| hemoglobin genes in non-legumes: cloning and characterization of a casuarina glauca hemoglobin gene. | | 1991 | 1893106 |
| symbiotic and nonsymbiotic hemoglobin genes of casuarina glauca. | casuarina glauca has a gene encoding hemoglobin (cashb-nonsym). this gene is expressed in a number of plant tissues. casuarina also has a second family of hemoglobin genes (cashb-sym) expressed at a high level in the nodules that casuarina forms in a nitrogen-fixing symbiosis with the actinomycete frankia. both the nonsymbiotic and symbiotic genes retained their specific patterns of expression when introduced into the legume lotus corniculatus. we interpret this finding to mean that the controls ... | 1995 | 7756831 |
| hairy root nodulation of casuarina glauca: a system for the study of symbiotic gene expression in an actinorhizal tree. | the purpose of this study was to establish a fast system for producing transgenic actinorhizal root nodules of casuarina glauca. agrobacterium rhizogenes strain a4rs carrying the p35s-gusa-int gene construct was used to induce hairy roots on hypocotyls of 3-week-old c. glauca seedlings. three weeks after wounding, the original root system was excised, and composite plants consisting of transgenic roots on untransformed shoots were transferred to test tubes to be inoculated with frankia. the acti ... | 1995 | 8589409 |
| cell-specific expression of the promoters of two nonlegume hemoglobin genes in a transgenic legume, lotus corniculatus. | the promoters of the hemoglobin genes from the nitrogen-fixing tree parasponia andersonii and the related nonnitrogen-fixing trema tomentosa both confer beta-glucuronidase reporter gene expression to the central zone of the nodules of a transgenic legume, lotus corniculatus. beta-glucuronidase expression was high in the uninfected interstitial cells and parenchyma of the surrounding boundary layer and was low in the rhizobium-infected cells. this contrasts with the expression of both the p. ande ... | 1997 | 9008386 |
| flavan-containing cells delimit frankia-infected compartments in casuarina glauca nodules. | we investigated the involvement of polyphenols in the casuarina glauca-frankia symbiosis. histological analysis revealed a cell-specific accumulation of phenolics in c. glauca nodule lobes, creating a compartmentation in the cortex. histochemical and biochemical analyses indicated that these phenolic compounds belong to the flavan class of flavonoids. we show that the same compounds were synthesized in nodules and uninfected roots. however, the amount of each flavan was dramatically increased in ... | 1999 | 10482666 |
| casuarina glauca prenodule cells display the same differentiation as the corresponding nodule cells. | recent phylogenetic studies have implied that all plants able to enter root nodule symbioses with nitrogen-fixing bacteria go back to a common ancestor (d.e. soltis, p.s. soltis, d.r. morgan, s.m. swensen, b.c. mullin, j.m. dowd, and p.g. martin, proc. natl. acad. sci. usa, 92:2647-2651, 1995). however, nodules formed by plants from different groups are distinct in nodule organogenesis and structure. in most groups, nodule organogenesis involves the induction of cortical cell divisions. in legum ... | 2000 | 10656591 |
| characterization of a casuarina glauca nodule-specific subtilisin-like protease gene, a homolog of alnus glutinosa ag12. | in search of plant genes expressed during early interactions between casuarina glauca and frankia, we have isolated and characterized a c. glauca gene that has strong homology to subtilisin-like protease gene families of several plants including the actinorhizal nodulin gene ag12 of another actinorhizal plant, alnus glutinosa. based on the expression pattern of cg12 in the course of nodule development, it represents an early actinorhizal nodulin gene. our results suggest that subtilisin-like pro ... | 2000 | 10656592 |
| symbiotic and non-symbiotic expression of cgmt1, a metallothionein-like gene from the actinorhizal tree casuarina glauca. | a clone for a type 1 metallothionein (cgmt1) was isolated from a casuarina glauca nodule cdna library. the corresponding gene belongs to a small family and is highly expressed in roots and nitrogen-fixing nodules, whereas low expression was observed in aerial parts of the plant. the promoter region of cgmt1 was isolated and fused to the beta-glucuronidase (gus) gene. transgenic casuarinaceae plants showed that the cgmt1 promoter was most active in roots and in the oldest region of the shoot. in ... | 2002 | 12008901 |
