scholarly journals Differential Expression Patterns of an Acidic Chitinase and a Basic Chitinase in the Root Nodule of Elaeagnus umbellata

2002 ◽  
Vol 15 (3) ◽  
pp. 209-215 ◽  
Author(s):  
Ho Bang Kim ◽  
Chung Sun An

Two cDNA clones encoding chitinase were isolated from a root nodule cDNA library of Elaeagnus umbellata by the hybridization-competition method. The two clones, EuNOD-CHT1 and EuNOD-CHT2, encode for 335 and 317 amino acid residues with the molecular mass of mature proteins being 33.3 and 31.1 kDa, respectively. The two chitinases showed similar protein structures consisting of four domains: hydrophobic signal peptide domain, cysteine-rich chitin-binding domain, hinge domain, and catalytic domain. The EuNOD-CHT1 gene showed similar expression levels in root nodules and leaves, with no detection of transcripts in the roots. The EuNOD-CHT2 gene was expressed at similarly high levels in the roots and root nodules, but at a very low level in the leaves. In situ hybridization showed that EuNOD-CHT1 transcripts were strongly detected in the meristem zone, but weakly detected in the outer cortex layer of the root nodule and in the uninfected cells of the fixation zone. On the other hand, EuNOD-CHT2 transcripts were strongly detected in the infected cells of the fixation zone and central vascular system, but weakly detected in the senescence zone. Our results suggest that the two chitinases may play different biological roles in the root nodule. EuNOD-CHT2 may be involved in a defense response against internal symbionts, external pathogens, or both, while EuNOD-CHT1 may be involved in normal plant development as well as in a defensive role against external pathogens.

2001 ◽  
Vol 28 (9) ◽  
pp. 951
Author(s):  
Sang Ho Lee ◽  
Ho Bang Kim ◽  
Chung Sun An

This paper originates from an address at the 8th International Symposium on Nitrogen Fixation with Non-Legumes, Sydney, NSW, December 2000 Two cDNA clones encoding S-adenosyl-L-methionine synthetase (SAMS) were isolated from the root nodule cDNA library of Elaeagnus umbellata Thunberg and analysed on the basis of deduced amino acid sequence and expression pattern. Two EuSAMS clones shared 75–84% identity at the nucleotide level, and 85–95% identity at the amino acid level, with the other plant SAMS genes. Genomic Southern hybridization revealed the presence of more than two copies of SAMS genes in the genome of E. umbellata. Reverse transcriptase-mediated polymerase chain reaction (RT–PCR) analysis showed EuSAMS1 transcripts were more abundant than those of EuSAMS2. Similar to the expression pattern of other plant SAMS genes, both genes were expressed at higher levels in root than in leaf. During nodule development, expression of both genes was increased, with the highest level at 6–8 week after inoculation, and decreased rapidly thereafter. In situ hybridization analysis also showed both SAMS transcripts in the meristem zone, the infected cells of the fixation zone and in the central vascular system of root nodules. However, EuSAMS2 transcripts were strongly detected in the prefixation zone, whereas EuSAMS1 transcripts were hardly detected. These results suggest different regulatory mechanisms for the two genes in the root nodule. The expression pattern of SAMS genes in the root nodule may correlate mostly with cell wall synthesis, polyamine biosynthesis and other methylation-mediated functions.


