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1.
Chinese Journal of Biotechnology ; (12): 122-136, 2024.
Article in Chinese | WPRIM | ID: wpr-1008084

ABSTRACT

Excavating the quantitative trait locus (QTL) associated with rice cooking quality, analyzing candidate genes, and improving cooking quality-associated traits of rice varieties by genetic breeding can effectively improve the taste of rice. In this study, we used the indica rice HZ, the japonica rice Nekken2 and 120 recombinant inbred lines (RILs) populations constructed from them as experimental materials to measure the gelatinization temperature (GT), gel consistency (GC) and amylose content (AC) of rice at the maturity stage. We combined the high-density genetic map for QTL mapping. A total of 26 QTLs associated with rice cooking quality (1 QTL associated with GT, 13 QTLs associated with GC, and 12 QTLs associated with AC) were detected, among which the highest likelihood of odd (LOD) value reached 30.24. The expression levels of candidate genes in the localization interval were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR), and it was found that the expression levels of six genes were significantly different from that in parents. It was speculated that the high expression of LOC_Os04g20270 and LOC_Os11g40100 may greatly increase the GC of rice, while the high expression of LOC_Os01g04920 and LOC_Os02g17500 and the low expression of LOC_Os03g02650 and LOC_Os05g25840 may reduce the AC. The results lay a molecular foundation for the cultivation of new high-quality rice varieties, and provide important genetic resources for revealing the molecular regulation mechanism of rice cooking quality.


Subject(s)
Quantitative Trait Loci , Oryza/genetics , Plant Breeding , Cooking , Genetic Association Studies
2.
Chinese Journal of Biotechnology ; (12): 713-723, 2023.
Article in Chinese | WPRIM | ID: wpr-970402

ABSTRACT

Iron (Fe) deficiency and excess cadmium (Cd) in rice grain are important problems to be solved in agricultural production. Previous studies have shown that OsVIT1 and OsVIT2 are vacuolar iron transporters. In this study, wild-type ZH11 was selected as the background material and OsVIT1 and OsVIT2 were overexpressed in endosperm by using endosperm specific promoter Glb-1. Field experiments were conducted to study the effect of OsVIT1 and OsVIT2 overexpression on Fe and Cd accumulation in different parts of rice. The results showed that OsVIT1 overexpression in endosperm significantly reduced Fe content in grain by about 50%, while significantly increased zinc (Zn) and copper (Cu) contents in straw and Cu content in grain. OsVIT2 overexpression in endosperm significantly decreased Fe and Cd contents in grain by about 50%, and significantly increased Fe content in straw by 45%-120%. Overexpression of OsVIT1 and OsVIT2 in endosperm did not affect the agronomic traits of rice. In conclusion, OsVIT1 and OsVIT2 overexpression in endosperm reduced Fe accumulation in rice grain, which did not achieve the expected effect. OsVIT2 overexpression in endosperm also decreased Cd accumulation in grain and increased Fe accumulation in straw, which provided reference for iron biofortification and cadmium reduction in rice.


Subject(s)
Cadmium , Endosperm/chemistry , Oryza/genetics , Iron , Zinc , Edible Grain , Soil Pollutants
3.
Braz. j. biol ; 82: 1-24, 2022.
Article in English | LILACS, VETINDEX | ID: biblio-1468567

ABSTRACT

The mutations are genetic changes in the genome sequences and have a significant role in biotechnology, genetics, and molecular biology even to find out the genome sequences of a cell DNA along with the viral RNA sequencing. The mutations are the alterations in DNA that may be natural or spontaneous and induced due to biochemical reactions or radiations which damage cell DNA. There is another cause of mutations which is known as transposons or jumping genes which can change their position in the genome during meiosis or DNA replication. The transposable elements can induce by self in the genome due to cellular and molecular mechanisms including hypermutation which caused the localization of transposable elements to move within the genome. The use of induced mutations for studying the mutagenesis in crop plants is very common as well as a promising method for screening crop plants with new and enhanced traits for the improvement of yield and production. The utilization of insertional mutations through transposons or jumping genes usually generates stable mutant alleles which are mostly tagged for the presence or absence of jumping genes or transposable elements. The transposable elements may be used for the identification of mutated genes in crop plants and even for the stable insertion of transposable elements in mutated crop plants. The guanine nucleotide-binding (GTP) proteins have an important role in inducing tolerance in rice plants to combat abiotic stress conditions.


