Acid Polyacrylamide Gel Electrophoresis Research Articles

PBOX-sRNA-seq uncovers novel features of miRNA modification and identifies selected 5'-tRNA fragments bearing 2'-O-modification.

The concomitant cloning of RNA degradation products is a major concern in standard small RNA-sequencing practices. This not only complicates the characterization of bona fide sRNAs but also hampers cross-batch experimental replicability and sometimes even results in library construction failure. Given that all types of plant canonical small RNAs possess the 3' end 2'-O-methylation modification, a new small RNA sequencing (sRNA-seq) method, designated as PBOX-sRNA-seq, has been developed specifically to capture this modification. PBOX-sRNA-seq, as its name implies, relies on the sequential treatment of RNA samples with phenylboronic acid-polyacrylamide gel electrophoresis (PBA-PAGE) and sodium periodate (NaIO4) oxidation, before sRNA library construction and sequencing. PBOX-sRNA-seq outperformed separate treatments (i.e. PBA-PAGE only or NaIO4 only) in terms of the depletion of unmethylated RNA species and capture 2'-O-modified sRNAs with extra-high purity. Using PBOX-sRNA-seq, we discovered that nascent miRNA-5p/-3p duplexes may undergo mono-cytidylation/uridylation before 2'-O-methylation. We also identified two highly conserved types of 5'-tRNA fragments (tRF) bearing HEN1-independent 2'-O modification (mainly the 13-nt tRF-5aAla and the 26-nt tRF-5bGly). We believe that PBOX-sRNA-seq is powerful for both qualitative and quantitative analyses of sRNAs in plants and piRNAs in animals.

Alleles at the Gli-A3 locus in groups of ukrainian winter common wheat cultivars of different origin

Aim. The aim of the study was to analyze the diversity and frequencies of alleles at the minor gliadin locus Gli-A3 in groups of common winter wheat cultivars developed in different breeding institutions of Ukraine in different periods of time. Methods. Acid polyacrylamide gel electrophoresis of gliadins was carried out. To identify the Gli-A3 allele of the cultivar Myronivska storichna, segregation in a sample of F2 seeds from crossing with the cultivar Bezosta 1 was analyzed. Results. Alleles at Gli-A3 were identified in 511 Ukrainian cultivars. In addition to the alleles a-d, a new allele Gli-A3e encoding two omega-gliadins was identified in Myronivska storichna. The alleles a and b predominate in the total group of cultivars. Differences in the allele composition and frequencies were revealed between some groups of cultivars. A significant reduction in the frequency of Gli-A3b was detected for the groups of the Plant Breeding and Genetics Institute (PBGI) and the V. Ya. Yuryev Plant Production Institute (IPP) cultivars released after 2010. Conclusions. The frequencies of the predominant alleles a and b are similar in the groups of the Central Forest-Steppe cultivars in different periods of breeding. An increase in the frequency of the allele a was noted for the groups of PBGI (the Steppe) and IPP (the Eastern Forest-Steppe) cultivars, which may indicate its adaptive value under conditions of an increase in the average annual temperature in these zones.

A new target for improving wheat end-use quality.

This article is a Commentary on Liu et al. (2023), 239: 87–101.

A Molecular Mechanism to Explain the Nickel-Induced Changes in Protamine-like Proteins and Their DNA Binding Affecting Sperm Chromatin in Mytilus galloprovincialis: An In Vitro Study.

