and 24 h, a timeframe permitting the initiation and full maturation of individual lateral roots. Root protein extracts were processed to peptides, fractionated using off-line strong-cation exchange, and analyzed using ultra-performance liquid chromatography and data independent acquisition-based mass spectrometry. Protein abundances were then tabulated using label-free techniques and evaluated for significant changes. Approximately 2000 proteins were identified during the time course experiment, with the number of differences between the treated and control roots increasing over
Plant development is regulated by a number of mobile factors. The Arabidopsis BYPASS1 (BPS1) gene was previously shown to control shoot and root development by preventing formation of a mobile compound, but how this compound functions and whether it modulates other signalling pathways is unclear. Now, Leslie Sieburth and colleagues show that Arabidopsis BPS1, as well as two related genes, BPS2 and BPS3, control the production of a mobile factor, the bps signal, which regulates patterning and growth in parallel with auxin signalling (p. 805). By analysing single, double and triple mutants, the researchers show that all three BPS genes control bps signal synthesis. Importantly, bps triple mutants display severe embryogenesis defects, including disruptions to vascular, root and shoot stem cell populations. Finally, bps triple mutants exhibit normal auxin-induced gene expression and localisation of the PIN1 auxin transporter, suggesting that the bps signal functions in an auxin-independent manner. ...
Sugar regulates a variety of genes and controls plant growth and development similarly to phytohormones. As part of a screen for Arabidopsis mutants with defects in sugar-responsive gene expression, we identified a loss-of-function mutation in the HOOKLESS1 (HLS1) gene. HLS1 was originally identified to regulate apical hook formation of dark-grown seedlings (Lehman et al., 1996, Cell 85: 183-194). In hls1, sugar-induced gene expression in excised leaf petioles was more sensitive to exogenous sucrose than that in the wild type. Exogenous IAA partially repressed sugar-induced gene expression and concomitantly activated some auxin response genes such as AUR3 encoding GH3-like protein. The repression and the induction of gene expression by auxin were attenuated and enhanced, respectively, by the hls1 mutation. These results suggest that HLS1 plays a negative role in sugar and auxin signaling. Because AUR3 GH3-like protein conjugates free IAA to amino acids (Staswick et al., 2002, Plant Cell 14: ...
TY - JOUR. T1 - Bending models of halotropism. T2 - Incorporating protein phosphatase 2A, ABCB transporters, and auxin metabolism. AU - Han, Eun Hyang. AU - Petrella, Dominic P.. AU - Blakeslee, Joshua J.. PY - 2017/6/1. Y1 - 2017/6/1. N2 - Salt stress causes worldwide reductions in agricultural yields, a problem that is exacerbated by the depletion of global freshwater reserves and the use of contaminated or recycled water (i.e. effluent water). Additionally, salt stress can occur as cultivated areas are subjected to frequent rounds of irrigation followed by periods of moderate to severe evapotranspiration, which can result in the heterogeneous aggregation of salts in agricultural soils. Our understanding of the later stages of salt stress and the mechanisms by which salt is transported out of cells and roots has greatly improved over the last decade. The precise mechanisms by which plant roots perceive salt stress and translate this perception into adaptive, directional growth away from ...
PubMed Central Canada (PMC Canada) provides free access to a stable and permanent online digital archive of full-text, peer-reviewed health and life sciences research publications. It builds on PubMed Central (PMC), the U.S. National Institutes of Health (NIH) free digital archive of biomedical and life sciences journal literature and is a member of the broader PMC International (PMCI) network of e-repositories.
The pin-formed mutant pin 1-1, one of the Arabidopsis flower mutants, has several structural abnormalities in inflorescence axes, flowers, and leaves. In some cases, pin1-1 forms a flower with abnormal structure (wide petals, no stamens, pistil-like structure with no ovules in the ovary) at the top of inflorescence axes. In other cases, no floral buds are formed on the axes. An independently isolated allelic mutant (pin1-2) shows similar phenotypes. These mutant phenotypes are exactly the same in wild-type plants cultured in the presence of chemical compounds known as auxin polar transport inhibitors: 9-hydroxyfluorene-9-carboxylic acid or N-(1-naphthyl)phthalamic acid. We tested the polar transport activity of indole-3-acetic acid and the endogenous amount of free indole-3-acetic acid in the tissue of inflorescence axes of the pin1 mutants and wild type. The polar transport activity in the pin 1-1 mutant and in the pin1-2 mutant was decreased to 14% and 7% of wild type, respectively. These ...
