scholarly journals The Evolutionary Moulding in plant-microbial symbiosis: matching population diversity of rhizobialnodA and legumeNFR5genes

2018 ◽  
Author(s):  
Anna A. Igolkina ◽  
Georgii A. Bazykin ◽  
Elena P. Chizhevskaya ◽  
Nikolai A. Provorov ◽  
Evgeny E. Andronov
Keyword(s):  
Plant Species ◽  
Rhizobium Leguminosarum ◽  
Balancing Selection ◽  
Gene Tree ◽  
Population Diversity ◽  
Nod Factor ◽  
Gene Libraries ◽  
Genes Encoding ◽  
Soil Pool ◽  
Microbial Symbiosis

AbstractWe propose the Evolutionary Moulding hypothesis that population diversities of partners in nitrogen-fixing rhizobium-legume symbiosis are matched, and tested it in nucleotide polymorphism of symbiotic genes encoding two components of the plant-bacteria signalling system. The first component is the rhizobialnodA acyltransferase involved in the fatty acid tail decoration of Nod factor (rhizobia signalling molecule). The second component is the plantNFR5receptor, putatively required for Nod-factor binding.We collected three wild growing legume species together with soil samples adjacent to the roots (soil pool) from one large 25-year fallow:Vicia sativa, Lathyrus pratensisandTrifolium hybridumnodulated by one of the twoRhizobium leguminosarumbiovars (viciaeandtrifolii). For each plant species we prepared three pools for DNA extraction: the plant pool (30 plant indiv.), the nodule pool (90 nodules) and the soil pool (30 samples).NFR5gene libraries from the plant pool andnodA gene libraries from nodule and soil pools were sequenced by Sanger technology and High-throughput pyrosequencing, respectively. Analysis of the data demonstrated concordance in population diversities of one symbiotic partner (rhizobia) the second partner (legume host), in line with the Evolutionary Moulding hypothesis. This effect was evinced by the following observations for each plant species: (1) significantly increased diversity in the nodulenodA popset (set of gene sequences derived from the nodule population) compared to the soil popset; (2) a monotonic relationship between the diversity in the plantNFR5gene popset and the nodule rhizobialnodA gene popset; and (3) higher topological similarity of theNFR5gene tree with thenodA gene tree of the nodule popset, than with thenodA gene tree of the soil popset. Both nonsynonymous diversity and Tajima’s D were increased in the nodule popsets compared to the soil popsets, consistent with relaxation of negative selection and/or admixture of balancing selection underlying the Evolutionary Moulding effect. We propose that the observed genetic concordance arises from the selection of particular characteristics of the nodulenodA genes by the host plant.

scholarly journals Nod Factor-Induced Expression of Leghemoglobin to Study the Mechanism of NH4NO3 Inhibition on Root Hair Deformation

1997 ◽  
Vol 10 (2) ◽  
pp. 215-220 ◽  
Author(s):  
Renze Heidstra ◽  
Gerd Nilsen ◽  
Francisco Martinez-Abarca ◽  
Ab van Kammen ◽  
Ton Bisseling
Keyword(s):  
Gene Expression ◽  
Root Hair ◽  
Rhizobium Leguminosarum ◽  
Cortical Cell ◽  
Brefeldin A ◽  
Marker Genes ◽  
Nodule Formation ◽  
Cdna Clones ◽  
Nod Factor ◽  
Root Hair Deformation

Nod factors secreted by Rhizobium leguminosarum bv. viciae induce root hair deformation, the formation of nodule primordia, and the expression of early nodulin genes in Vicia sativa (vetch). Root hair deformation is induced within 3 h in a small, susceptible zone (±2 mm) of the root. NH4NO3, known to be a potent blocker of nodule formation, inhibits root hair deformation, initial cortical cell divisions, and infection thread formation. To test whether NH4NO3 affects the formation of a component of the Nod factor perception-transduction system, we studied Nod factor-induced gene expression. The differential display technique was used to search for marker genes, which are induced within 1 to 3 h after Nod factor application. Surprisingly, one of the isolated cDNA clones was identified as a leghemoglobin gene (VsLb1), which is induced in vetch roots within 1 h after Nod factor application. By using the drug brefeldin A, it was then shown that VsLb1 activation does not require root hair deformation. The pVsLb1 clone was used as a marker to show that in vetch plants grown in the presence of NH4NO3 Nod factor perception and transduction leading to gene expression are unaffected.

scholarly journals Conservation of noIR in the Sinorhizobium and Rhizobium Genera of the Rhizobiaceae Family

1998 ◽  
Vol 11 (12) ◽  
pp. 1186-1195 ◽  
Author(s):  
Ernö Kiss ◽  
Peter Mergaert ◽  
Boglàrka Olàh ◽  
Attila Kereszt ◽  
Christian Staehelin ◽  
...  
Keyword(s):  
Dna Binding ◽  
Primary Structure ◽  
Dna Hybridization ◽  
Sinorhizobium Meliloti ◽  
Rhizobium Leguminosarum ◽  
Negative Regulation ◽  
Regulatory Proteins ◽  
Dna Binding Domain ◽  
Nod Factor ◽  
Homologous Sequences