Nickel is associated with reproductive toxicity, but little is known about the molecular mechanisms of nickel-induced effects on sperm chromatin and protamine-like proteins (PLs). In the present work, we analyzed PLs from Mytilus galloprovincialis by urea-acetic acid polyacrylamide gel electrophoresis (AU-PAGE) and SDS-PAGE and assessed their binding to DNA by Electrophoretic Mobility Shift Assay (EMSA) after exposing mussels to 5, 15, and 35 µM NiCl2 for 24 h. In addition, a time course of digestion with MNase and release of PLs from sperm nuclei by the NaCl gradient was performed. For all exposure doses, in AU-PAGE, there was an additional migrating band between PL-III and PL-IV, corresponding to a fraction of PLs in the form of peptides detected by SDS-PAGE. Alterations in DNA binding of PLs were observed by EMSA after exposure to 5 and 15 µM NiCl2, while, at all NiCl2 doses, increased accessibility of MNase to sperm chromatin was found. The latter was particularly relevant at 15 µM NiCl2, a dose at which increased release of PLII and PLIII from sperm nuclei and the highest value of nickel accumulated in the gonads were also found. Finally, at all exposure doses, there was also an increase in PARP expression, but especially at 5 µM NiCl2. A possible molecular mechanism for the toxic reproductive effects of nickel in Mytilus galloprovincialis is discussed.

Characterization of a Wheat-Dasypyrum breviaristatum Chromosome Addition and Its Derived Progenies Carrying Novel Dasypyrum-Specific Gliadin Genes

The construction of the 28-chromosome karyotype of Dasypyrum breviaristatum was undertaken using multicolor non-denaturing fluorescent in situ hybridization (ND-FISH) and Oligo-FISH painting protocols. A novel wheat-D. breviaristatum line D2138 contained 44 chromosomes including a pair of D. breviaristatum 6VbS.2VbL translocation chromosomes. Individual F2 and F3 progenies of a cross between D2138 with wheat lines CM62, MY11 and JM22, respectively, were characterized using ND-FISH and molecular markers. A relatively high chromosome alteration rate within wheat and D. breviaristatum 6VbS and 2VbL was observed in the three progeny populations, suggesting that chromosome 6VbS.2VbL has a gametocidal-like gene. The different types of translocation and deletion lines allowed localization of D. breviaristatum-specific gliadin coding genes on sub-telomeric regions of 6VbS by PCR and acid polyacrylamide gel electrophoresis analysis. The positive effect of the D. breviaristatum 6VbS on agronomic and quality characters was also demonstrated. The new wheat-D. breviaristatum 6VbS and 2VbL translocation lines will be useful as novel germplasm for breeding purposes.

Molecular Cytogenetic Characterization of Novel 1RS.1BL Translocation and Complex Chromosome Translocation Lines with Stripe Rust Resistance.

Rye is the most important source for the genetic improvement of wheat. In this study, two stable wheat-rye primary 1RS.1BL translocation lines, RT855-13 and RT855-14, were selected and identified by acid polyacrylamide gel electrophoresis (A-PAGE), co-dominant PCR, and multi-color fluorescence in situ hybridization (MC-FISH) from the progeny of the crossing of the wheat cultivar Mianyang11 and a Chinese rye Weining. When more than two independent, simple reciprocal translocations are involved in a carrier, they are defined as complex chromosome translocations (CCT). The MC-FISH results also indicated that CCT occurred in RT855-13; namely that, besides 1RS.1BL translocation chromosomes, there are other two pairs of balanced reciprocal translocations. It was demonstrated that the interchange between a distal segment of 4B and long arm of 3D occurred in the RT855-13. The novel translocation chromosomes in wheat were recorded as 3DS.4BSDS and 3DL-4BSPS.4BL. Reports about CCT as a genetic resource in plant breeding programs are scarce. Both lines expressed high resistance to Puccinia striiformis f. sp. tritici, which are prevalent in China and are virulent on Yr9, and the CCT line RT855-13 retained better resistance as adult plants compared with RT855-14 in the field. Both lines, especially the CCT line RT855-13, exhibited better agronomic traits than their wheat parent, Mianyang11, indicating that both translocation lines could potentially be used for wheat improvement. The results also indicated that the position effects of CCT can lead to beneficial variations in agronomic and resistant traits, making them a valuable genetic resource to wheat breeding programs.

