scholarly journals Identification of Arbuscular Mycorrhiza Fungi Responsive microRNAs and Their Regulatory Network in Maize

2018 ◽  
Vol 19 (10) ◽  
pp. 3201 ◽  
Author(s):  
Yunjian Xu ◽  
Suwen Zhu ◽  
Fang Liu ◽  
Wei Wang ◽  
Xuewen Wang ◽  
...  
Keyword(s):  
Arbuscular Mycorrhiza ◽  
High Throughput Sequencing ◽  
Glomus Intraradices ◽  
Target Genes ◽  
Am Fungi ◽  
Symbiotic Relationships ◽  
Network Analyses ◽  
Phosphate Starvation Response ◽  
Am Fungus ◽  
Am Symbiosis

Maize can form symbiotic relationships with arbuscular mycorrhiza (AM) fungus to increase productivity and resistance, but the miRNAs in maize responsible for this process have not been discovered. In this study, 155 known and 28 novel miRNAs were identified by performing high-throughput sequencing of sRNA in maize roots colonized by AM fungi. Similar to the profiles in other AM-capable plants, a large proportion of identified maize miRNAs were 24 nt in length. Fourteen and two miRNAs were significantly down- and up-regulated in response to AM fungus Glomus intraradices inoculation, respectively, suggesting potential roles of these miRNAs in AM symbiosis. Interestingly, 12 of 14 significantly down-regulated known maize miRNAs belong to the miR399 family, which was previously reported to be involved in the interaction between Medicago truncatula and AM fungi. This result indicated that the miR399 family should regulate AM symbiosis conservatively across different plant lineages. Pathway and network analyses showed that the differentially expressed miRNAs might regulate lipid metabolism and phosphate starvation response in maize during the symbiosis process via their target genes. Several members of the miR399 family and the miR397 family should be involved in controlling the fatty acid metabolism and promoting lipid delivering from plants to AM fungi. To the best of our knowledge, this is the first report on miRNAs mediating fatty acids from plant to AM fungi. This study provides insight into the regulatory roles of miRNAs in the symbiosis between plants and AM fungi.

scholarly journals Target of rapamycin, PvTOR, is a key regulator of arbuscule development during mycorrhizal symbiosis in Phaseolus

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Manoj-Kumar Arthikala ◽  
Kalpana Nanjareddy ◽  
Lourdes Blanco ◽  
Xóchitl Alvarado-Affantranger ◽  
Miguel Lara
Keyword(s):  
Arbuscular Mycorrhizal ◽  
Am Fungi ◽  
Target Of Rapamycin ◽  
Mycorrhizal Symbiosis ◽  
Energy Status ◽  
Symbiotic Associations ◽  
Expression Of Genes ◽  
Fungal Symbiosis ◽  
Am Fungus ◽  
Am Symbiosis

AbstractTarget of rapamycin (TOR) is a conserved central growth regulator in eukaryotes that has a key role in maintaining cellular nutrient and energy status. Arbuscular mycorrhizal (AM) fungi are mutualistic symbionts that assist the plant in increasing nutrient absorption from the rhizosphere. However, the role of legume TOR in AM fungal symbiosis development has not been investigated. In this study, we examined the function of legume TOR in the development and formation of AM fungal symbiosis. RNA-interference-mediated knockdown of TOR transcripts in common bean (Phaseolus vulgaris) hairy roots notably suppressed AM fungus-induced lateral root formation by altering the expression of root meristem regulatory genes, i.e., UPB1, RGFs, and sulfur assimilation and S-phase genes. Mycorrhized PvTOR-knockdown roots had significantly more extraradical hyphae and hyphopodia than the control (empty vector) roots. Strong promoter activity of PvTOR was observed at the site of hyphal penetration and colonization. Colonization along the root length was affected in mycorrhized PvTOR-knockdown roots and the arbuscules were stunted. Furthermore, the expression of genes induced by AM symbiosis such as SWEET1, VPY, VAMP713, and STR was repressed under mycorrhized conditions in PvTOR-knockdown roots. Based on these observations, we conclude that PvTOR is a key player in regulating arbuscule development during AM symbiosis in P. vulgaris. These results provide insight into legume TOR as a potential regulatory factor influencing the symbiotic associations of P. vulgaris and other legumes.

scholarly journals Lipo-chitooligosaccharide Signaling in Endosymbiotic Plant-Microbe Interactions