| can the nitrogenous composition of xylem sap be used to assess salinity stress in casuarina glauca? | it is predicted that dryland salinity will affect up to 17 mha of the australian landscape by 2050, and therefore, monitoring the health of tree plantings and remnant native vegetation in saline areas is increasingly important. casuarina glauca sieber ex spreng. has considerable salinity tolerance and is commonly planted in areas with a shallow, saline water table. to evaluate the potential of using the nitrogenous composition of xylem sap to assess salinity stress in c. glauca, the responses of ... | 2002 | 12359529 |
| the promoter of a metallothionein-like gene from the tropical tree casuarina glauca is active in both annual dicotyledonous and monocotyledonous plants. | a chimeric gene consisting of the beta-glucuronidase (gusa) reporter gene under the control of the metallothionein-like promoter cgmt1 from the tropical tree casuarina glauca was introduced into nicotiana tabacum via agrobacterium tumefaciens and into oryza sativa by particle bombardment. the strongest histochemical staining for gus activity was observed in the root system of the transgenic plants, and especially in lateral roots. in contrast, a relatively low level of reporter gene expression w ... | 2003 | 12779116 |
| cg12 expression is specifically linked to infection of root hairs and cortical cells during casuarina glauca and allocasuarina verticillata actinorhizal nodule development. | cg12 is an early actinorhizal nodulin gene from casuarina glauca encoding a subtilisin-like serine protease. using transgenic casuarinaceae plants carrying cg12-gus and cg12-gfp fusions, we have studied the expression pattern conferred by the cg12 promoter region after inoculation with frankia. cg12 was found to be expressed in root hairs and in root and nodule cortical cells containing frankia infection threads. cg12 expression was also monitored after inoculation with ineffective frankia strai ... | 2003 | 12848425 |
| relative importance of the endomycorrhizal and (or) ectomycorrhizal associations in allocasuarina and casuarina genera. | this work was carried out to determine the relative importance of the endomycorrhizal and (or) ectomycorrhizal association in species of casuarina and allocasuarina. under axenic conditions, pisolithus and scleroderma isolates formed ectomycorrhizas with a mantle and a hartig net on allocasuarina verticillata but failed to form a hartig net on casuarina glauca. in a controlled soil system, c. glauca was inoculated with the endomycorrhizal fungus glomus intraradices schenck & smith, and a. vertic ... | 2003 | 12897837 |
| does ethylene mediate cluster root formation under iron deficiency? | casuarina glauca develops proteoid (cluster) roots in response to fe deficiency. this study set out to investigate the possible involvement of ethylene in the initiation and/or the morphogenesis of cluster roots (cr). for this purpose, the effect of ag+ added as silver thiosulfate, an inhibitor of ethylene action has been studied in plants growing hydroponically. no cr formation was observed in these growth conditions. inhibition of ethylene biosynthesis by aminoethoxyvinylglycine, 1- aminoisobu ... | 2003 | 12967908 |
| comparison of nodule induction in legume and actinorhizal symbioses: the induction of actinorhizal nodules does not involve enod40. | two types of root nodule symbioses are known for higher plants, legume and actinorhizal symbioses. in legume symbioses, bacterial signal factors induce the expression of enod40 genes. we isolated an enod40 promoter from an actinorhizal plant, casuarina glauca, and compared its expression pattern in a legume (lotus japonicus) and an actinorhizal plant (allocasuarina verticillata) with that of an enod40 promoter from the legume soybean (gmenod40-2). in the actinorhizal allocasuarina sp., cgenod40- ... | 2003 | 12971604 |
| infection-related activation of the cg12 promoter is conserved between actinorhizal and legume-rhizobia root nodule symbiosis. | two nitrogen-fixing root nodule symbioses between soil bacteria and higher plants have been described: the symbiosis between legume and rhizobia and actinorhizal symbioses between plants belonging to eight angiosperm families and the actinomycete frankia. we have recently shown that the subtilisin-like ser protease gene cg12 (isolated from the actinorhizal plant casuarina glauca) is specifically expressed during plant cell infection by frankia. here we report on the study of c. glauca cg12 promo ... | 2004 | 15466224 |
| growth and productivity assessment of casuarina glauca sieb. ex. spreng on sodic soil sites. | casuarina glauca is an introduced tree species to india. it is one the few species that can grow successfully in salt effected sites. c. glauca was investigated for biomass production at highly sodic soil sites (ph 8.6-10.5); it was found to be promising in terms of growth and productivity. average height of plants in an 8-yr-old trial of casuarina glauca was 1033.3+/-270 cm, however diameter at breast height (dbh) remained at 8.59+/-2.0 cm with a basal area of 6.68+/-1.6 cm2 per plant. high pla ... | 2005 | 15792588 |