Mutações são alterações genéticas nas sequências do genoma e têm papel significativo na biotecnologia, genética e biologia molecular, até mesmo para descobrir as sequências do genoma de um DNA celular junto com o sequenciamento do RNA viral. As mutações são alterações no DNA que podem ser naturais ou espontâneas e induzidas devido a reações bioquímicas ou radiações que danificam o DNA celular. Há outra causa de mutações, conhecida como transposons ou genes saltadores, que podem mudar sua posição no genoma durante a meiose ou a replicação do DNA. Os elementos transponíveis podem induzir por si próprios no genoma devido a mecanismos celulares e moleculares, incluindo hipermutação que causou a localização dos elementos transponíveis para se moverem dentro do genoma. O uso de mutações induzidas para estudar a mutagênese em plantas cultivadas é muito comum, bem como um método promissor para a triagem de plantas cultivadas com características novas e aprimoradas para a melhoria da produtividade e da produção. A utilização de mutações de inserção por meio de transposons ou genes saltadores geralmente gera alelos mutantes estáveis que são marcados quanto à presença ou ausência de genes saltadores ou elementos transponíveis. Os elementos transponíveis podem ser usados para a identificação de genes mutados em plantas de cultivo e até mesmo para a inserção estável de elementos transponíveis em plantas de cultivo mutadas. As proteínas de ligação ao nucleotídeo guanina (GTP) têm papel importante na indução de tolerância em plantas de arroz para combater as condições de estresse abiótico.


Subject(s)
DNA Transposable Elements/genetics , Mutation/genetics , Guanine Nucleotides/analysis , Oryza/genetics
4.
Braz. j. biol ; 82: e250700, 2022.
Article in English | LILACS, VETINDEX | ID: biblio-1278476

ABSTRACT

The mutations are genetic changes in the genome sequences and have a significant role in biotechnology, genetics, and molecular biology even to find out the genome sequences of a cell DNA along with the viral RNA sequencing. The mutations are the alterations in DNA that may be natural or spontaneous and induced due to biochemical reactions or radiations which damage cell DNA. There is another cause of mutations which is known as transposons or jumping genes which can change their position in the genome during meiosis or DNA replication. The transposable elements can induce by self in the genome due to cellular and molecular mechanisms including hypermutation which caused the localization of transposable elements to move within the genome. The use of induced mutations for studying the mutagenesis in crop plants is very common as well as a promising method for screening crop plants with new and enhanced traits for the improvement of yield and production. The utilization of insertional mutations through transposons or jumping genes usually generates stable mutant alleles which are mostly tagged for the presence or absence of jumping genes or transposable elements. The transposable elements may be used for the identification of mutated genes in crop plants and even for the stable insertion of transposable elements in mutated crop plants. The guanine nucleotide-binding (GTP) proteins have an important role in inducing tolerance in rice plants to combat abiotic stress conditions.


Mutações são alterações genéticas nas sequências do genoma e têm papel significativo na biotecnologia, genética e biologia molecular, até mesmo para descobrir as sequências do genoma de um DNA celular junto com o sequenciamento do RNA viral. As mutações são alterações no DNA que podem ser naturais ou espontâneas e induzidas devido a reações bioquímicas ou radiações que danificam o DNA celular. Há outra causa de mutações, conhecida como transposons ou genes saltadores, que podem mudar sua posição no genoma durante a meiose ou a replicação do DNA. Os elementos transponíveis podem induzir por si próprios no genoma devido a mecanismos celulares e moleculares, incluindo hipermutação que causou a localização dos elementos transponíveis para se moverem dentro do genoma. O uso de mutações induzidas para estudar a mutagênese em plantas cultivadas é muito comum, bem como um método promissor para a triagem de plantas cultivadas com características novas e aprimoradas para a melhoria da produtividade e da produção. A utilização de mutações de inserção por meio de transposons ou genes saltadores geralmente gera alelos mutantes estáveis que são marcados quanto à presença ou ausência de genes saltadores ou elementos transponíveis. Os elementos transponíveis podem ser usados para a identificação de genes mutados em plantas de cultivo e até mesmo para a inserção estável de elementos transponíveis em plantas de cultivo mutadas. As proteínas de ligação ao nucleotídeo guanina (GTP) têm papel importante na indução de tolerância em plantas de arroz para combater as condições de estresse abiótico.


