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Showing 77 results for Darvish


Volume 0, Issue 0 (ARTICLES IN PRESS 2024)
Abstract

Climate change (CC) is one of the major challenges of our time that impacts rangelands regionally and globally. The rising vulnerability among pastoralists highlights the need to prioritize resilience thinking. Pastoralists' resilience refers to the ability of rangeland businesses to endure, adapt to, and remain flexible in the face of threats or challenges. This research was conducted with the primary goal of analyzing the factors that influence resilience from the perspective of pastoralists in Tehran province under CC conditions. This research was both goal-oriented and exploratory in methodology. The study sample consisted of 317 pastoralists selected through stratified random sampling. The data collection tool was a researcher-made questionnaire. Software SmartPLS was used for data analysis. The validity of the questionnaire was assessed using the average variance extracted, while its reliability was established by calculating composite reliability and Cronbach's alpha. Data were analyzed using the structural equation modeling technique with Smart PLS software. The structural equation modeling indicated that economic, institutional, ecological, physical, social, educational and extensional and individual factors had the greatest impact on Pastoralists' Resilience under Climate Change (PRCC) conditions. These factors explained 75.5% of the PRCC conditions.
 

Volume 2, Issue 1 (9-2011)
Abstract

Lipase is used in the production of detergents, cosmetics, pharmaceuticals, flavour enhancers and foods. The lipase of yeast Yarrowia lipolytica can be used for production of important class of chemical intermediates in the pharmaceutical industry. Lipase production depends on media composition and environmental conditions. Y. lipolytica DSM 3286 strain was cultured on media containing different organic and inorganic nitrogen sources. Lipase production was investigated by measuring biomass and lipase activity was detected by ρ-nitrophenyl laurate (PNPL) spectrophotometric assay method at various times within a period of 7 days. In this study, the effect of different nitrogen sources was investigated on Y. lipolytica DSM 3286 lipase production. The maximal lipase production (34.7 U/ml after 48 h) was detected in medium containing yeast extract as nitrogen source. The optimum temperature and pH of the enzyme activity were 37 °C and 7, respectively. The final goal of this study is to develop and optimize lipase production by Y. lipolytica for use in pharmaceutical industry.

Volume 3, Issue 1 (3-2014)
Abstract

Black stem is one of the most important fungal diseases of sunflower which is caused by Phoma macdonaldii. This research was conducted to clarify the interactions between a few breeder lines and wild-type accessions of sunflower with seven isolates of Phoma macdonaldii, the causal agent, under controlled conditions. The experiment was carried out in randomized complete block design with three replications. Each replication consisted of 30 seedlings. Twenty micro liters of spore suspension was deposited at the intersection of the cotyledon petiole and hypocotyl of four-leaf-stage sunflower seedlings as well. Three, five and seven days after inoculation, seedlings were scored on a 1-9 scale for percentage of necrotic area. Highly significant differences were observed among genotypes, isolates and their interactions for disease severity 7 days after inoculation based on AUDPC (Area Under Disease Progress Curve) values. Two models of GGE biplot including Isolate-based and genotype-based models were used to study the pathogenicity of the isolates and susceptibility of sunflower, respectively. Isolate-focused biplot revealed that there was a considerable difference between virulence of isolates. Based on genotype-focused biplot model, accessions including 665 Iowa, 1012 Nebraska, 211 Illinois and 1016 Nebraska were more resistant to studied isolates of P. macdnaldii. Results revealed that GGE biplot approach could lead to good understanding about interactions between sunflower genotypes and Phoma macdonaldii isolates.  

Volume 3, Issue 2 (6-2014)
Abstract

The severe epidemics of Fusarium head blight (FHB) as a devastating disease of cereal crops has occurred on wheat in North and Northwest Iran in recent years. The in vitro production of Deoxynivalenol (DON) was qualitatively evaluated in 41 Fusarium isolates collected from wheat heads associated with the scab disease, in Moghan area/Northwest Iran. Infected wheat heads were collected during 2004-2007. The isolation of causal agents was carried out using standard methods. According to morphological characteristics and using valid descriptions, all isolates belonged to Fusarium graminearum species complex and F. culmorum of which the former was dominant. In order to evaluate the potential of DON production in isolates, this mycotoxin was extracted and qualitatively examined by TLC method. The quantification of DON was achieved using HPLC method. TLC results indicated that 54.5% of studied isolates produced DON but there was no significant relationship between this property and cultivars or sub-regions or years. Also based on HPLC analysis, maximum content of DON was detected in F. graminearum isolated from cv. Izen green from Moghan Agro-industry company fields in 2004 at the rate of 5827.11 µgkg-1. The results of present study show that DON mycotoxin is produced at various contents by F. graminearum isolates on different cultivars and from different origins/ years. Since DON plays a role in pathogenesis and is of paramount importance in contamination of wheat grains, these results give a better insight into the significance of this disease in Northwest Iran.  