2011 ◽  
Vol 24 (8) ◽  
pp. 867-878 ◽  
Author(s):  
Clare Gough ◽  
Julie Cullimore
Keyword(s):  
Glomus Intraradices ◽  
Mutual Recognition ◽  
Arbuscular Mycorrhizal ◽  
Defense Responses ◽  
Fungal Cell ◽  
Root Branching ◽  
Bacterial Endosymbionts ◽  
Microbe Interactions ◽  
Am Fungus ◽  
Am Symbiosis

The arbuscular mycorrhizal (AM) and the rhizobia-legume (RL) root endosymbioses are established as a result of signal exchange in which there is mutual recognition of diffusible signals produced by plant and microbial partners. It was discovered 20 years ago that the key symbiotic signals produced by rhizobial bacteria are lipo-chitooligosaccharides (LCO), called Nod factors. These LCO are perceived via lysin-motif (LysM) receptors and activate a signaling pathway called the common symbiotic pathway (CSP), which controls both the RL and the AM symbioses. Recent work has established that an AM fungus, Glomus intraradices, also produces LCO that activate the CSP, leading to induction of gene expression and root branching in Medicago truncatula. These Myc-LCO also stimulate mycorrhization in diverse plants. In addition, work on the nonlegume Parasponia andersonii has shown that a LysM receptor is required for both successful mycorrhization and nodulation. Together these studies show that structurally related signals and the LysM receptor family are key components of both nodulation and mycorrhization. LysM receptors are also involved in the perception of chitooligosaccharides (CO), which are derived from fungal cell walls and elicit defense responses and resistance to pathogens in diverse plants. The discovery of Myc-LCO and a LysM receptor required for the AM symbiosis, therefore, not only raises questions of how legume plants discriminate fungal and bacterial endosymbionts but also, more generally, of how plants discriminate endosymbionts from pathogenic microorganisms using structurally related LCO and CO signals and of how these perception mechanisms have evolved.

Arbuscular mycorrhiza and nitrification: Competition for free ammonium ions?

2021 ◽  
Author(s):  
Jan Jansa ◽  
Michala Kotianová ◽  
Kateřina Gančarčíková ◽  
Martin Rozmoš ◽  
Hana Hršelová ◽  
...  
Keyword(s):  
Arbuscular Mycorrhiza ◽  
Am Fungi ◽  
Plant Litter ◽  
Organic N ◽  
Nitrification Inhibitors ◽  
Ammonia Oxidizers ◽  
Plant Host ◽  
Total N ◽  
Am Symbiosis ◽  
Mycorrhizal Plants

<p>Arbuscular mycorrhiza (AM) is ancient and widespread inter-kingdom symbiotic relationship being established by a majority of terrestrial plant species and specialized fungi, which interconnect plant roots with surrounding soil. By doing so, this symbiosis can greatly increase acquisition of multiple mineral nutrients such as phosphorus, nitrogen (N), and copper by the plants from the soil, in exchange for reduced carbon supplied by the plant host. Supposedly, this is mainly due to extending the soil volume accessible for nutrient acquisition by the fungal hyphae compared to roots alone. Both the plants and the AM fungi require N for construction of their bodies. This can potentially result in different effects of AM symbiosis establishment on plant N nutrition ranging from positive to negative. Yet, the demand for and efficiency of mineral N uptake from the soil by a mycorrhizal plant is usually higher than that of a nonmycorrhizal plant. This may exert important feedbacks of AM symbiosis on soil processes in general and N cycling in particular. Here we asked what role does the symbiosis play in acquisition of N by a model plant, Andropogon gerardii, from an organic source (i.e., plant litter labeled with 15N) supplied in a soil zone beyond the direct reach of roots. Further, we tested whether this process of N acquisition by plant from the soil via mycorrhizal hyphae could be affected by supplying various synthetic nitrification inhibitors (DCD, nitrapyrin, or DMPP) along with the litter. We observed efficient acquisition of N to mycorrhizal plants via mycorrhizal pathway irrespective of the nitrification inhibitor supplied or not along with the plant litter. These results were strongly contrasting with 15N uptake (but not total N content of the plants or the plant biomass) of the nonmycorrhizal plants, which generally received much less 15N than the mycorrhizal plants, and this was further suppressed by nitrapyrin or DMPP supplementation of the organic N source as compared to DCD or the control (i.e., no inhibitor) treatment. Quantitative real-time PCR analyses of the microbial communities indicated that microbes involved in the rate-limiting step of nitrification, i.e., the ammonia oxidizers, were suppressed similarly by AM fungi as they were by nitrapyrin or DMPP amendments. These results suggest that mycorrhizal fungi successfully outcompeted the prokaryotic ammonia oxidizers, and this was most likely by accessing and efficiently utilizing/removing free ammonia ion pool in/from the soil via their extensive hyphal networks.</p>

scholarly journals Sugar transporters of the SWEET family and their role in arbuscular mycorrhiza