Subject(s)
Oryza/genetics , Phenotype , DNA Transposable Elements/genetics , Gene Expression , Guanosine Triphosphate
5.
Chinese Journal of Biotechnology ; (12): 1981-1993, 2022.
Article in Chinese | WPRIM | ID: wpr-927832

ABSTRACT

The aim of this study was to develop a semi-quantitative immunochromatographic method for rapid detection of Newcastle disease virus (NDV) antibodies by expressing HN protein in rice endosperm bioreactor. The recombinant plasmid pUC57-HN was digested by MlyⅠ and XhoⅠ to retrieve the HN gene, while the intermediate vector pMP3 containing promoter, signal peptide and terminator was digested by NaeⅠ and XhoⅠ. The HN gene and the linearized pMP3 were purified and ligated to form a recombinant plasmid pMP3-HN1. Subsequently, pMP3-HN1 and plant vector pCAMBIA1300 were digested by EcoRⅠ and Hind Ⅲ, and the HN1 gene was cloned into pCAMBIA1300. The recombinant plasmid pCAMBIA1300-HN1 was introduced into Agrobacterium tumefaciens EHA105 by electrotransformation, and the pCAMBIA1300-HN1 was transferred into rice callus by agrobacterium-mediated method. After dark culture, callus screening, differentiation, rooting and transplanting, transgenic rice seeds were obtained 4 months later. PCR identified that the HN gene has been inserted into the rice genome. SDS-PAGE and Western blotting indicated that the HN protein was successfully expressed in the positive rice endosperm. The purity of the HN protein was more than 90% by SP cation exchange chromatography and gel filtration chromatography. According to the national standards for the diagnostic techniques of Newcastle disease HI test (HI≥4log2, positive antibody reaction), a colloidal gold labeled purified HN protein was used to prepare a semi-quantitative test strip by double-antibody sandwich method for rapid detection of NDV antibody. The results showed that the test strip did not cross-react with positive sera against other viruses, and the sensitivity of the test strip reached 1:102 400 for standard positive sera of Newcastle disease. Testing of a total of 308 clinical sera showed that the compliance rate of the test strip with HI test was 97.08%, and the Kappa value was 0.942. In conclusion, high purity recombinant HN protein was obtained from rice endosperm, and a simple, rapid, highly sensitive and highly specific semi-quantitative immunochromatographic strip was developed. The test strip could be used for immune evaluation of the Newcastle disease vaccine.


Subject(s)
Animals , Antibodies, Viral , Chickens , HN Protein/metabolism , Newcastle Disease/prevention & control , Newcastle disease virus/metabolism , Oryza/genetics
6.
Chinese Journal of Biotechnology ; (12): 252-263, 2022.
Article in Chinese | WPRIM | ID: wpr-927709

ABSTRACT

Cultivating salt-alkali tolerant rice varieties is one of the important ways to meet the increasing food demand of growing global population. In this study, twenty-one rice germplasms with different salt-alkali tolerance were treated with six salt-alkali concentrations at germination and seedling stages. The germination potential, germination rate, shoot length, root length, root number, fresh weight of shoot and seedlings were measured. The average value of salt damage rate was used to evaluate the salt-alkali tolerance. As the salt-alkali concentration increases, the inhibition on seed germination and growth became more obvious. Upon treatment with 1% NaCl plus 0.25% NaHCO3, the salt damage rate of germination rate has the largest variation, ranging from 0% to 89.80%. The salt damage rate of each trait shows a similar trend at all concentrations. Four germplasm resources with strong salt-alkali tolerance (Dajiugu, Nippobare, Mowanggu and 02428) and 7 sensitive germplasms were screened. The salt-tolerant gene sequence of 4 salt-alkali tolerant varieties and 3 sensitive germplasms were analyzed. OSHAL3 and OsRR22 were identical among the 7 germplasms, but SKC1 and DST showed clear variations between the salt-alkali tolerant and sensitive germplasms. Besides the salt-alkali tolerant germplasm resources, this study can also serve as a reference for mining of genes involved in salt-alkali tolerance and breeding of salt-alkali tolerant rice varieties.


Subject(s)
Alkalies , Germination , Oryza/genetics , Plant Breeding , Seedlings/genetics
7.
Electron. j. biotechnol ; 54: 47-59, nov.2021. graf, ilus, tab
Article in English | LILACS | ID: biblio-1511064

ABSTRACT

BACKGROUND Profilin proteins (PRFs) are small (12­15 kD) actin-binding protein, which play a significant role in cytoskeleton dynamics and plant development via regulating actin polymerization. Profilins have been well documented in Arabidopsis, Zea mays L. as well as Phaseolus vulgaris, however no such fully characterization of rice (Oryza sativa L.) profilin gene family has been reported thus far. RESULTS In the present study, a comprehensive genome-wide analysis of rice PRF genes was completed and three members were identified. OsPRF1 and OsPRF2 shared 98.5% similarity (6 nucleotide divergence), but the deduced amino acid sequences of OsPRF1 and OsPRF2 are fully identical. In contrast, the OsPRF3 presents relatively lower similarity with OsPRF1 and OsPRF2. Phylogenetic analysis also support that OsPRF1 has a closer relationship with OsPRF2. Expression pattern analysis revealed the differential expression of OsPRFs in tissues of mature plant, which suggested the potential spatial functional specificity for rice profilin genes. Subcellular localization analysis revealed the OsPRFs were localized in cytoplasm and nucleus and all of them could bind actin monomers. Furthermore, abiotic stresses and hormones treatments assay indicated that the three OsPRF genes could be differentially regulated, suggesting that OsPRF genes might participate in different stress processes in rice. CONCLUSIONS Taken together, our study provides a comprehensive analysis of the OsPRF gene family and will provide a basis for further studies on their roles in rice development and in response to abiotic stresses