1999 ◽  
Vol 77 (9) ◽  
pp. 1270-1278
Author(s):  
Ho Bang Kim ◽  
Chung Sun An

A cDNA clone encoding polyubiquitin was isolated from a root nodule cDNA library of Elaeagnus umbellata Thunb. by differential hybridization, and its molecular aspects were characterized. The polyubiquitin clone pEuNOD-PUB1 has an insert size of 1642 bp and has the capacity to code for a 458 amino acid residue polyubiquitin protein. The derived amino acid sequence indicates that pEuNOD-PUB1 encodes a polyprotein consisting of six repeats of ubiquitin monomer, except for the last repeat, which has two additional amino acids (Asp-Phe) to be removed in the course of polyubiquitin processing into monomer. The molecular mass of ubiquitin monomer, consisting of 76 amino acids, was predicted to be 8524 Da, and the pI value was predicted to be 7.57. The nucleotide sequence of ubiquitin monomers from pEuNOD-PUB1 showed 73.1-86.0% sequence similarity with those from other organisms. The polyubiquitin mRNA content was four to six times higher in the root nodules than in the leaves and roots. In situ hybridization results showed polyubiquitin transcripts were strongly detected in the meristem zone, in infected cells of the fixation zone, and in the central vascular system. Genomic Southern hybridization revealed that polyubiquitin genes are present as a small multigene family in the genome of E. umbellata.Key words: Elaeagnus umbellata, root nodule, cDNA, polyubiquitin, Northern hybridization, in situ hybridization.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Tao Fan ◽  
Yu-Zhen Zhao ◽  
Jing-Fang Yang ◽  
Qin-Lai Liu ◽  
Yuan Tian ◽  
...  

AbstractEukaryotic cells can expand their coding ability by using their splicing machinery, spliceosome, to process precursor mRNA (pre-mRNA) into mature messenger RNA. The mega-macromolecular spliceosome contains multiple subcomplexes, referred to as small nuclear ribonucleoproteins (snRNPs). Among these, U1 snRNP and its central component, U1-70K, are crucial for splice site recognition during early spliceosome assembly. The human U1-70K has been linked to several types of human autoimmune and neurodegenerative diseases. However, its phylogenetic relationship has been seldom reported. To this end, we carried out a systemic analysis of 95 animal U1-70K genes and compare these proteins to their yeast and plant counterparts. Analysis of their gene and protein structures, expression patterns and splicing conservation suggest that animal U1-70Ks are conserved in their molecular function, and may play essential role in cancers and juvenile development. In particular, animal U1-70Ks display unique characteristics of single copy number and a splicing isoform with truncated C-terminal, suggesting the specific role of these U1-70Ks in animal kingdom. In summary, our results provide phylogenetic overview of U1-70K gene family in vertebrates. In silico analyses conducted in this work will act as a reference for future functional studies of this crucial U1 splicing factor in animal kingdom.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yuta Takahashi ◽  
Kaori Shiojiri ◽  
Akira Yamawo

AbstractAboveground communication between plants is well known to change defense traits in leaves, but its effects on belowground plant traits and soil characteristics have not been elucidated. We hypothesized that aboveground plant-to-plant communication reduces root nodule symbiosis via induction of bactericidal chemical defense substances and changes the soil nutrient environment. Soybean plants were exposed to the volatile organic compounds (VOCs) from damaged shoots of Solidago canadensis var. scabra, and leaf defense traits (total phenolics, saponins), root saponins, and root nodule symbiosis traits (number and biomass of root nodules) were measured. Soil C/N ratios and mineral concentrations were also measured to estimate the effects of resource uptake by the plants. We found that total phenolics were not affected. However, plants that received VOCs had higher saponin concentrations in both leaves and roots, and fewer root nodules than untreated plants. Although the concentrations of soil minerals did not differ between treatments, soil C/N ratio was significantly higher in the soil of communicated plants. Thus, the aboveground plant-to-plant communication led to reductions in root nodule symbiosis and soil nutrient concentrations. Our results suggest that there are broader effects of induced chemical defenses in aboveground plant organs upon belowground microbial interactions and soil nutrients, and emphasize that plant response based on plant-to-plant communications are a bridge between above- and below-ground ecosystems.


Plants ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1154
Author(s):  
Hongjia Zhang ◽  
Seong-Gyu Jang ◽  
San Mar Lar ◽  
Ah-Rim Lee ◽  
Fang-Yuan Cao ◽  
...  