Genetic Diversity and Classification of Chinese Elite Foxtail Millet [<i>Setaria italica</i> (L.) P. Beauv.] Revealed by Acid-PAGE Prolamin

Arid and semi-arid regions of China account for more than half of the country. Because of drought resistance and high nutritive value, elite foxtail millet (Setaria Italica (L.) P. Beauv.) is one of the most important cereal crops in China. Evaluation of germplasm and genetic diversity of foxtail millet is still in its infancy, but prolamin could play an important role as a protein marker. To investigate the genetic diversity and population structure of foxtail millet from different ecological zones of China, 90 accessions of foxtail millet were collected from three major ecological areas: North, Northwest, and Northeast China. The prolamin contents were examined by acid polyacrylamide gel electrophoresis (acid-PAGE). Five to twenty-two prolamin bands appeared in tested varieties, of which were polymorphic, so prolamin patterns of foxtail millet varieties can be used in variety identification and evaluation. Structure analysis identified six groups, which matches their pedigree information but not their geographic origins. This indicated a high degree (87.78%) of consistency with a phylogenetic classification based on SSR. The results showed prolamin banding patterns were an effective method for analyzing foxtail millet genetic variability.

Grain quality indices in common wheat lines with introgressions of chromosome 1U from Aegilops biuncialis Vis.

Aim. The aim of this study was to analyze grain quality indices in winter common wheat lines with introgressions of chromosome 1U from Aegilops biuncialis Vis. marked by storage protein loci. Methods. Acid polyacrylamide gel electrophoresis and SDS-electrophoresis of storage proteins were performed to identify introgressions. Grain quality indices (SDS sedimentation volume and grain protein content) were analyzed in lines with introgressed chromosome 1U or its arm 1UL, as well as in the cultivars Panna and Bezostaya 1. Results. SDS-sedimentation volume in the cultivars and lines depended on year’s conditions. The studying of the lines during two years has demonstrated that the presence of the allele at the high molecular weight glutenin subunit locus Glu-U1 from Ae. biuncialis was associated with a high volume of SDS-sedimentation SDS30 (higher than that in the cultivar Bezostaya 1). The introgressive lines show high grain protein content. Conclusions. The effect of the allele at the high molecular weight glutenin subunit locus Glu-U1 from Ae. biuncialis on SDS-sedimentation value is similar to that of the high-quality allele Glu-B1al. The lines with the introgressed allele at Glu-U1 from Ae. biuncialis are valuable initial material for breeding for quality.Keywords: Triticum aestivum, Aegilops biuncialis, high molecular weight glutenin subunits, SDS-sedimentation, protein content.

Analysis of gliadin patterns and diversity in Triticum polonicum L. accessions from Ethiopia

Gliadins from 25 accessions represented by 350 individual seed samples were analysed by acid-polyacrylamide gel electrophoresis (A-PAGE) with the objective of identifying gliadin band patterns and examine the extent of diversity in Triticum polonicum L. collections from Ethiopia. Seventy polymorphic bands and 68 different patterns were identified. Eighteen different mobility bands and 16 patterns were identified in ω-gliadin region, 22 bands and 20 patterns in γ-gliadin region, 12 bands and 22 patterns in β-gliadin region and 18 bands and 10 patterns in α-gliadin region. The average genetic diversity calculated from the data of the four gliadin zones of the analysed samples was 0.15. The γ region have the highest diversity (H = 0.193), followed by ω regions (H = 0.177) and β region (H = 0.168) and the lowest diversity was observed in α region (H = 0.127). Cluster analysis based on genetic distances resulted in grouping of the analysed accessions in to seven main groups. Though the level of diversity was relatively lower than other tetraploid wheat species from Ethiopia, the findings are indicative of the existence of variation in the collections which can be exploited for wheat improvement.