Subject(s)
Plant Proteins/genetics , Oryza/genetics , Genome, Plant , Profilins/genetics
8.
Biol. Res ; 54: 6-6, 2021. ilus, graf, tab
Article in English | LILACS | ID: biblio-1505798

ABSTRACT

BACKGROUND: Mitochondria play a significant role in plant cytoplasmic male sterility (CMS). In our previous study, mitochondrial complex I genes, nad4, nad5, and nad7 showed polymorphisms between the transgenic CMS line M2BS and its wild type M2B. The sterility mechanism of the M2BS at cytological, physiological, biochemical, and molecular level is not clear. RESULTS: Cytological observation showed that the anthers were light yellow, fissured, invalid in KI-I2, and full of irregularly typical abortion pollen grains in M2BS. Transmission electron microscopic (TEM) observation revealed no nucleus and degraded mitochondria with obscure cristae in anther cells of M2BS. The results of staining for H2O2 presented a large number of electron dense precipitates (edp) in intercellular space of anther cells of M2BS at anthesis. Moreover, the anther respiration rate and complex I activity of M2BS were significantly lower than those of wild type M2B during pollen development. Furthermore, RNA editing results showed only nad7 presented partially edited at 534th nucleotides. The expression of nad5 and nad7 revealed significant differences between M2B and M2BS. CONCLUSIONS: Our data demonstrated that mitochondrial structural degradation and complex I deficiency might be associated with transgenic CMS of rice.


Subject(s)
Oryza/genetics , Electron Transport Complex I/genetics , Plant Infertility , Mitochondria/pathology , Plants, Genetically Modified , Gene Expression Regulation, Plant , Hydrogen Peroxide , Mitochondria/ultrastructure
9.
Electron. j. biotechnol ; 46: 1-7, jul. 2020. ilus, graf, tab
Article in English | LILACS | ID: biblio-1223252

ABSTRACT

BACKGROUND: Fragrance is one of the most important quality traits in rice, and the phenotype is attributed to the loss-of-function betaine aldehyde dehydrogenase (BADH2) gene. At least 12 allelic variations of BADH2 have been identified, and some of these have been applied to rice fragrance breeding using traditional molecular markers and Sanger sequencing techniques. However, these traditional methods have several limitations, such as being very expensive, imprecise, inefficient, and having security issues. Thus, a new molecular marker technology must be developed to improve rice fragrance breeding. RESULTS: In this study, more than 95% of the cultivated fragrant rice varieties belonged to a 7-bp deletion in exon 2 (badh2-E2) or an 8-bp deletion and 3-bp variation in exon 7 (badh2-E7). Both allelic variations resulted in the loss of function of the badh2 gene. We developed two novel SNP molecular markers, SNP_badh2-E2 and SNP_badh2- E7, related to the alleles. Their genotype and phenotype were highly cosegregated in the natural variation of rice accessions, with 160 of the 164 fragrant rice varieties detected with the two markers. These markers cosegregated with the fragrance phenotype in the F2 population. CONCLUSIONS: Two functional SNP molecular markers of badh2-E2 and badh2-E7 allelic variations were developed. These functional SNP molecular markers can be used for genotype and genetic improvement of rice fragrance through marker-assisted selection and will significantly improve the efficiency of fragrant rice breeding and promote commercial molecular breeding of rice in the future.


Subject(s)
Oryza/enzymology , Oryza/genetics , Betaine-Aldehyde Dehydrogenase/metabolism , Genetic Markers , Alleles , Genotyping Techniques/methods , Genotype , Odorants
10.
Braz. arch. biol. technol ; 63: e20180513, 2020. graf
Article in English | LILACS | ID: biblio-1132208