2021 ◽  
Vol 25 (7) ◽  
pp. 754-760
Author(s):  
A. A. Kryukov ◽  
A. O. Gorbunova ◽  
T. R. Kudriashova ◽  
O. I. Yakhin ◽  
A. A. Lubyanov ◽  
...  
Keyword(s):  
Arbuscular Mycorrhiza ◽  
Abiotic Stress Tolerance ◽  
Carbon Assimilation ◽  
Substantial Part ◽  
Special Role ◽  
Transport Pathways ◽  
Sugar Transporters ◽  
Symbiotic Relationships ◽  
Sweet Proteins ◽  
Am Symbiosis

Plant sugar transporters play an essential role in the organism’s productivity by carrying out carbohydrate transportation from source cells in the leaves to sink cells in the cortex. In addition, they aid in the regulation of a substantial part of the exchange of nutrients with microorganisms in the rhizosphere (bacteria and fungi), an activity essential to the formation of symbiotic relationships. This review pays special attention to carbohydrate nutrition during the development of arbuscular mycorrhiza (AM), a symbiosis of plants with fungi from the Glomeromycotina subdivision. This relationship results in the host plant receiving micronutrients from the mycosymbiont, mainly phosphorus, and the fungus receiving carbon assimilation products in return. While the efficient nutrient transport pathways in AM symbiosis are yet to be discovered, SWEET sugar transporters are one of the three key families of plant carbohydrate transporters. Specific AM symbiosis transporters can be identified among the SWEET proteins. The survey provides data on the study history, structure and localization, phylogeny and functions of the SWEET proteins. A high variability of both the SWEET proteins themselves and their functions is noted along with the fact that the same proteins may perform different functions in different plants. A special role is given to the SWEET transporters in AM development. SWEET transporters can also play a key role in abiotic stress tolerance, thus allowing plants to adapt to adverse environmental conditions. The development of knowledge about symbiotic systems will contribute to the creation of microbial preparations for use in agriculture in the Russian Federation. 

scholarly journals Molecular signal communication during arbuscular mycorrhizal formation induces significant transcriptional reprogramming of wheat (Triticum aestivum) roots

2019 ◽  
Author(s):  
Hui Tian ◽  
Runze Wang ◽  
Mengjiao Li ◽  
Haiyan Dang ◽  
Zakaria M Solaiman
Keyword(s):  
High Throughput Sequencing ◽  
Arbuscular Mycorrhizal ◽  
Am Fungi ◽  
Physical Contact ◽  
Nitrogen And Phosphorus ◽  
Wheat Roots ◽  
Transcriptional Profiles ◽  
Am Symbiosis ◽  
Molecular Signal ◽  
Pass Through

Abstract Background and Aims Arbuscular mycorrhizal (AM) symbiosis begins with molecular signal communication (MSC) between AM fungi and the roots of the host plant. We aimed to test the hypothesis that the transcriptional profiles of wheat roots can be changed significantly by AM symbiotic signals, without direct contact. Methods Non-mycorrhizal (NM) and MSC treatments involved burying filter membrane bags containing sterilized and un-sterilized inoculum of the AM fungus Rhizophagus irregularis, respectively. The bags physically separated roots and AM structures but allowed molecular signals to pass through. Extracted RNA from wheat roots was sequenced by high-throughput sequencing. Results Shoot total nitrogen and phosphorus content of wheat plants was decreased by the MSC treatment. A total of 2360 differentially expressed genes (DEGs), including 1888 up-regulated DEGs and 472 down-regulated DEGs, were found dominantly distributed on chromosomes 2A, 2B, 2D, 3B, 5B and 5D. The expression of 59 and 121 genes was greatly up- and down-regulated, respectively. Only a portion of DEGs could be enriched into known terms during gene ontology analysis, and were mostly annotated to ‘catalytic activity’, ‘protein metabolic process’ and ‘membrane’ in the molecular function, biological process and cellular component ontology categories, respectively. More than 120 genes that may be involved in key processes during AM symbiosis development were regulated at the pre-physical contact stages. Conclusions The transcriptional profiles of wheat roots can be changed dramatically by MSC. Much of the information provided by our study is of great importance for understanding the mechanisms underlying the development of AM symbiosis.