Starch is a major ingredient in rice, and the amylose content of starch significantly impacts rice quality. OsSS (starch synthase) is a gene family related to the synthesis of amylose and amylopectin, and 10 members have been reported. In the present study, a synteny analysis of a novel family member belonging to the OsSSIV subfamily that contained a starch synthase catalytic domain showed that three segmental duplications and multiple duplications were identified in rice and other species. Expression data showed that the OsSS gene family is involved in diverse expression patterns. The prediction of miRNA targets suggested that OsSS are possibly widely regulated by miRNA functions, with miR156s targeted to OsSSII-3, especially. Haplotype analysis exhibited the relationship between amylose content and diverse genotypes. These results give new insight and a theoretical basis for the improved amylose content and eating quality of rice.


2003 ◽  
Vol 16 (9) ◽  
pp. 808-816 ◽  
Author(s):  
Carole Santi ◽  
Uritza von Groll ◽  
Ana Ribeiro ◽  
Maurizio Chiurazzi ◽  
Florence Auguy ◽  
...  

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 (GmENOD402). In the actinorhizal Allocasuarina sp., CgENOD40-GUS and GmENOD40-2-GUS showed similar expression patterns in both vegetative and symbiotic development, and neither promoter was active during nodule induction. The nonsymbiotic expression pattern of CgENOD40-GUS in the legume genus Lotus resembled the nonsymbiotic expression patterns of legume ENOD40 genes however, in contrast to GmENOD40-2-GUS, CgENOD40-GUS was not active during nodule induction. The fact that only legume, not actinorhizal, ENOD40 genes are induced during legume nodule induction can be linked to the phloem unloading mechanisms established in the zones of nodule induction in the roots of both types of host plants.


2003 ◽  
Vol 16 (4) ◽  
pp. 281-288 ◽  
Author(s):  
Tomomi Nakagawa ◽  
Tomoko Izumi ◽  
Mari Banba ◽  
Yosuke Umehara ◽  
Hiroshi Kouchi ◽  
...  

Phosphoenolpyruvate carboxylases (PEPCs), one form of which in each legume species plays a central role in the carbon metabolism in symbiotic root nodules, are activated through phosphorylation of a conserved residue by a specific protein kinase (PEPC-PK). We characterized the cDNAs for two PEPC isoforms of Lotus japonicus, an amide-translocating legume that forms determinate nodules. One gene encodes a nodule-enhanced form, which is more closely related to the PEPCs in amide-type indeterminate nodules than those in ureide-type determinate nodules. The other gene is expressed in shoots and roots at a low level. Both forms have the putative phosphorylation site, Ser11. We also isolated a cDNA and the corresponding genomic DNA for PEPC-PK of L. japonicus. The recombinant PEPC-PK protein expressed in Escherichia coli phosphorylated recombinant maize C4-form PEPC efficiently in vitro. The level of mRNA for PEPC-PK was high in root nodules, and those in shoots and roots were also significant. In situ hybridization revealed that the expression patterns of the transcripts for PEPC and PEPC-PK were similar in mature root nodules, but were different in emerging nodules. When L. japonicus seedlings were subjected to prolonged darkness and subsequent illumination, the activity of PEPC-PK and the mRNA levels of both PEPC and PEPC-PK in nodules decreased and then recovered, suggesting that they are regulated according to the amounts of photosynthates transported from shoots.


Plants ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 2169
Author(s):  
Hailian Zhou ◽  
Jiaying Li ◽  
Xueyuan Liu ◽  
Xiaoshuang Wei ◽  
Ziwei He ◽  
...  