ABSTRACT

Abstract Silicon accumulation is known to improve tolerance of plants under both biotic and abiotic stress. Salinity stress is an inevitable crisis causing wide spread damage to rice leading to food insecurity. The influence of Si (1mM) on two rice cultivars cv. Ghanteswari (high accumulator) and cv.Badami (low accumulator) which differs in Si uptake potential under saline (10ds/m EC) and non- saline conditions were studied in nutrient culture. The Si transporter genes were isolated and characterized to determine their function in salinity tolerance. Under stress, there was an increase in Si accumulation, Na+/K+ ratio, electrolyte leakage, lipid peroxidation and antioxidant activities. On addition of silicon, the K+ uptake increased, membrane damage reduced and osmolytes balance improve under salinity. But, the level of resurgence was varied in both cultivars, due to their differential Si-accumulation. Molecular characterizations of Lsi1 protein revealed its involvement in the movement of ion and water and therefore prevent osmotic stress. The Lsi2 is responsible for removal of Na+, reducing salt toxicity. Silicon accumulation is responsible for maintenance of cell water status, osmotic balance and Na+ ion exclusion during high salinity. The variable relative expression of Lsi2 provides a possible explanation for differential genotypic uptake of silicon.


Subject(s)
Membrane Transport Proteins/genetics , Oryza/genetics , Silicon/metabolism , Gene Expression Regulation , Salinity , Salt Stress , Genotype
11.
An. acad. bras. ciênc ; 90(1): 343-356, Mar. 2018. tab, graf
Article in English | LILACS | ID: biblio-886893

ABSTRACT

ABSTRACT An experiment was conducted to examine the influencing characters on rice by using 64 rice genotypes, including four local landraces, four released cultivars and 56 mutant lines (M5) derived from these genotypes, with application of the genotype by trait (GT) biplot methodology. The first two principal components (PC1 and PC2) accounted for 46.6% of total variation in 64 genotypes. The polygon view of GT biplot suggested seven sections for 64 genotypes. The vertex G38 had good amounts of grain yield, panicle length, hundred grain weight, internodes length, plant height and fertility percentage. Generally based on vector view it was demonstrated that the selection of high grain yield would be performed via thousand grain weight, panicle weight and number of filled grain per panicle. These traits should be considered simultaneously as effective selection criteria evolving high yielding rice genotypes because of their large contribution to grain yield. The genotypes G2, G4 and G7 could be considered for the developing of desirable progenies in the selection strategy of rice improvement programs. This study revealed GT biplot can graphically display the interrelationships among traits. In conclusion, it is recommended the use of GGE biplot to identify superior genotypes for simultaneous improvement of several traits.


Subject(s)
Oryza/genetics , Crops, Agricultural/genetics , Quantitative Trait, Heritable , Oryza/growth & development , Genetic Variation/genetics , Crops, Agricultural/growth & development , Gene-Environment Interaction , Iran
12.
Biol. Res ; 51: 7, 2018. tab, graf
Article in English | LILACS | ID: biblio-888432

ABSTRACT

Abstract Background: Low phosphorus availability is a major factor restricting rice growth. Dongxiang wild rice (Oryza rufipogon Griff.) has many useful genes lacking in cultivated rice, including stress resistance to phosphorus deficiency, cold, salt and drought, which is considered to be a precious germplasm resource for rice breeding. However, the molecular mechanism of regulation of phosphorus deficiency tolerance is not clear. Results: In this study, cDNA libraries were constructed from the leaf and root tissues of phosphorus stressed and untreated Dongxiang wild rice seedlings, and transcriptome sequencing was performed with the goal of elucidating the molecular mechanisms involved in phosphorus stress response. The results indicated that 1184 transcripts were differentially expressed in the leaves (323 up-regulated and 861 down-regulated) and 986 transcripts were differentially expressed in the roots (756 up-regulated and 230 down-regulated). 43 genes were up-regulated both in leaves and roots, 38 genes were up-regulated in roots but down-regulated in leaves, and only 2 genes were down-regulated in roots but up-regulated in leaves. Among these differentially expressed genes, the detection of many transcription factors and functional genes demonstrated that multiple regulatory pathways were involved in phosphorus deficiency tolerance. Meanwhile, the differentially expressed genes were also annotated with gene ontology terms and key pathways via functional classification and Kyoto Encyclopedia of Gene and Genomes pathway mapping, respectively. A set of the most important candidate genes was then identified by combining the differentially expressed genes found in the present study with previously identified phosphorus deficiency tolerance quantitative trait loci. Conclusion: The present work provides abundant genomic information for functional dissection of the phosphorus deficiency resistance of Dongxiang wild rice, which will be help to understand the biological regulatory mechanisms of phosphorus deficiency tolerance in Dongxiang wild rice.