Carbon monoxide (CO) and nitric oxide (NO) are essential modulators that regulate the plant response to iron deficiency (-Fe). Auxin is a phytohormone that plays important roles in plant growth and development. We report here that in Arabidopsis -Fe enhanced heme oxygenase-dependent CO generation and auxin transport through redistribution of PIN1 protein, which subsequently increased NO accumulation; NO signaling regulated the activity of ferric chelate reductase (FCR) and the expression of Fe-uptake genes including basic helix-loop-helix transcription factor (FIT) and the ferric reduction oxidase 2 (FRO2). Over-expression of HY1 encoding heme oxygenase, or treatment with CO donor enhanced basipetal auxin transport, FCR activity, and the expressions of FIT and FRO2 under -Fe. Such effects were compromised in the mutant aux1-7 impaired in auxin transport or in the mutant noa1 or nia1/nia2 defective in NO biosynthesis. -Fe failed to promote auxin transport and FCR activity in hy1 mutant; such inability
Auxin is a key signaling molecule for most organogenesis and patterning processes occurring during plant development [50]. The auxin transduction pathway is mainly comprised of two transcriptional regulator families: ARFs and Aux/IAAs [37, 51]. ARFs directly bind to down-stream target genes and regulate their expression during development [52]. ARFs are also involved in the reproduction of various plant species [3, 53]. Characterization and analysis of CpARFs allowed us to reveal the mechanisms behind auxin involvement in fruit and flower development of papaya [54].. In this study, the reference genome sequence of papaya, which is relatively small in size (372 Mbp) [55], was used to identify the complete CpARF family. The number of CpARF genes was less than that in Arabidopsis (23 ARFs) [37]. Protein domain analysis provided us useful information on the biological function of ARFs. A typical ARF contains a DBD, an MR, and a CTD [37]. Aux/IAAs bind to CTDs of ARFs and form heterodimers. The ...
Phylogenetic relationship of Aux/IAA proteins among wheat and another species. The full-length amino-acid sequences of 85 wheat, 31 rice, 29 Arabidopsis, 7 toma
Intercellular transport of auxin is driven by PIN-formed (PIN) proteins. PINs are localized at the plasma membrane (PM) and on constitutively recycling endomembrane vesicles. Therefore, PINs can mediate auxin transport either by direct translocation across the PM or by pumping it into secretory vesicles (SVs), leading to its secretory release upon fusion with the PM. Which of these two mechanisms dominates is a matter of debate. Here we addressed the issue with a mathematical modeling approach. We demonstrate that the efficiency of secretory transport depends on SV size, half-life of PINs on the PM, pH, exocytosis frequency and PIN density. 3D-SIM microscopy was used to determine PIN density on the PM. Combing this data with published values of the other parameters, we show that the transport activity of PINs in SVs would have to be at least 1000x greater than on the PM in order to produce a comparable macroscopic auxin transport. If both transport mechanisms operated simultaneously and PINs were
The Congress President H Ottoline Leyser (Sainsbury Laboratory, University of Cambridge, UK) gave the opening lecture on the regulation of shoot branching and its plasticity in response to ever-changing environmental conditions. The outgrowth of buds is controlled by the interplay between several phytohormones, including auxin, cytokinin and strigolactones. Auxin is transported downwards from the shoot tip and inhibits bud outgrowth, whereas cytokinins, which are produced primarily in roots and transported upward to buds, promote bud outgrowth. Strigolactones, which are produced in roots and shoots and transported to buds to repress bud activity, negatively regulate the activity of auxin efflux carriers called PIN proteins, and reduce the transport of auxin from the shoot tip to buds. Leyser concluded that the downward movement of auxin in the main stem inhibits bud activity by preventing auxin transport out of buds, whereas strigolactones dampen auxin transport and enhance competition between ...