Bcl-2-associated athanogene (BAG), a group of proteins evolutionarily conserved and functioned as co-chaperones in plants and animals, is involved in various cell activities and diverse physiological processes. However, the biological functions of this gene family in rice are largely unknown. In this study, we identified a total of six BAG members in rice. These genes were classified into two groups, OsBAG1, -2, -3, and -4 are in group I with a conserved ubiquitin-like structure and OsBAG5 and -6 are in group Ⅱ with a calmodulin-binding domain, in addition to a common BAG domain. The BAG genes exhibited diverse expression patterns, with OsBAG4 showing the highest expression level, followed by OsBAG1 and OsBAG3, and OsBAG6 preferentially expressed in the panicle, endosperm, and calli. The co-expression analysis and the hierarchical cluster analysis indicated that the OsBAG1 and OsBAG3 were co-expressed with primary cell wall-biosynthesizing genes, OsBAG4 was co-expressed with phytohormone and transcriptional factors, and OsBAG6 was co-expressed with disease and shock-associated genes. β-glucuronidase (GUS) staining further indicated that OsBAG3 is mainly involved in primary young tissues under both primary and secondary growth. In addition, the expression of the BAG genes under brown planthopper (BPH) feeding, N, P, and K deficiency, heat, drought and plant hormones treatments was investigated. Our results clearly showed that OsBAGs are multifunctional molecules as inferred by their protein structures, subcellular localizations, and expression profiles. BAGs in group I are mainly involved in plant development, whereas BAGs in group II are reactive in gene regulations and stress responses. Our results provide a solid basis for the further elucidation of the biological functions of plant BAG genes.


Author(s):  
Josep Ramoneda ◽  
Johannes Le Roux ◽  
Stefanie Stadelmann ◽  
Emmanuel Frossard ◽  
Beat Frey ◽  
...  

AbstractSoil microbial community coalescence, whereby entire microbial communities mix and compete in a new environmental setting, is a widespread phenomenon whose applicability for targeted root microbiome assembly has not been studied. Using a legume shrub adapted to nutrient poor soil, we tested for the first time how the assembly of communities of rhizobial root nodule symbionts is affected by the interaction of coalescence and fertilization. Seedlings of the rooibos [Aspalathus linearis (Burm.f.) Dahlg.], were raised in pairwise mixtures of soil from cultivated and uncultivated land of five farms, as well as the individual mixture components. A fragment of the symbiosis maker gene, nodA, was sequenced to characterize the taxonomic turnover of the rhizobia associated with all root nodules at the age of eight month. Soil mixing promoted taxonomic turnover in the rhizobial communities, while fertilization amplified such turnover by increasing the number of rhizobia that became more abundant after soil mixing. Soil mixing and fertilization had a synergistic effect on the abundance of a particular taxon, which was rare in the component soils but became highly abundant in fertilized plants raised in soil mixtures. These findings provide the first evidence that fertilizer addition can interact with soil microbial community coalescence, probably through increasing the chances for rare strains to prioritize root nodule colonization. The combination of soil mixing and fertilizer addition may be a still unexplored measure to (re)introduce root microbial mutualists in arable land.


2021 ◽  
Author(s):  
Fu Quan Yao ◽  
Xiao Hui Li ◽  
He Wang ◽  
Yu Ning Song ◽  
Zhong Qing Li ◽  
...  

Abstract Background: Tiller number is a factor determining panicle number and grain yield in wheat (Triticum aestivum L.). Auxin plays an important role in the regulation of branch production. PIN-FORMED 1 (PIN1), an auxin efflux carrier, plays a role in the regulation of tiller number in rice (Oryza sativa); however, little is known on the roles of PIN1 in wheat. Results: Nine homologs of TaPIN1 genes were identified in wheat, of which TaPIN1-6 genes showed higher expression in the stem apex and young leaf in wheat, and the TaPIN1-6a protein was localized in the plasma membrane. The down-expression of TaPIN1s increased the tiller number in TaPIN1-RNA interference (TaPIN1-RNAi) transgenic wheat plants, indicating that auxin might mediate the axillary bud production. By contrast, the spikelet number, grain number per panicle, and the 1000-grain weight were decreased in the TaPIN1-RNAi transgenic wheat plants compared with those in the wild type. Conclusions: Phylogenetic analysis and expression patterns of nine TaPIN1 genes, and their protein structures and subcellular localization of TaPIN1-6a protein were analyzed. Down-regulated expression of TaPIN1 genes increased the tiller numbers of transgenic wheat lines. Our study suggests that TaPIN1s is required for the regulation of grain yield in wheat.


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