In Sinorhizobium meliloti the NolR repressor displays differential negative regulation of nodulation genes and is required for optimal nodulation. Here, we demonstrate that the NolR function is not unique to S. meliloti but is also present in other species of the Rhizobiaceae family. DNA hybridization indicates the presence of nolR homologous sequences in species belonging to the Rhizobium and Sinorhizobium genera while no hybridization signal was detected in species from the Mesorhizobium, Bradyrhizo-bium, Azorhizobium, and Agrobacterium genera. We isolated the nolR gene from the Rhizobium leguminosarum bv. viciae strain TOM and showed that the TOM nolR gene acts similarly to S. meliloti nolR by repressing the expression of both the nodABCIJ and the nodD genes, resulting in decreased Nod factor production. The presence of a functional nolR gene in R. leguminosarum is correlated with an increased rate and extent of nodulation of pea. The conserved primary structure, the location of the DNA-binding domain, and the similar size of NolR proteins, compared with a family of small bacterial regulatory proteins including HlyU, SmtB, and the ArsR-type regulators, revealed that NolR belongs to this family.

Synthesis of 2E,4E,6E,11Z-octadecatetraenoic acid of the Rhizobium leguminosarum biovar viciae Nod factor

2005 ◽  
Vol 46 (9) ◽  
pp. 1537-1539 ◽  
Author(s):  
Joseph-Nathan Téné Ghomsi ◽  
Olivine Goureau ◽  
Michel Treilhou
Keyword(s):  
Rhizobium Leguminosarum ◽  
Nod Factor ◽  
Octadecatetraenoic Acid

scholarly journals Symbiosis genes show a unique pattern of introgression and selection within a Rhizobium leguminosarum species complex

2020 ◽  
Vol 6 (4) ◽  
Author(s):  
Maria Izabel A. Cavassim ◽  
Sara Moeskjær ◽  
Camous Moslemi ◽  
Bryden Fields ◽  
Asger Bachmann ◽  
...  
Keyword(s):  
Species Complex ◽  
Rhizobium Leguminosarum ◽  
De Novo ◽  
Gene Tree ◽  
Species Boundaries ◽  
Content Type ◽  
Genomic Location ◽  
Tree Traversal ◽  
Four Blocks ◽  
Core Genes

Rhizobia supply legumes with fixed nitrogen using a set of symbiosis genes. These can cross rhizobium species boundaries, but it is unclear how many other genes show similar mobility. Here, we investigate inter-species introgression using de novo assembly of 196 Rhizobium leguminosarum sv. trifolii genomes. The 196 strains constituted a five-species complex, and we calculated introgression scores based on gene-tree traversal to identify 171 genes that frequently cross species boundaries. Rather than relying on the gene order of a single reference strain, we clustered the introgressing genes into four blocks based on population structure-corrected linkage disequilibrium patterns. The two largest blocks comprised 125 genes and included the symbiosis genes, a smaller block contained 43 mainly chromosomal genes, and the last block consisted of three genes with variable genomic location. All introgression events were likely mediated by conjugation, but only the genes in the symbiosis linkage blocks displayed overrepresentation of distinct, high-frequency haplotypes. The three genes in the last block were core genes essential for symbiosis that had, in some cases, been mobilized on symbiosis plasmids. Inter-species introgression is thus not limited to symbiosis genes and plasmids, but other cases are infrequent and show distinct selection signatures.

scholarly journals Virus Synergy in Transgenic Plants

2000 ◽  
Author(s):  
Peter Palukaitis ◽  
Amit Gal-On ◽  
Milton Zaitlin ◽  
Victor Gaba
Keyword(s):  
Transgenic Plants ◽  
Plant Species ◽  
Natural Resistance ◽  
Virus Accumulation ◽  
Synergistic Interactions ◽  
Viral Genes ◽  
Genes Encoding ◽  
Movement Synergy ◽  
Plant Genes ◽  
Viral Sequences