Subject(s)
Phosphorus/deficiency , Oryza/genetics , Stress, Physiological/genetics , Gene Expression Profiling , Seedlings/genetics , Phosphorus/pharmacology , Oryza/drug effects , Oryza/physiology , Stress, Physiological/drug effects , Down-Regulation , Gene Expression Regulation, Plant , Seedlings/drug effects , Seedlings/physiology
13.
Electron. j. biotechnol ; 30: 48-57, nov. 2017. ilus, tab, graf
Article in English | LILACS | ID: biblio-1021453

ABSTRACT

Background: Availability of related rice species is critical for rice breeding and improvement. Two distinct species of domesticated rice exist in the genus Oryza: Oryza sativa (Asian rice) and Oryza glaberrima (African rice). New rice for Africa (NERICA) is derived from interspecific crosses between these two species. Molecular profiling of these germplasms is important for both genetics and breeding studies. We used 30 polymorphic SSR markers to assess the genetic diversity and molecular fingerprints of 53 rice genotypes of O. sativa, O. glaberrima, and NERICA. Results: In total, 180 alleles were detected. Average polymorphism information content and Shannon's information index were 0.638 and 1.390, respectively. Population structure and neighbor-joining phylogenetic tree revealed that 53 genotypes grouped into three distinct subpopulations conforming to the original three groups, except three varieties (IR66417, WAB450-4, MZCD74), and that NERICA showed a smaller genetic distance from O. sativa genotypes (0.774) than from O. glaberrima genotypes (0.889). A molecular fingerprint map of the 53 accessions was constructed with a novel encoding method based on the SSR polymorphic alleles. Ten specific SSR markers displayed different allelic profiles between the O. glaberrima and O. sativa genotypes. Conclusions: Genetic diversity studies revealed that 50 rice types were clustered into different subpopulations whereas three genotypes were admixtures. Molecular fingerprinting and 10 specific markers were obtained to identify the 53 rice genotypes. These results can facilitate the potential utilization of sibling species in rice breeding and molecular classification of O. sativa and O. glaberrima germplasms.


Subject(s)
Oryza/genetics , Genetic Variation , Polymorphism, Genetic , Breeding , DNA Fingerprinting , Microsatellite Repeats , Genotype
14.
Braz. j. microbiol ; 48(3): 537-543, July-Sept. 2017. graf
Article in English | LILACS | ID: biblio-889126

ABSTRACT

Abstract Metallothioneins are a superfamily of low-molecular-weight, cysteine (Cys)-rich proteins that are believed to play important roles in protection against metal toxicity and oxidative stress. The main purpose of this study was to investigate the effect of heterologous expression of a rice metallothionein isoform (OsMTI-1b) on the tolerance of Saccharomyces cerevisiae to Cd2+, H2O2 and ethanol stress. The gene encoding OsMTI-1b was cloned into p426GPD as a yeast expression vector. The new construct was transformed to competent cells of S. cerevisiae. After verification of heterologous expression of OsMTI-1b, the new strain and control were grown under stress conditions. In comparison to control strain, the transformed S. cerevisiae cells expressing OsMTI-1b showed more tolerance to Cd2+ and accumulated more Cd2+ ions when they were grown in the medium containing CdCl2. In addition, the heterologous expression of GST-OsMTI-1b conferred H2O2 and ethanol tolerance to S. cerevisiae cells. The results indicate that heterologous expression of plant MT isoforms can enhance the tolerance of S. cerevisiae to multiple stresses.


Subject(s)
Plant Proteins/genetics , Oryza/genetics , Saccharomyces cerevisiae/metabolism , Cadmium/metabolism , Gene Expression , Ethanol/metabolism , Hydrogen Peroxide/metabolism , Metallothionein/genetics , Plant Proteins/metabolism , Saccharomyces cerevisiae/genetics , Oxidative Stress , Protein Isoforms/genetics , Protein Isoforms/metabolism , Metallothionein/metabolism
15.
An. acad. bras. ciênc ; 89(2): 1251-1258, Apr.-June 2017. tab, graf
Article in English | LILACS | ID: biblio-886681

ABSTRACT

ABSTRACT Tricyclazole is currently one of the fungicides recommended for the treatment of diseases in irrigated rice. However, there is relatively little information on its cytotoxic and genotoxic potential. The objective of this study was to evaluate the cytotoxicity and genotoxicity of rice crop water after apllication of the tricyclazole fungicide through the Allium cepa L. test. The rice crop water samplings were collected before and 1, 15 and 30 days after application of the fungicide in rice plant shoots. The Allium cepa roots were placed in contact with the rice crop water to check for possible chromosomal abnormalities and mitotic index of the bioindicators meristematic cells. The data obtained by the Allium cepa test indicates that the application of the tricyclazole fungicide leads to an increase in the genotoxic activity in the rice crop water, through the appearance of chromosomal abnormalities, without, however, causing significant effects on the mitotic index. The major chromosomal alterations observed were anaphasic and telophasic bridges and laggard chromosomes.