Volume 4, Issue 3 (fall 2023)
Abstract

Aims: Home businesses have a historical background. With the advent of the virtual space, many people have started to create a business in their home environment for various reasons. This change has had many visible and invisible effects not only in the home and family, but also in the city. The upcoming research is focused on determining the ranking of the components and social dimensions of sustainable development under the influence of home businesses in order to determine their priority.
Methods: Descriptive-analytical research method with quantitative method and qualitative results and the results are based on the opinions of 35 experts based on the results of a specialized questionnaire. In conclusion, the 25 components and 9 indicators of the social subcategory of sustainable urban development based on the 2030 sustainable development document, using a structured questionnaire and its analysis with EXCEL and SPSS software, tries to make changes related to division and prioritization.
findings: The components “Social Empowerment, literacy  , Quality Education , Social Responsibilities , Manpower Development, Social Confidence, Amount of Crimes, Neighborhood Development, Social Streaming” and the indicators “Education, Sustainable Cities and Communities, Social Security , Social Capital” are heavily influenced by home businesses .
Conclusion: The main results showed that home businesses, both online and offline, directly and indirectly have a significant impact on the social dimension of sustainable urban social development, And it is suggested to planning for sustainability goals of countries.


Volume 4, Issue 4 (Winter 2021)
Abstract

Research subject: In recent years, due to limited water resources and the extraordinary increase in nitrates in the environment, efforts to remove and control in order to benefit from the natural adsorbents have been made. Although according to the negatively charged surface of bentonite particles, absorbent needs improvement.
Research approach: In the current study, the adsorption of nitrate columns by the modified calcium montmorillonite adsorbent was investigated. Furthermore, In order to change the surface load and increase the adsorption efficiency, three-step acid leaching, oxidation layering, and loading of the cationic surfactant hexadecyltrimethylammonium bromide on the adsorbent were performed. Molecular interaction and crystallography of pure montmorillonite and synthetic nano-adsorbent (ACZ) were characterized by Fourier transform infrared spectroscopy and X-ray analysis. Moreover, the morphology of ACZ nano adsorbents was evaluated using Transmission electron microscopy and scanning electron microscopy.
Main results: Nanoparticle compaction and less access to pores and cavities in the fixed bed column reduced the adsorbent capacity inside the column compared to the discontinuous system.
The results showed that an increase in inlet concentration from 80 to 150 mg/L increased the adsorption capacity from 67.39 to 88.25 mg/g. Reducing the inlet flow rate increased the penetration time, interaction, and greater access to the binding sites for nitrate ions and finally improved the column performance and increased the inlet flow rate reduced the adsorption capacity and breakthrough time. Therefore, the adsorption of nitrate ions by the stage of internal mass transfer is controlled and depends on the duration of interaction and the possibility of penetration into the active sites. With increasing the bed height from 4.2 to 9 cm, there was a significant increase in adsorption capacity from 60.608 to 77.167 mg/g. The effect of detergents and recovery showed an absorption column; After 3 leaching steps, acid leaching played an important role in increasing column recovery. Experimental data with correlation coefficients of R2>0.95 corresponded to Thomas and Yoon-Nelson kinetic models.
In this study, the ACZ nano adsorbent column for rapid removal of nitrate ions from aqueous solutions was introduced and for use in reusable systems was proposed.