Assessment genetic diversity of einkorn genotypes (Triticum monococcum L.) by gliadin electrophoresis

The genetic diversity of gliadins in twenty two einkorn accessions preserved under long-term seed storage condition in the National gene bank of Bulgaria were evaluated, using acid polyacrylamide-gel electrophoresis (Acid-PAGE). In total, 64 polymorphic bands and 22 gliadin patterns were identified. Thirty four different mobility bands and 21 gliadin patterns were identified in the ω-gliadin zone, 12 bands and 16 patterns were noted in the γ-gliadins, 17 patterns and 12 mobility bands were found for β-gliadins and six bands with five different α -gliadin patterns were determined. The genetic diversity index (H) was the highest for ω-gliadins (0.950), followed by β-gliadins (0.924) and γ- (0.914), respectively and the lowest value was detected in α-gliadin patterns (0.120). Cluster analysis based on the UPGMA method and Nei and Li similarity coefficients classified all the genotypes into 3 main groups. No relationships between genetic diversity, geographic origin and the genotypes were observed. The results of cluster analysis justify the high level of genetic variation among investigated einkorn accessions.

The effect of mutations in the alleles Gli-B1b and Gli-B1l on grain quality indices of common wheat

Aim. The aim of this study was to analyze quality indices in mutants at gliadin loci developed on the basis of the common wheat cultivar Bezostaya 1. Methods. Acid polyacrylamide gel electrophoresis and SDS-electrophoresis of storage proteins were performed to check mutations. Grain quality indices (SDS sedimentation volume, grain hardness, seed plumpness, and grain protein content) were analyzed: Results. Both mutants at Gli-R1 with the intensified secalin component and with the changed mobility of the secalin component showed lower grain hardness in comparison with the respective non-mutant lines. The mutation of the allele Gli-B1b causing the absence of synthesis of the g-gliadin and the minor w-gliadin resulted in the decrease in grain hardness and in the increase in the SDS-sedimentation volume. Seeds of the Gli-B1b mutant with the absence of synthesis of the major w-gliadin were less plump and showed higher protein content than in the non-mutant line. Conclusions. The effects of mutations of the allele Gli-B1b associated with the absence of certain gliadin components and Gli-R1 mutations on grain quality indices were revealed.
 Keywords: Triticum aestivum, gliadins, secalins, SDS-sedimentation, grain hardness.

Genotypic determination of human group A rotaviruses from Goa and Meghalaya states, India

IntroductionRotavirus is the leading cause of diarrhoea in young children in India, responsible for an estimated 21357 mean numbers of deaths in 2010. Various genotypes of rotaviruses evolved due to mutational changes have been recognized. In this study, we determined the genotypes of rotaviruses involved in diarrhea in Goa and Meghalaya states of India. MethodsThe dsRNA of rotaviruses was extracted from stool samples and detected by Ribonucleic Acid-Polyacrylamide gel electrophoresis (RNA PAGE) and Reverse transcription-polymerase Chain Reaction (RT-PCR) targeting the partial VP7 gene. The full length VP7 and partial VP4 genes of rotavirus strains were amplified by RT-PCR followed by nucleotide sequencing. The RotaC classification tool was used to determine the genotypes. ResultsThe positivity of rotavirus by PAGE and RT-PCR was observed to be 43.10% and 39.65% in Goa and 38% and 36% in Meghalaya, respectively. Though long electrophoretic profile was appeared to be the most predominant rotavirus type in circulation in these two states, 96% of long and 84.61% short electropherotype profiles could be detected by RT-PCR. The dsRNA of rotavirus extracted from 36 samples could be transcribed and amplified by beg9end9 primers for G genotyping, while, 41 by con3con2 primers for P genotyping. G1P[8] and G1P[6] genotypes were commonly circulated in Goa and G1P[8] and G1P[4] genotypes in Meghalaya. On nucleotide analysis, 6 samples from Goa showed G1 genotype specificity, while, 3 showed P[8] specificity indicating the G1P[8] rotavirus circulating in Goa. In Meghalaya state, 3 strains showed P[8] and 2 showed P[4] genotype specificity. The majority of the G and P genotypes were closely related to each other and G1 genotypes appeared in two separate clusters, while, P[8] and P[4] appeared in the respective clusters. ConclusionThe circulation of G1P[8], G1P[6] genotypes in Goa and the presence of G1P[8] and G1P[4] genotypes in Meghalaya was observed.