| aerial nodules in casuarina cunninghamiana. | a complete survey of la réunion island showed that, in 40- to 50-year-old casuarina cunninghamiana plantations located in the northeast at an altitude above 400 m, some trees bore aerial nodules as high as 6 to 7 m up the trunk. the nodules exhibited a significant specific acetylene reduction by the ara method (0.77 mumol of c(2)h(4) per h/g [dry weight] of nodule) at the time of sampling (june 1990). aerial nodules were also found on a casuarina glauca trunk. preliminary observations show that ... | 1991 | 16348452 |
| expressed sequence-tag analysis in casuarina glauca actinorhizal nodule and root. | the present study aimed to identify and assess the frequency and tissue specificity of plant genes in the actinorhizal casuarina glauca-frankia symbiosis through expressed sequence tag (est) analysis. using a custom analysis pipeline for raw sequences of c. glauca uninfected roots and nodules, we obtained an est databank web interface. gene expression was studied in nodules vs roots using comparative quantitative real-time reverse transcription-polymerase chain reaction (qrt-pcr). from roots and ... | 2006 | 16441749 |
| a class 1 hemoglobin gene from alnus firma functions in symbiotic and nonsymbiotic tissues to detoxify nitric oxide. | actinorhizal symbiosis is as important in biological nitrogen fixation as legume-rhizobium symbiosis in the global nitrogen cycle. to understand the function of hemoglobin (hb) in actinorhizal symbiosis, we characterized a hb of alnus firma, afhb1. a cdna that encodes nonsymbiotic hb (nonsym-hb) was isolated from a cdna library of a. firma nodules probed with ljhb1, a nonsym-hb of lotus japonicus. no homolog of symbiotic hb (sym-hb) could be identified by screening in the cdna library or by poly ... | 2006 | 16610747 |
| a single hemoglobin gene in myrica gale retains both symbiotic and non-symbiotic specificity. | here, a hemoglobin gene from the nitrogen-fixing actinorhizal plant myrica gale was isolated, cloned and sequenced. the gene (mghb) was a class i hemoglobin with strong sequence homology to non-symbiotic hemoglobin genes. mghb is highly expressed in symbiotic root nodules, but transcripts and protein were also detected in leaves of m. gale. in arabidopsis thaliana the mghb promoter, linked to a beta-glucuronidase coding region, directed expression in the vascular tissue, in shoot meristem and at ... | 2006 | 16897491 |
| auxin influx activity is associated with frankia infection during actinorhizal nodule formation in casuarina glauca. | plants from the casuarinaceae family enter symbiosis with the actinomycete frankia leading to the formation of nitrogen-fixing root nodules. we observed that application of the auxin influx inhibitor 1-naphtoxyacetic acid perturbs actinorhizal nodule formation. this suggests a potential role for auxin influx carriers in the infection process. we therefore isolated and characterized homologs of the auxin influx carrier (aux1-lax) genes in casuarina glauca. two members of this family were found to ... | 2007 | 17556507 |
| functional analysis of the metallothionein gene cgmt1 isolated from the actinorhizal tree casuarina glauca. | cgmt1 is a metallothionein (mt)-like gene that was isolated from a cdna library of young nitrogen-fixing nodules resulting from the symbiotic interaction between frankia spp. and the actinorhizal tree casuarina glauca. cgmt1 is highly transcribed in the lateral roots and nitrogen-fixing cells of actinorhizal nodules; it encodes a class i type 1 mt. to obtain insight into the function of cgmt1, we studied factors regulating the expression of the mt promoter region (pcgmt1) using a beta-glucuronid ... | 2007 | 17918625 |
| retranslocation of foliar nutrients in evergreen tree species planted in a mediterranean environment. | internal nutrient recycling through retranslocation (resorption) is important for meeting the nutrient demands of new tissue production in trees. we conducted a comparative study of nutrient retranslocation from leaves of five tree species from three genera grown in plantation forests for commercial or environmental purposes in southern australia--acacia mearnsii de wild., eucalyptus globulus labill., e. fraxinoides h. deane & maiden, e. grandis w. hill ex maiden and pinus radiata d. don. signif ... | 2008 | 18055429 |