 

Volume 5, Issue 0 (0-2005)
Abstract

In this paper, we used a shape matching algorithm to recognize Farsi digits. For each sampled point on the contour of a shape, we obtain a descriptor showing the distribution of the other points of the contour, with respect to this point. Based on these descriptors, we find the corresponding points of the two contours and take the sum of their distances as a dissimilarity measure between two shapes. Then we define a geometric transformation that maps the sampled points of the one shape to the corresponding points of the other shape. The bending energy of this transform is taken as the second dissimilarity measure between two shapes. We optimized the parameters of the matching algorithm for the recognition of Farsi digits and used the method of minimum distance from the class prototypes for the recognition. In a test on a set of 1288 digits, we obtained a recognition rate of 89.9%. This result was obtained without any post processing

Volume 5, Issue 2 (8-2014)
Abstract

This study was conducted to evaluate genetic variation among 70 sunflower recombinant inbred lines (RIL) derived from the crosses PAC2 × RHA266 together with parents based on seed morphological traits by using a rectangular lattice design with two replications. Seed morphological such as kernel length, kernel width, kernel diameter, 100-kernel weight, percentage of hull, percentage of dehulled kernel and seed yield per plant was measured. Analysis of variance revealed significant differences among lines for the studied traits. The highest coefficient of phenotypic variation was observed for seed yield per plant (23.42) and the lowest one was observed for percentage of dehulled kernel (1.37). The highest heritability was observed for 100-kernel weight (0.995) and kernel width (0.990) and the lowest one was observed for the yield per plant (0.521). The highest correlation coefficients were observed between kernel diameter and kernel width (0.908). Principal component analysis reduced the seed characteristics traits to 2 components explaining 81% accumulative variance. By using Ward clustering method based on seed morphological traits the 72 studied sunflower lines were classified into six groups.

Volume 6, Issue 2 (11-2015)
Abstract

This study was designed to investigate the genetic diversity and relationships between yield and related traits in oily sunflower lines. 152 sunflower lines collected from different parts of the world were investigated at completely randomized design with nine replications on Urmia University in 1391 under pot conditions. 14 agro-morphological traits including plant height, stem diameter, number of leaves, leaf length, leaf width, petiole length, head diameter, 100 seed weight, head dry weight, , seed yield per plant, number of days from planting to flowering, and number of days from planting to maturity, dehulled kernel to whole kernel and harvest index were measured. Analysis of variance revealed significant differences among genotypes for all studied traits. Among the traits, the highest coefficient of phenotypic variation was observed for seed yield per plant (56.30), harvest index (44.4) and head dry weight (35.44). The results of correlation analysis showed that there is significant and positive correlation between seed yield per plant with most of the studied traits. Results of sequential path analysis revealed that the variables such as number of leaves, dehulled kernel to whole kernel, head diameter, and plant height were arranged as the first-order variables. Cluster analysis subdivided the genotypes into 4 groups. The maximum distance were observed between the genotype from groups 3 and 4 (28.30).

Volume 6, Issue 22 (10-2018)
Abstract

Human needs Formalizes each new type of language. In eighty decade expanded Argot in human every speaking that targeted religions, polity & gender taboos and mixed with modern problems. Resulting of cause of cultural studded may be analysis by Cultural Studies .For lexicography field impractical linguistics noticed only inner entry of same lexicon and fields of historic, sociology, politic arn’t notable but cultural studies with interdisciplinary way and equal vision to formal language & common opens the atmosphere to show the informal language in formal institutional. This essay attempts with content analysis survey literal & topic eighty decade in five sours of books & lexicons that have sow Argot. For finds cause of Argot are expanding free time entering IT & technology be hidden in virtual spade & expand of Soap Opera in Eight Decade. Without misconstruing survey enters of Argot words without taboo to national language can boost formal language.

Volume 7, Issue 1 (6-2016)
Abstract

Drought is known as an important factor limiting growth and product of field crops in most parts of the world and Iran. In the present work, the genetic diversity of 100 inbred lines of sunflower was investigated based on agro-morphogical characters with simple lattic design with two replications under normal and drought stress conditions. Combined analysis of variance revealed significant differences among lines for most of studied traits. Uneder normal condition, the highest coefficient of genetic variation was observed for stem diameter and the lowest one observed for relative water content. In drought stress condition, the highest coefficient of genetic variation was observed for seed yield per plant and the lowest one observed for days to flowering. The results of correlation analysis showed that there is significant and positive correlation between seed yield per plant with most of the studied traits in both stress conditions. Stepwise regression analysis revealed that under drought stress condition 73.9 percent of seed yield per plant variation was expailed by heed diameter, leaf width and petiol length and in normal condition 73.6 yield grain per plant variation explained by head diameter and plant height. Cluster analysis grouped lines into 4 clusters in each one of normal and drought conditions but the distruption of lines within groups were differents depending to stress environment that present the genetic variability for drought tolerance in sunflower lines.
Zeinab Tabanejad, Sorena Darvish, Zeinab Borjian Boroujeni, Seyed Saeed Asadi, Morteza Mesri, Omid Raiesi, Muhammad Ebrahim Getso, Mahdi Zareei,
Volume 7, Issue 2 (Spring 2021)
Abstract