Subject(s)
Oryza/drug effects , Onions/drug effects , Fungicides, Industrial , Oryza/genetics , Water Pollutants, Chemical/toxicity , DNA Damage , Chromosome Aberrations/chemically induced , Crops, Agricultural , Crops, Agricultural/genetics , Agricultural Irrigation , Mitosis/drug effects , Mitotic Index , Mutagenicity Tests/methods
16.
Indian J Biochem Biophys ; 2015 Apr; 52 (2): 161-168
Article in English | IMSEAR | ID: sea-158214

ABSTRACT

Recombinases are known to play an important role in the homology search and strand exchange during meiosis as well as homologous recombination (HR)-mediated DNA repair specifically require Mg2+ ion for their activity. The Ca2+ has been shown to stimulate the strand exchange activity of hDmc1 and ScDmc1 by forming the extended filaments on DNA. Oryza sativa disrupted meiotic cDNA1A (OsDmc1A), a homologue of yeast and human Dmc1 from rice shows the hallmark functions of recombinase. Here, we report the effects of Ca2+ and Mg2+ on OsDmc1A activity from rice (Oryza sativa). OsDmc1A showed a concentration-dependent binding with both single-stranded DNA (ssDNA) and double-stranded DNA (dsDNA) substrates in presence of Mg2+ or Ca2+. The ssDNA and dsDNA binding activities, as well as renaturation activity of OsDmc1A were similar in the presence of Ca2+ or Mg2+. Increasing the Ca2+ or Mg2+ increased the DNA binding, renaturation and strand exchange of OsDmc1A. But, OsDmc1A showed only a slight stimulation of strand exchange activity in presence of Ca2+, when compared the activity in presence of Mg2+. Electron microscopy showed that OsDmc1A formed ring-like structures in presence of Mg2+ or Ca2+. However, OsDmc1A formed filament like structures with both ss and dsDNA in presence of Mg2+ or Ca2+. Taken together, Ca2+ did not affect OsDmc1A recombinase activity significantly.


Subject(s)
Calcium/metabolism , Fluorescence Resonance Energy Transfer/methods , Magnesium/metabolism , Meiosis , Oryza/genetics , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Recombinases/genetics , Recombinases/metabolism
17.
Indian J Biochem Biophys ; 2015 Feb; 52 (1): 86-94
Article in English | IMSEAR | ID: sea-157959

ABSTRACT

DNA polymerase λ (DNA pol λ) is the only reported X-family DNA polymerases in plants and has been shown to play a significant role in dry quiescent seeds, growth, development and nuclear DNA repair. cDNA for DNA pol λ has been reported in Arabidopsis and japonica rice cultivar and has been characterized from E. coli expressed protein, but very little is known about its activity at protein level in plants. The enzymatic activity of DNA pol λ was studied in dry, imbibed and during different germination stages of indica rice IR-8 (salt sensitive) by in-gel activity assay to determine its physiological role in important stages of growth and development. The upstream sequence was also analyzed using plantCARE database and was found to contain several cis-acting elements, including light responsive elements, dehydration responsive elements, Myb binding sites, etc. Hence, 4-day-old germinating seedlings of IR29, a salt-sensitive, but high yielding indica rice cultivar and Nonabokra, a salt-tolerant, but low yielding cultivar were treated with water (control) or 250 mM NaCl or 20% polyethyleneglycol-6000 for 4 and 8 h. The protein was analyzed by in vitro DNA pol λ activity assay, in-gel activity assay and Western blot analysis. DNA pol λ was not detected in dry seeds, but enhanced after imbibition and detectable from low level to high level during subsequent germination steps. Both salinity and dehydration stress led to the enhancement of the activity and protein level of DNA pol λ, as compared to control tissues. This is the first evidence of the salinity or dehydration stress induced enhancement of DNA pol λ activity in the plumules of rice (Oryza sativa L.) cultivars.


Subject(s)
DNA-Directed DNA Polymerase/analysis , DNA-Directed DNA Polymerase/physiology , Germination/genetics , Oryza/genetics , Oryza/growth & development , Salinity , Seeds/growth & development , Sodium Chloride , Stress, Physiological
18.
Electron. j. biotechnol ; 17(2): 95-101, Mar. 2014. ilus, graf, tab
Article in English | LILACS | ID: lil-714279