Special features of transmission of markers for Aegilops biuncialis Vis. Chromosome 1U in common wheat hybrids

Aim. The wild wheat relative Aegilops biuncialis Vis. is a potential source of new storage protein alleles for enriching the common wheat gene pool. We have produced the wheat material from direct crossing of common wheat with Crimean samples of Ae. biuncialis followed by backcrossing with wheat. Using storage proteins as genetic markers, lines with introgressions of chromosome 1U have been selected. The objective of the investigation was to study the transmission of markers for chromosome 1U in the hybrid from crossing the common wheat cultivar Bezostaya 1 with a line carrying chromosome 1U. Methods. F2 seeds from the cross of the common wheat cultivar Besostaya 1 and the line NVG41 carrying Ae. biuncialis chromosome 1U were analyzed. Storage proteins encoded by Gli-U1 and Glu-U1 served as markers for chromosome 1U. Gliadins were analyzed by acid polyacrylamide gel electrophoresis by the procedure of Kozub et al. (2009). Electrophoresis of total seed proteins, including high-molecular-weight glutenin subunits, was carried out by the procedure of Laemmli (1970).Results. Among the F2 seeds analyzed, we identified four classes of genotypes with respect to the markers Gli-U1 and Glu-U1: 1) with complete chromosome 1U, 2) with the 1UL arm only, 3) with the 1US arm only, 4) without chromosome 1U. In the F1 hybrid NVG41 × Bezostaya 1, Ae. biuncialis chromosome 1U was transmitted with an increased frequency (with respect to the marker Glu-U1 and the simultaneous presence of the markers Gli-U1 and Glu-U1). The frequency of centric misdivision of chromosome 1U (univalent) in the F1 hybrid amounted about 9 %. This resulted in a significantly lower number of seeds with the 1US arm only (2 %) than that with the 1UL arm (6 %).Conclusions. In the progeny of F1 hybrids with Ae. biuncialis univalent 1U, a lower frequency of genotypes with the 1US arm only as compared with the 1UL arm only can be observed at the grain stage. This could be due to the loss of telocentrics with the 1US arm at gamete formation or reduced viability of genotypes with 1US only at the gamete stage or after zygote formation.Manuscript received 02.04.2020

Modified acid-PAGE method for rapid screening and phenotyping of wheat gliadin mutant lines

Acid-polyacrylamide gel electrophoresis (A-PAGE) is used to phenotype different varieties of wheat based on their gliadin profiles. The family of gliadin proteins is a major component of wheat gluten. Gluten is the major determinant of the unique viscoelastic property of wheat dough that is necessary in the production of important food products including bread, cake, cookies and pasta. However, several gliadin proteins are also known to be causal agents in triggering human immunogenic responses that lead to several gluten-related health risks like celiac disease and wheat-dependent exercise-induced anaphylaxis. Therefore, research to identify wheat lines with reduced levels of immunogenic proteins is being vigorously pursued in several laboratories around the world. Unfortunately, no commercial A-PAGE gels are currently available for cereal researchers to use for separating wheat gliadins. This work reports the development of an easy-to-use A-PAGE protocol to resolve gliadins with high reproducibility and resolution to screen and phenotype gliadin deficient lines in wheat.•This acetic acid based A-PAGE method with urea utilizes commercially available reagents and materials to make gel casting simpler and more efficient.•It can be used to phenotype different wheat varieties to establish purity and to identify mutants of wheat with altered gliadin protein profiles.