| symrk defines a common genetic basis for plant root endosymbioses with arbuscular mycorrhiza fungi, rhizobia, and frankiabacteria. | root endosymbioses vitally contribute to plant nutrition and fitness worldwide. nitrogen-fixing root nodulation, confined to four plant orders, encompasses two distinct types of associations, the interaction of legumes (fabales) with rhizobia bacteria and actinorhizal symbioses, where the bacterial symbionts are actinomycetes of the genus frankia. although several genetic components of the host-symbiont interaction have been identified in legumes, the genetic basis of actinorhiza formation is un ... | 2008 | 18316735 |
| molecular evidence of hybridization in florida's sheoak (casuarina spp.) invasion. | the presence of hybrids in plant invasions can indicate a potential for rapid adaptation and an added level of complexity in management of the invasion. three casuarina tree species, casuarina glauca, casuarina cunninghamiana and casuarina equisetifolia, native to australia, are naturalized in florida, usa. many florida casuarina trees are considered unidentifiable, presumably due to interspecific hybridization. we collected tissue from over 500 trees from australia and florida and genotyped the ... | 2009 | 19627489 |
| diminished exoproteome of frankia spp. in culture and symbiosis. | frankia species are the most geographically widespread gram-positive plant symbionts, carrying out n(2) fixation in root nodules of trees and woody shrubs called actinorhizal plants. taking advantage of the sequencing of three frankia genomes, proteomics techniques were used to investigate the population of extracellular proteins (the exoproteome) from frankia, some of which potentially mediate host-microbe interactions. initial two-dimensional sodium dodecyl sulfate-polyacrylamide gel electroph ... | 2009 | 19749056 |
| infection-specific activation of the medicago truncatula enod11 early nodulin gene promoter during actinorhizal root nodulation. | the mtenod11 gene from medicago truncatula is widely used as an early infection-related molecular marker for endosymbiotic associations involving both rhizobia and arbuscular mycorrhizal fungi. in this article, heterologous expression of the mtenod11 promoter has been studied in two actinorhizal trees, casuarina glauca and allocasuarina verticillata. transgenic c. glauca and a. verticillata expressing a promtenod11::beta-glucuronidase (gus) fusion were generated and the activation of the transge ... | 2010 | 20459313 |
| auxin carriers localization drives auxin accumulation in plant cells infected by frankia in casuarina glauca actinorhizal nodules. | actinorhizal symbioses are mutualistic interactions between plants and the soil bacteria frankia that lead to the formation of nitrogen-fixing root nodules. little is known about the signaling mechanisms controlling the different steps of the establishment of the symbiosis. the plant hormone auxin has been suggested to play a role. here we report that auxin accumulates within frankia-infected cells in actinorhizal nodules of casuarina glauca. using a combination of computational modeling and exp ... | 2010 | 20826704 |
| transcriptomics of actinorhizal symbioses reveals homologs of the whole common symbiotic signaling cascade. | comparative transcriptomics of two actinorhizal symbiotic plants, casuarina glauca and alnus glutinosa, was used to gain insight into their symbiotic programs triggered following contact with the nitrogen-fixing actinobacterium frankia. approximately 14,000 unigenes were recovered in roots and 3-week-old nodules of each of the two species. a transcriptomic array was designed to monitor changes in expression levels between roots and nodules, enabling the identification of up- and down-regulated g ... | 2011 | 21464474 |
| response of root branching to abscisic acid is correlated with nodule formation both in legumes and nonlegumes. | legumes are unique among higher plants in forming a symbiosis with rhizobium. phylogenetic studies indicate this symbiosis may have evolved as many as three times within the fabaceae; alternatively, a predisposition for nodulation evolved early in the history of the legume lineage. we have identified a physiological trait-increased lateral root formation in response to abscisic acid (aba)- that marks all nodulating and non-nodulating legume species in our study set with the exception of chamaecr ... | 2005 | 21646084 |
| Analysis of the subcellular localisation of lipoxygenase in legume and actinorhizal nodules. | Plant lipoxygenases (LOXs; EC 1.13.11.12) catalyse the oxygenation of polyunsaturated fatty acids, linoleic (18:2) and a-linolenic acid (18:3(n-3)) and are involved in processes such as stress responses and development. Depending on the regio-specificity of a LOX, the incorporation of molecular oxygen leads to formation of 9- or 13-fatty acid hydroperoxides, which are used by LOX itself as well as by members of at least six different enzyme families to form a series of biologically active molecu ... | 2012 | 21973171 |