ABSTRACT

Background Weedy rice (Oryza sativa L.) is a noxious form of cultivated rice (O. sativa L.) associated with intensive rice production and dry seeding. A cost-efficient strategy to control this weed is the Clearfield rice production system, which combines imidazolinone herbicides with mutant imidazolinone-resistant rice varieties. However, imidazolinone resistance mutations can be introgressed in weedy rice populations by natural outcrossing, reducing the life span of the Clearfield technology. Timely and accurate detection of imidazolinone resistance mutations in weedy rice may contribute to avoiding the multiplication and dispersion of resistant weeds and to protect the Clearfield system. Thus, highly sensitive and specific methods with high throughput and low cost are needed. KBioscience's Allele Specific PCR (KASP) is a codominant, competitive allele-specific PCR-based genotyping method. KASP enables both alleles to be detected in a single reaction in a closed-tube format. The aim of this work is to assess the suitability and validity of the KASP method for detection in weedy rice of the three imidazolinone resistance mutations reported to date in rice. Results Validation was carried out by determining the analytical performance of the new method and comparing it with conventional allele-specific PCR, when genotyping sets of cultivated and weedy rice samples. The conventional technique had a specificity of 0.97 and a sensibility of 0.95, whereas for the KASP method, both parameters were 1.00. Conclusions The new method has equal accuracy while being more informative and saving time and resources compared with conventional methods, which make it suitable for monitoring imidazolinone-resistant weedy rice in Clearfield rice fields.


Subject(s)
Oryza/genetics , Plants, Genetically Modified , Herbicide Resistance/genetics , DNA/isolation & purification , Polymerase Chain Reaction , Sensitivity and Specificity , DNA Primers , Alleles , Plant Weeds , Genotype , Imidazoles , Mutation
19.
Indian J Exp Biol ; 2014 Mar; 52(3): 237-251
Article in English | IMSEAR | ID: sea-150354

ABSTRACT

Rice cultivation under aerobic condition not only saves water but also opens up a splendid scope for effective application of beneficial root symbionts in rice crop unlike conventional puddled rice cultivation where water logged condition acts as constraint for easy proliferation of various beneficial soil microorganisms like arbuscular mycorrhizal (AM) fungi. Keeping these in view, an in silico investigation were carried out to explore the interaction of hydrogen phosphate with phosphate transporter protein (PTP) from P. indica. This was followed by greenhouse investigation to study the response of aerobic rice to Glomus fasciculatum, a conventional P biofertilizer and P. indica, an alternative to AM fungi. Computational studies using ClustalW tool revealed several conserved motifs between the phosphate transporters from Piriformospora indica and 8 other Glomus species. The 3D model of PTP from P.indica resembling “Mayan temple” was successfully docked onto hydrogen phosphate, indicating the affinity of this protein for inorganic phosphorus. Greenhouse studies revealed inoculation of aerobic rice either with P. indica, G. fasciculatum or both significantly enhanced the plant growth, biomass and yield with higher NPK, chlorophyll and sugar compared to uninoculated ones, P. indica inoculated plants being superior. A significantly enhanced activity of acid phosphatase and alkaline phosphatase were noticed in the rhizosphere soil of rice plants inoculated either with P. indica, G. fasciculatum or both, contributing to higher P uptake. Further, inoculation of aerobic rice plants with P. indica proved to be a better choice as a potential biofertilizer over mycorrhiza.


Subject(s)
Aerobiosis , Computer Simulation , Mycorrhizae/genetics , Oryza/genetics , Oryza/parasitology , Phosphate Transport Proteins/genetics , Phosphates/metabolism , Plant Roots/genetics , Plant Roots/microbiology , Plant Shoots , Rhizosphere , Soil Microbiology , Water
20.
Electron. j. biotechnol ; 16(5): 11-11, Sept. 2013. ilus, tab
Article in English | LILACS | ID: lil-690471

ABSTRACT

Background: In order to evaluate the variation among different rice types, the genetic diversity in a rice collection composed by 59 breeding lines, 23 landraces, 18 weedy rice lines, and 35 introduced lines that collected from countries worldwide was analyzed using 134 simple sequence repeat markers. Results: In total, 1264 alleles were identified (average, 9.43 per locus). Rare alleles made up a large portion (58.4%) of the detected alleles, and 29 unique alleles associated with rice accessions were also discovered. A model-based structural analysis revealed the presence of three subpopulations. The genetic relationships revealed by the neighbour-joining tree method were fairly consistent with the structure-based membership assignments for most of the accessions. A total of 105 accessions (79.5%) showed a clear relationship to each cluster, while the remaining 27 accessions (20.5%) were categorized as admixtures. Linkage disequilibrium (LD) patterns and distributions are of fundamental importance for genome-wide association mapping. The mean r² value for all intrachromosomal loci pairs was 0.1286. The LD between linked markers decreased with the genetic distance between pairs of linked loci. Conclusions: These results will provide an effective aid for future allele mining, association genetics, mapping and cloning gene(s), germplasm conservation, and improvement programs.


Subject(s)
Oryza/genetics , Genetic Variation , Linkage Disequilibrium , Microsatellite Repeats , Alleles , Genetics, Population , Genotype
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