Backgrounds: A novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has now spread to all countries of the world, including Iran. Although anti-SARS-CoV-2 antibodies may be identified in patients using immunological methods with sufficient sensitivity and specificity, the conclusive diagnosis of the disease is made using the molecular RT-PCR method. A population-based seroepidemiological survey was conducted to quantify the proportion of the exposed population with SARS-CoV-2 antibodies and evaluate whether the antibodies are a marker of total or partial immunity compared to the population that remains susceptible to the virus.
Material & Methods: This cross-sectional study was conducted to investigate the seroprevalence of COVID-19 in Valiasr, Sajad, and Ghaem hospitals in Tehran, the capital of Iran, from April to the end of October 2020. Clotted and heparinized blood specimens (2mL) were collected from the patients. The serum and plasma were separated and stored at −80 °C until use. Anti-SARS-CoV-2 IgG and IgM antibodies were examined in the serum samples of 1375 in-patients admitted to the hospitals using ELISA kits. The obtained data were analyzed using SPSS software Ver.22.0 by employing statistical tests such as Chi-square and Fisher’s exact tests. A p-value <.05 was considered as significant.
Findings: In total, 1375 participants were enrolled in this study, and SARS‐CoV‐2 antibodies were detected in 291 patients using IgM‐IgG antibody assay. Among the seropositive patients studied, 187 were male (64.3%), and 104 were female (35.7%) (p<.05). The mean age of the patients was 49±8.4 years; the majority of whom (27%) were in the age group of 31-40 years. Also, the lowest frequency of infected cases was related to the age group of 1-10 years (p <.05). The seroprevalence of SARS‐CoV‐2 IgM or IgG antibodies was determined to be 21.2%. Diabetes mellitus was the most common underlying disease among SARS‐CoV‐2 patients [p=.05; Odd Ratio=1.61(0.90-2.91)].
Conclusion: The use of conventional serological assays, such as the enzyme-linked immunoassay (ELISA), for detecting specific IgM and IgG antibodies in SARS‐CoV‐2 patients has a high-throughput advantage while minimizing false-negative results obtained using the RT-PCR method. In this study, the seroprevalence of SARS-CoV-2 antibodies was determined to be 21%. Control of diabetes, among other influential factors, plays an important role in the management and control of COVID-19.

Volume 7, Issue 3 (Special Issue 2016)
Abstract

One of the newest methods in plant breeding programs is mapping quantitative trait loci (QTL) with molecular markers. In order to identify QTL associated with some chemical traits such as chlorine, nicotine, sugar concentrations and ash in oriental tobacco, a population of 55 recombinant inbred lines coming from the cross Basma seres 31 × SPT406 were evaluated for above mentioned traits. QTL mapping was performed using linkage map developed on 103 recombinant inbred lines by 64 molecular markers including 14 SSR, 24 ISSR and 26 retrotransposone. The linkage map is composed of 7 linkage groups (LGs). Composite interval mapping revealed 5 QTLs associated with studied traits. Phenotypic variation explained by identified QTLs varied between 0.34 and 0.70. Any QTL was not detected for sugar concentration in tobacco leaves. Common markers between some of studied traits can be due to linkage or pleiotropic effects. The common markers lead to increase the efficiency of marker-assisted selection in plant breeding programs via simultaneously selection for several traits.

Volume 9, Issue 1 (Winter 2018)
Abstract

Aims: The aim of the present study was to map the morphological traits in Iranian Basil accessions (Oscillum Oscillos) by Inter Simple Sequence Repeats (ISSRs) markers. 
Materials & Methods: In this experimental study, 50 Iranian basil accessions from different geographical regions were used and the experiment was based on a completely randomized design. Extracting DNA and PCR was performed with 12 ISSR primers for Basil accessions. Components of variance, general heritability, and genetic and phenotypic variation coefficients were calculated by formula. Bayesian method, linear mixed model as well as Minitab 17, DARwin 5, Structure 2.3.3, Tassel 3, and SPSS 20 software were used.  Findings: There was a positive correlation between the majority of traits for basil accessions. The highest coefficient of genetic variation was observed in stem diameter and internode length and the lowest was observed in flower number. Heritability varied between 3.63% and 94.24%. Foutrteen loci with 7 traits were recognized. The range of phenotypic changes varied from 3% to 29%. The highest number of locus was obtained for stem diameter traits and the lowest was obtained for lateral branch number. Six loci were specifically associated with only one trait and other loci were common in traits. The phenotypic variation varied between 17% and 29%. 
Conclusion: Traits have a wide variety in Basil accessions and there is a positive correlation between the majority of them. The heritability of the traits varies from 3.63% to 94.24% and the range of the phenotypic changes varies from 3% to 29%. The highest number is for stem diameter traits and lowest is for lateral branch number. Six loci are specifically associated with only one trait and other loci are common in traits. The phenotypic variation varies between 29% ‐17%. 