scholarly journals Arbuscular mycorrhiza of plants from the Mountain Botanical Garden in Zakopane

2014 ◽  
Vol 40 (1) ◽  
pp. 25-41 ◽  
Author(s):  
Szymon Zubek ◽  
Katarzyna Turnau ◽  
Janusz Błaszkowski
Keyword(s):  
Arbuscular Mycorrhiza ◽  
Threatened Species ◽  
Am Fungi ◽  
Botanical Garden ◽  
Glomus Aggregatum ◽  
Tatra Mts ◽  
Am Symbiosis ◽  
Academy Of Sciences ◽  
Rare Endemic ◽  
First Time

The mycorrhizal status of 77 plant species collected from the Mountain Botanical Garden of the Polish Academy of Sciences in Zakopane (southern Poland) was surveyed. These plants include rare, endemic and threatened species in the Tatra Mts. (the Western Carpathians) and are maintained in the botanical garden in order to develop effective methods of protection and cultivation. Plants belonging to <i>Brassicaceae, Caryophyllaceae, Dryopteridaceae, Juncaceae, Polygonaceae, Rubiaceae</i> and <i>Woodsiaceae</i> families were nonmycorrhizal. 41 species formed AM symbiosis. Spores of nine AMF spccies (<i>Glomeromycota</i>), including <i>Archaeospora trappei, Glomus aggregatum, G. claroideum, G. constrictum, G. deserticola, G. geosponrum, G. microcarpum, G. mosseae</i> and <i>G.rubiforme</i> were isolated for the first time from this region of Poland. In addition, the occurrence of the fine endophyte, <i>G. tenue</i> was detected in roots of 18 species from the study area, although formation of arbuscules by this fungus was observed rarely. AM fungi were sporadically accompanied by dark septate endophytes (DSE). 70% of nonmycorrhizal plant sepcies were devoid of DSE.

Genetic supressors of Lotus japonicus har1-1 hypernodulation show altered interactions with Glomus intraradices

2006 ◽  
Vol 33 (8) ◽  
pp. 749 ◽  
Author(s):  
Jeremy Murray ◽  
Ryan Geil ◽  
Cameron Wagg ◽  
Bogumil Karas ◽  
Krzysztof Szczyglowski ◽  
...  
Keyword(s):  
Glomus Intraradices ◽  
Lotus Japonicus ◽  
Arbuscular Mycorrhizal ◽  
Am Fungi ◽  
Parental Line ◽  
Cortical Cells ◽  
Root Colonisation ◽  
Genetic Suppressors ◽  
Am Fungus ◽  
Mutant Lines

Mutant lines of Lotus japonicus (Regel) Larsen that show defects in nodulation as well as in mycorrhiza formation are valuable resources for studying the events required for the establishment of functional symbioses. In this study, 11 mutant lines derived from a screen for genetic suppressors of har1-1 hypernodulation were assessed quantitatively for their ability to form arbuscular mycorrhizal (AM) symbiosis. The presence of extraradical mycelia, appressoria, intraradical hyphae, arbuscules and vesicles were scored. Roots of the har1-1 parental line were heavily colonised by six weeks after inoculation with the AM fungus Glomus intraradices showing the typical Arum-type colonisation pattern. Five mutants lacked internal root colonisation with blocks either at the surface of epidermal cells or at the outer tangential wall of cortical cells. These AM– lines showed some differences in relation to the amount of extraradical hyphae, the number of appressoria, and the degree of abnormal appressorium morphology. Four mutants had internal root colonisation but at a lower level than the parental line. Two mutants showed no difference from the parental line. Results of this study provide additional genetic resources for studying the mechanism of root colonisation by AM fungi.

scholarly journals Systemic induction of phosphatidylinositol-based signaling in leaves of arbuscular mycorrhizal rice plants

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Sonia Campo ◽  
Blanca San Segundo
Keyword(s):  
Molecular Mechanisms ◽  
Arbuscular Mycorrhizal ◽  
Am Fungi ◽  
Gene Families ◽  
Transcriptional Responses ◽  
Inositol Polyphosphates ◽  
Rice Plants ◽  
Am Fungus ◽  
Am Symbiosis ◽  
Hormone Biosynthesis