An emerging theme in biology is the importance of cellular signaling dynamics. In addition to monitoring changes in absolute abundance of signaling molecules, many signal transduction pathways are sensitive to changes in temporal properties of signaling components (Purvis and Lahav, 2013). The phytohormone auxin regulates myriad processes in plant development. Many of these require the nuclear auxin signaling pathway, in which degradation of the Aux/IAA repressor proteins allows for transcription of auxin-responsive genes (Korasick et al., 2015). Using a heterologous yeast system, we found that Aux/IAAs exhibit a range of auxin-induced degradation rates when co-expressed in isolation with F-box proteins (Havens et al., 2012). Subsequent studies connecting signaling dynamics to plant growth and development confirmed that Aux/IAAs show similar differences in plants (Guseman et al., 2015; Moss et al., 2015). Here, we describe in detail the use of a heat-shock-inducible fluorescence degradation system to
Plant organs are typically organized into three main tissue layers. The middle ground tissue layer comprises the majority of the plant body and serves a wide range of functions, including photosynthesis, selective nutrient uptake and storage, and gravity sensing. Ground tissue patterning and maintenance in Arabidopsis are controlled by a well-established gene network revolving around the key regulator SHORT-ROOT (SHR). In contrast, it is completely unknown how ground tissue identity is first specified from totipotent precursor cells in the embryo. The plant signaling molecule auxin, acting through AUXIN RESPONSE FACTOR (ARF) transcription factors, is critical for embryo patterning. The auxin effector ARF5/MONOPTEROS (MP) acts both cell-autonomously and noncell-autonomously to control embryonic vascular tissue formation and root initiation, respectively. Here we show that auxin response and ARF activity cell-autonomously control the asymmetric division of the first ground tissue cells. By ...
Plant organs are typically organized into three main tissue layers. The middle ground tissue layer comprises the majority of the plant body and serves a wide range of functions, including photosynthesis, selective nutrient uptake and storage, and gravity sensing. Ground tissue patterning and maintenance in Arabidopsis are controlled by a well-established gene network revolving around the key regulator SHORT-ROOT (SHR). In contrast, it is completely unknown how ground tissue identity is first specified from totipotent precursor cells in the embryo. The plant signaling molecule auxin, acting through AUXIN RESPONSE FACTOR (ARF) transcription factors, is critical for embryo patterning. The auxin effector ARF5/MONOPTEROS (MP) acts both cell-autonomously and noncell-autonomously to control embryonic vascular tissue formation and root initiation, respectively. Here we show that auxin response and ARF activity cell-autonomously control the asymmetric division of the first ground tissue cells. By ...
The present study was undertaken to investigate the plant growth promoting traits of a PGPR P. fluorescens and P. putida like production of Indoleacetic Acid (IAA), side..
TY - JOUR. T1 - A novel auxin conjugate hydrolase from wheat with substrate specificity for longer side-chain auxin amide conjugates. AU - Campanella, James. AU - Olajide, Adebanke F.. AU - Magnus, Volker. AU - Ludwig-Müller, Jutta. PY - 2004/8/1. Y1 - 2004/8/1. N2 - This study investigates how the ILR1-like indole acetic acid (IAA) amidohydrolase family of genes has functionally evolved in the monocotyledonous species wheat (Triticum aestivum). An ortholog for the Arabidopsis IAR3 auxin amidohydrolase gene has been isolated from wheat (TaIAR3). The TaIAR3 protein hydrolyzes negligible levels of IAA-Ala and no other IAA amino acid conjugates tested, unlike its ortholog IAR3. Instead, TaIAR3 has low specificity for the ester conjugates IAA-Glc and IAA-myoinositol and high specificity for the conjugates of indole-3-butyric acid (IBA-Ala and IBA-Gly) and indole-3-propionic-acid (IPA-Ala) so far tested. TaIAR3 did not convert the methyl esters of the IBA conjugates with Ala and Gly. IBA and IBA ...
In higher plants, aerial plant architecture is mainly characterized by the arrangement of leaves and flowers around the stem. Leaves and flowers are formed from the shoot apical meristem (SAM) at well-characterized angles. This pattern of organ development is known as phyllotaxis. A cotyledon is an embryonic leafy organ that is first formed after fertilization, and developed in the apical portion of the embryo from the globular stage onwards. In the case of dicotyledonous plants, the aerial part of the seedling displays bilateral symmetry, as demonstrated by two symmetrically located cotyledons on either side of the SAM. Previous studies have shown that organ positioning is mediated by localized concentrations of the phytohormone auxin during both embryonic and postembryonic development (Benková et al., 2003). Local accumulation of auxin is induced by a directed intercellular transport system from the site of its biosynthesis, referred to as polar auxin transport. In this process, auxin efflux ...
With this PhD project offered within the IMPRS, function analysis of fungal aldehyde dehydrogenases in T. vaccinum is intended, especially both getting a better inside into the IAA biosynthesis in T. vaccinum and investigating IAA transport in ectomycorrhizal fungi. Ethanol detoxification could be proven since overexpressing ald1 mutants showed increased ethanol stress tolerance. In the T. vaccinum genome seven further ald genes could be annotated, which are analyzed by qPCR for induction by chemical triggers like alcohols, aldehydes and biotic signals. To link between systemic reactions of the tree to one or more specific root factors, like mycorrhiza, a volatile collection system was developed, which allows us to characterize changes in the volatile pattern of young coniferous trees ...