Volume 9, Issue 1 (Winter 2020)
Abstract

Aims: Monitoring of the fish biomass is one of the basic principal of fisheries management, but ornamental and reef fish stocks, because of difficulty of estimating their abundance, have been less studied than others. The aim of this study was to estimate the standing biomass of ornamental and reef fishes in Larak Island, in the Strait of Hormuz.
Materials &Methods: Standing biomass of the fish species was assessed seasonally using Underwater Visual Census Method (UVCm) in coral reefs and  mesophotic coral reefs in Larak Island throughout 2018 and 2019. Two popular methods in UVCm (belt transect and stationary point) were used based on topography of sea bottom. The confidence interval of estimated standing biomass is calculated using bootstrapping method.
Findings: The standing biomass of ornamental and reef fishes is estimated as 2522.18, 5222.17 and 1325.15(Kg.) in Site 1, Site 2 and Site 3, that are located in 3-15meters depth. The standing biomass at Site 4, was estimated as 884.13kg. The minimum were observed in summer, also the result showed  that the standing biomass in summer was significantly lower than other seasons (P <0.05). In addition, the temporal diagnostic test showed that population structure of fish in the spring, autumn, and winter seasons was similar but significantly different from the population structure in summer.
Conclusion: The less of standing biomass in summer season can be affected  by seasonal migrations of fish in tropical and subtropical waters to deeper waters, in order to trade of the stresses caused by temperature fluctuations.
 

Volume 9, Issue 2 (Spring 2018)
Abstract

Aims: Sclerotinia is an important fungal disease of sunflower in Iran that affects its yield. The present study was conducted with the aim of evaluating proline content, total protein, and protein electrophoresis pattern in sunflower (Helianthus annuus L.) in response to sclerotinia (Sclerotinia sclerotiorum) disease.
Materials and Methods: In this experimental study, proline content, total protein, and protein electrophoresis pattern in sunflower lines (C39 and C100) were compared with control group during different times after inoculation of the lines with the Sclerotinia fungal isolates (SSU107 and SSKH41) under controlled conditions and as a factorial based on completely randomized design (CRD). Separation and isolation of total proteins extracted by sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE). The date were analyzed by SPSS 22 software, using multivariate analysis of variance and Tukey test.
Findings: Resistant line C39 in all of the time periods after being infected had higher proline compared with control and other groups. The total protein of all control plants was higher than that of infected plants with both fungal isolates. Fungal infection accumulated low molecular weight proteins in both lines, so that some proteins in the resistant and some proteins in susceptible lines were produced and removed, respectively.
Conclusion: Resistant line C39 in sunflower infected with fungal isolate SSU107 Sclerotinia sclerotiorum has the highest proline content. Fungal infection, especially in resistant lines, leads to a reduction in total protein levels and the accumulation of low molecular weight proteins in resistant and susceptible lines.


Volume 9, Issue 3 (Summer 2018)
Abstract

Aims: Sunflower (Helianthus annuus L.) is mainly cultivated for the extraction of edible oil, and Sclerotinia sclerotiorum is a pathogen in sunflower fields. The aim of this study was to indetify markers associated with resistance to Sclerotnia Scleritiorum diseases in sunflower, using association analysis.
Materials and Methods: In the present experimental research, a population including 100 lines of oily sunflower was cultivated. Traits such as contamination progress after 4, 8, and 12 days, 100 seeds weight of contaminated and non-contaminated plants, contaminated and non-contaminated plant yield, 100 seeds weight loss, and yield loss were studied. The molecular profiles of germplasm were prepred with 30 microsatellite primer pairs. Genetic structure analysis of population was performed based on Bayesian model.
Findings: The highest coefficient of variation was related to the yield loss (86.41%) and weight loss (78.48%), and the lowest was contamination progression after 8 and 12 days (26.47% and 20.44%), respectively. Based on the mixed linear model (MLM), 6 microsatellite markers related to traits were identified at the level of p≤0.01. The highest number of markers was associated with contamination progression after 8 days. The P733, P807, and P1256 markers were simultaneously associated with 3 traits.
Conclusion: Four lines including RHA274, H100A-83HR4, B45-03, and Iranian line with code 28 were identified with different genetic origins and high resistance levels. According to the general linear model (GLM) and MLM, 24 and 15 SSR markers are related to the traits, respectively. The P733, P807, and P1256 markers are simultaneously associated with 3 traits.