Abstract Most land plants form beneficial associations with arbuscular mycorrhizal (AM) fungi which improves mineral nutrition, mainly phosphorus, in the host plant in exchange for photosynthetically fixed carbon. Most of our knowledge on the AM symbiosis derives from dicotyledonous species. We show that inoculation with the AM fungus Funneliformis mosseae stimulates growth and increases Pi content in leaves of rice plants (O. sativa, cv Loto, ssp japonica). Although rice is a host for AM fungi, the systemic transcriptional responses to AM inoculation, and molecular mechanisms underlying AM symbiosis in rice remain largely elusive. Transcriptomic analysis identified genes systemically regulated in leaves of mycorrhizal rice plants, including genes with functions associated with the biosynthesis of phospholipids and non-phosphorus lipids (up-regulated and down-regulated, respectively). A coordinated regulation of genes involved in the biosynthesis of phospholipids and inositol polyphosphates, and genes involved in hormone biosynthesis and signaling (jasmonic acid, ethylene) occurs in leaves of mycorrhizal rice. Members of gene families playing a role in phosphate starvation responses and remobilization of Pi were down-regulated in leaves of mycorrhizal rice. These results demonstrated that the AM symbiosis is accompanied by systemic transcriptional responses, which are potentially important to maintain a stable symbiotic relationship in rice plants.

scholarly journals Expression of Maize and Fungal Nitrate Reductase Genes in Arbuscular Mycorrhiza

1998 ◽  
Vol 11 (6) ◽  
pp. 439-448 ◽  
Author(s):  
Michael Kaldorf ◽  
Elmon Schmelzer ◽  
Hermann Bothe
Keyword(s):  
Nitrate Reductase ◽  
Glomus Intraradices ◽  
Mrna Level ◽  
Nitrate Assimilation ◽  
Arbuscular Mycorrhizal ◽  
Am Fungi ◽  
Gene Coding ◽  
Polymerase Chain Reaction Technology ◽  
Am Fungus

The role of arbuscular mycorrhizal (AM) fungi in assisting their host plant in nitrate assimilation was studied. With polymerase chain reaction technology, part of the gene coding for the nitrate reductase (NR) apoprotein from either the AM fungus Glomus intraradices or from maize was specifically amplified and subsequently cloned and sequenced. Northern (RNA) blot analysis with these probes indicated that the mRNA level of the maize gene was lower in roots and shoots of mycorrhizal plants than in noncolonized controls, whereas the fungal gene was transcribed in roots of AM plants. The specific NR activity of leaves was significantly lower in AM-colonized maize than in the controls. Nitrite formation catalyzed by NR was mainly NADPH-dependent in roots of AM-colonized plants but not in those of the controls, which is consistent with the fact that NRs of fungi preferentially utilize NADPH as reductant. The fungal NR mRNA was detected in arbuscules but not in vesicles by in situ RNA hybridization experiments. This appears to be the first demonstration of differential formation of transcripts of a gene coding for the same function in both symbiotic partners.

scholarly journals Response of Symbiotic Endomycorrhizal Fungi to Estrogens and Antiestrogens

1997 ◽  
Vol 10 (4) ◽  
pp. 481-487 ◽  
Author(s):  
Marie-Josée Poulin ◽  
Jacques Simard ◽  
Jean-Guy Catford ◽  
Fernand Librie ◽  
Yves Piché
Keyword(s):  
Mammalian Cells ◽  
Glomus Intraradices ◽  
Arbuscular Mycorrhizal ◽  
Am Fungi ◽  
Hyphal Growth ◽  
Biochanin A ◽  
Estrogenic Effects ◽  
Am Symbiosis ◽  
17Β Estradiol ◽  
Molecular Signals

Plant flavonoids reported previously to act as molecular signals in the arbuscular mycorrhizal (AM) symbiosis are known to bind to estrogen receptors and to exert estrogenic effects on mammalian cells. To further investigate the estrogen-like properties of flavonoids the present study examined whether estrogen and antiestrogens have fla-vonoid-related functions in AM fungi. Bioassays were performed in a monoaxenic system with the AM fungi Giga-spora margarita and Glomus intraradices. The plant flavo-noids quercetin and biochanin A stimulate hyphal growth of G. margarita and G. intraradices, respectively. The stimulatory activity of biochanin A studied at concentrations ranging from 0.01 to 10.0 μM shows an estimated EC50 value of 3.26 μM. The present results show that 17β-estradiol and biochanin A exert similar stimulatory effects in G. intraradices. The agonist effect of biochanin A was efficiently suppressed by the new antiestrogen EM-652, which is also consistent with the possible presence of estrogen-binding sites in AM fungi.

Sign in / Sign up

Export Citation Format

Share Document