Transgenic plants expressing viral genes offer novel means of engendering resistance to those viruses. However, some viruses interact synergistically with other viruses and it is now known that transgenic plants expressing particular genes of one virus may also mediate synergy with a second virus. Thus, our specific objectives were to (1) determine if transgenic plants resistant to one virus showed synergy with another virus; (2) determine what viral sequences were essential for synergy; and (3) determine whether one of more mechanisms were involved i synergy. This project would also enable an evaluation of the risks of synergism associated with the use of such transgenic plants. The conclusion deriving from this project are as follows: - There is more than one mechanism of synergy. - The CMV 2b gene is required for synergistic interactions. - Synergy between a potyvirus and CMV can break natural resistance limiting CMV movement. - Synergy operates at two levels - increase in virus accumulation and increase in pathology - independently of each other. - Various sequences of CMV can interact with the host to alter pathogenicity and affect virus accumulation. - The effect of synergy on CMV satellite RNA accumulatio varies in different systems. - The HC-Pro gene may only function in host plant species to induce synergy. - The HC-Pro is a host range determinant of potyviruses. - Transgenic plants expressing some viral sequences showed synergy with one or more viruses. Transgenic plants expressing CMV RNA 1, PVY NIb and the TMV 30K gene all showed synergy with at least one unrelated virus. - Transgenic plants expressing some viral sequences showed interference with the infection of unrelated viruses. Transgenic plants expressing the TMV 30K, 54K and 126K genes, the PVY NIb gene, or the CMV 3a gene all showed some level of interference with the accumulation (and in some cases the pathology) of unrelated viruses. From our observations, there are agricultural implications to the above conclusions. It is apparent that before they are released commercially, transgenic plants expressing viral sequences for resistance to one virus need to be evaluated fro two properties: - Synergism to unrelated viruses that infect the same plant. Most of these evaluations can be made in the greenhouse, and many can be predicted from the known literature of viruses known to interact with each other. In other cases, where transgenic plants are being generated from new plant species, the main corresponding viruses from the same known interacting genera (e.g., potexviruses and cucumoviruses, potyviruses and cucumoviruses, tobamoviruses and potexviruses, etc.) should be evaluated. - Inhibition or enhancement of other resistance genes. Although it is unlikely that plants to be released would be transformed with HC-Pro or 2b genes, there may be other viral genes that can affect the expression of plant genes encoding resistance to other pathogens. Therefore, transgenic plants expressing viral genes to engender pathogen-derived resistance should be evaluated against a spectrum of other pathogens, to determine whether those resistance activities are still present, have been lost, or have been enhanced!

scholarly journals Biological activity of Nod factors

2020 ◽  
Author(s):  
Dominika Kidaj ◽  
Mikolaj Krysa ◽  
Katarzyna Susniak ◽  
Joanna Matys ◽  
Iwona Komaniecka ◽  
...  
Keyword(s):  
Molecular Level ◽  
Root Nodules ◽  
Cortical Cell ◽  
Plant Tissues ◽  
Nod Factors ◽  
Nod Factor ◽  
Expression Of Genes ◽  
Root Hair Deformation ◽  
Low Concentrations ◽  
Genes Encoding

Chemically, the Nod factors (NFs) are lipochitooligosaccharides, produced mainly by bacteria of the Rhizobium genus. They are the main signaling molecules involved in the initiation of symbiosis between rhizobia and legume plants. Nod factors affect plant tissues at very low concentrations, even as low as 10–12 mol/L. They induce root hair deformation, cortical cell division, and root nodules’ formation in the host plant. At the molecular level, the cytoskeleton is reorganized and expression of genes encoding proteins called nodulins is induced in response to Nod factors in the cell. Action of Nod factors is highly specific because it depends on the structure of a particular Nod factor involved, as well as the plant receptor reacting with it.

Protein disulphide isomerase family in bread wheat (Triticum aestivum L.): genomic structure, synteny conservation and phylogenetic analysis

2011 ◽  
Vol 9 (2) ◽  
pp. 342-346 ◽  
Author(s):  
E. d'Aloisio ◽  
A. R. Paolacci ◽  
A. P. Dhanapal ◽  
O. A. Tanzarella ◽  
E. Porceddu ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Gene Family ◽  
Bread Wheat ◽  
Plant Species ◽  
Genomic Structure ◽  
Triticum Aestivum L ◽  
Protein Disulphide Isomerase ◽  
Homoeologous Genes ◽  
Genes Encoding ◽  
High Level

Eight genes encoding protein disulphide isomerase (PDI)-like proteins in bread wheat were cloned and characterized and their genomic structure was compared with that of homoeologous genes isolated from other plant species. Fourteen wheat cDNA sequences of PDI-like genes were amplified and cloned; eight of them were relative to distinct PDI-like genes, whereas six corresponded to homoeologous sequences. Also, the genomic sequences of the eight non-homoeologous genes were amplified and cloned. Phylogenetic analysis, which included eight genes encoding PDI-like proteins and the gene encoding the typical PDI, assigned at least one of them to each of the eight major clades identified in the phylogenetic tree of the PDI gene family of plants. The close chromosome synteny between wheat and rice was confirmed by the location of the homoeologous genes of the PDI family in syntenic regions of the two species. Within the same phylogenetic group, a high level of conservation, in terms of sequence homology, genomic structure and domain organization, was detected between wheat and the other plant species. The high level of conservation of sequence and genomic organization within the PDI gene family, even between distant plant species, might be ascribed to the key metabolic roles of their protein products.

Sign in / Sign up

Export Citation Format

Share Document