Volume 9, Issue 3 (5-2020)
Abstract

Brown spot, caused by Bipolaris oryzae, is a devastating disease of rice which can cause yield loss in most rice-growing regions of the world. Breeding for disease resistance is the preferred strategy of managing brown spot. Hence, identification and subsequent development of disease resistance in rice genotypes are crucial. The field resistance of 95 rice genotypes to brown spot was evaluated under water and fertilizer stress during 2017 and 2018. Partial resistance was assessed through reaction type (disease rating) and epidemiological parameters estimates i.e. final brown spot index, area under disease progress curve and apparent infection rate. Disease rating, brown spot index, and area under disease progress curve detected differences in the responses of rice genotypes to disease under field condition, which could be used to study brown spot resistance. Among the genotypes tested, 22 genotypes were resistant to moderately resistant (23.16%) while majority were moderately susceptible to susceptible (76.84%). A significant correlation between leaf angle and area under disease progress curve indicated positive influence of leaf erectness on severity of brown spot disease. Results showed that leaf infection did not significantly affect the number of filled grains per panicle or hundred seed weight, but caused yield decline by decreasing the number of productive tillers. Nevertheless, the infection of rice genotypes from flowering to ripening stages decreased the number of filled grains per panicle and grain weight. The resistant genotypes identified in this study can be exploited for future rice breeding programs to develop promising resistant lines in management of the brown spot disease.
 


Volume 10, Issue 2 (Spring 2019)
Abstract

Maize (Zea mays L.) is one of the most cultivated crops worldwide, owing to its versatility and wide adaptability, and serves as food, animal feed, and raw material for various industrial products. The purpose of the current research was the classification of maize inbred lines in order to produce hybrid seeds based on agro-morphological traits. Each of 100 maize inbred lines was planted in 6 pots as 6 replications and arranged in completely randomized design in an open area near to greenhouse in 2015. The result of the analysis of variance revealed significant differences among lines for all studied traits. The highest correlation was seen between cob’s length and cob’s weight. Stepwise regression analysis revealed that 66.4% of seed yield per plant variation was determined by cob’s length and cob’s weight. Cluster analysis divided inbred lines into 4 groups. The highest Mahalanobis distance (28.07) was observed between cluster 2 and 4. The result of principal component analysis confirmed the calcification by cluster analysis. The genotypes from groups 2 and 4 can be potentially used as parental lines in hybrid varieties production and development of segregating populations.


Volume 10, Issue 4 (Fall 2019)
Abstract

Revealing DNA sequences is vital for all branches of biological sciences. Next-Generation Sequencing (NGS) is a different approach in this area so that it has created a great evolution in biology science and covers various aspects of genome, transcriptome, epigenome and metagenome-level studies. NGS is considered as a high-performance method for genomic and transcriptomic information analysis in comparison with traditional methods due to providing good genomic coverage, determining each single pairs of bases and eliminating the first generation sequencing disadvantages (Sanger sequencing). Use of NGS has begun since 2005 and 2006, after the commercialization of various apparatus companies such as ABI/SOLiD Illumina, Science Roch/454Life, and Solexa to study the transcriptome of the model and non-model organisms. Recently, RNA sequencing is used widely to identify genes associated with growth and development processes and their expression patterns in response to a variety of biological and non-biological stresses, in various organs and growth stages in different organisms. It helps scientists to determine the amounts of gene expression, differentiation of different isoforms of genes, detection of gene fusions and characterization of small RNA as well as alternative splicing events, duplicate elements, exon of genes, new transcripts, UTRs, SNPs, and somatic mutations. The RNA-seq method typically consists of providing suitable biological samples, isolation of total RNA, enrichment of non-ribosomal RNAs, conversion of RNA to cDNA, construction of a fragment library, selecting size and adding linkers and sequencing on high-throughput sequencing platform, alignment, and assembly of the reads and downstream analysis.


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