PubMed comprises more than 30 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.
Arabidopsis Myrosinase Genes AtTGG4 and AtTGG5 Are Root-Tip Specific and Contribute to Auxin Biosynthesis and Root-Growth Regulation. . Biblioteca virtual para leer y descargar libros, documentos, trabajos y tesis universitarias en PDF. Material universiario, documentación y tareas realizadas por universitarios en nuestra biblioteca. Para descargar gratis y para leer online.
The hormone auxin is transported through many plant tissues with a definite velocity. It is thought that certain channels, or pumps, located at the basal ends of cells, are responsible for the hormones transport. It is also known that auxin will induce veins when applied to suitable tissues. T. Sachs has suggested that it is the flow of the hormone that induces vessels. He suggests that discrete strands form because the transport capacity of a pathway increases with the flux that that pathway carries, leading to a canalization of flow. I cast this in the form of a more specific hypothesis: I suppose the permeability for the transport of auxin through the basal plasmalemma of a cell (by means of whatever kind of pump or channel) to increase with flux. I then show that discrete veins will form provided that the transport permeability increases rapidly enough with flux, and provided that the movement of auxin is not too polar, in the sense that there is a substantial amount of diffusive movement ...
Auxin regulates various aspects of plant growth and development and it also contributes to plant defense. Auxin activates downstream signaling by promoting…
SePRO Corporation has announced the introduction of Cutless Granular, a landscape growth regulator. Cutless Granular is registered with the U.S. EPA for systemic growth suppression of woody ornamental plants and perennial ground covers, resulting in a more compact growth form and reduced need for trimming.. According to SePRO, Cutless Granular contains the active ingredient flurprimido, which interferes with the biosynthesis of gibberellic acid (GA), a plant growth hormone responsible for cell elongation and division. By disrupting GA biosynthesis, cell elongation and division are suppressed, resulting in reduced shoot growth and internode length in landscape ornamentals.. Also according to SePRO, Cutless Granular improves the overall shrub shape and generates fuller more attractive plants by stimulating branching and promoting darker green foliage. Plants treated with Cutless Granular will require less trimming and will reduce annual labor costs for maintaining landscaped shrubs, hedges and ...
Brief irradiation of 3-d-old maize (Zea mays L.) seedlings with red light (R; 180 J m(-2)) inhibits elongation of the mesocotyl (70-80% inhibition in 8 h) and reduces its indole-3-acetic acid (IAA) content. The reduction in IAA content, apparent within a few hours, is the result of a reduction in ...
Currently, my work is focused on two projects. The first project deals with the the identification of genetic suppressors of tir-1-1 mediated auxin resistance. In my second project I am studying natural variation in transcriptional auxin responses. Additional interests comprise the natural variation of responses jasmonates and other oxylipins. ...
Hamann et al. (1999) ,, The auxin-insensitive bodenlos mutation affects primary root formation and apical-basal patterning in the Arabidopsis embryo ,,[http://www.ncbi.nlm.nih.gov/pubmed/10068632 Development 126: 1387-1395 abstract] ,, Tom, Franziska W ...
E.J.Woo, J.Marshall, J.Bauly, J.-G.Chen, M.Venis, R.M.Napier, R.W.Pickersgill Crystal Structure Of Auxin-Binding Protein 1 In Complex With Auxin Embo J. V. 21 2877 ...
Shoots are positively phototropic. When a shoot tip is exposed to light, it accumulates more auxin on the side thats in the shade than the side thats in the light. This makes the cells elongate faster, shaded side, so the shoot goes towards light. ...
SCATCHARD PLOT- plots data on binding of hormone to receptor to determine the dissociation constant for the hormone to the binding molecule. Particularly useful to determine whether one or more binding molecules are present in the solution being tested. If two molecules bind hormone are present, the plot is not linear. This shows the importance of obtaining binding data to a number of concentrations of added hormone. To eliminate complications due to molecules that do not bind specifically, but rather bind irreversibly, at each concentration of radiolabeled hormone added, free cold hormone is added, and the bound-radiolabeled hormone is again quantified. The amount of hormone still bound after this chase is the amount of irreversible ( non-specific ) binding. ...
Learn more about indol-3-ylacetonitrile. We enable science by offering product choice, services, process excellence and our people make it happen.
10-Methoxy-6-methyl-1,2,3,4,5,6-hexahydroazepino[4,5-b]indol-6-iumchloride/ACM15923430 can be provided in Alfa Chemistry. We are dedicated to provide our customers the best products and services.