Mutants at gliadin loci on the basis of the common wheat cultivar Bezostaya 1

Aim. The aim of this study was to isolate and propagate mutants at gliadin loci developed on the basis of the common wheat cultivar Bezostaya 1. Methods. We searched for spontaneous and gamma-irradiation induced mutations at gliadin loci among the progeny of F1 and F2 plants from crosses between near-isogenic lines by gliadin loci on the basis of the cultivar Bezostaya 1, including lines with the wheat-rye 1BL.1RS translocation. To identify mutations, we performed acid polyacrylamide gel electrophoresis and SDS-electrophoresis of storage proteins. Results. On the basis of the common wheat cultivar Bezostaya 1, five mutants (six mutations) at gliadin loci were isolated and propagated, four of which were described for the first time. Three mutations occurred at the Gli-R1 locus involved in the wheat-rye 1BL.1RS translocation (the loss of secalins, intensification of a secalin component, and increased mobility of a secalin component). Two mutations were identified in the allele Gli-B1b, one caused the null-allele at the Gli-A2 locus. Conclusions. The material of mutants is of importance for studying the role of certain groups of storage proteins and their components in quality determination, as well as mechanisms of regulation of storage protein synthesis.
 Keywords: Triticum aestivum, gliadin, secalin, mutation, 1BL.1RS translocation.

Allelic variation at the gliadin coding loci of improved Ethiopian durum wheat varieties

The objective of this study was to determine gliadin allele compositions of 20 improved Ethiopian durum wheat varieties using acid-polyacrylamide gel electrophoresis (A-PAGE). Each block of co-dominantly inherited polypeptides encoded by gliadin loci were identified and their genetic diversities were estimated using statistical analyses. A total of 30 electrophoretic blocks were identified at five major gliadin loci. In addition, four novel gliadin blocks were identified. Gli-B1 and Gli-A2 loci had higher numbers of gliadin alleles (nine and ten, respectively) compared to other loci. Alleles Gli-A1c on chromosome 1A, Gli-B1c on chromosome 1B, Gli-A2a, and Gli-A2o on chromosome 6A, and Gli-B2h on chromosome 6B had maximal frequencies in their corresponding loci. Varieties were classified into three main clusters and one singleton based on genetic distances of detected gliadin alleles. These results indicate that Ethiopian durum wheat varieties are genetically diverse with unique allele compositions at gliadin-coding loci.

Molecular Cytogenetic Characterization of Novel Wheat-rye T1RS.1BL Translocation Lines with High Resistance to Diseases and Great Agronomic Traits.

Rye has been used worldwide as a source for the genetic improvement of wheat. In this study, two stable wheat-rye primary T1RS.1BL translocation lines were selected from the progeny of the crossing of the wheat cultivar Mianyang11-1 and a Chinese local rye variety, Weining. These two novel translocation lines were identified by molecular cytogenetic analysis. PCR results, multi-color fluorescence in situ hybridization (MC-FISH), and acid polyacrylamide gel electrophoresis (A-PAGE) indicated that both new translocation lines harbor a pair of T1RS.1BL translocation chromosomes, and have been named RT828-10 and RT828-11, respectively. The cytogenetic results also indicated that the pSc119.2 signals of 5AL were absent in both lines along with the pSc119.2 signals of 4AL of RT828-11. When inoculated with different stripe rust and powdery mildew isolates, both lines expressed high resistance to Puccinia striiformis f. sp. tritici and Blumeria graminis f. sp. tritici pathotypes, which are prevalent in China and are virulent on Yr9 and Pm8. The line RT828-11 also exhibited excellent agronomic traits in the field. The present study indicates that this rye variety may carry untapped variations that could potentially be used for wheat improvement.

Detection and Genotypic Characterisation of Rotavirus from Piglets and In-Contact Children of Assam, a North-Eastern State of India

Rotavirus (RV) has been established as the most common cause of acute gastroenteritis among human infants and the neonates of most farm animal species throughout the world. In this study, a total of 409 faecal/stool samples from porcine (0–8 months) and in-contact children (8 months–5 years) were screened for RV by ribonucleic acid-polyacrylamide gel electrophoresis (RNA-PAGE) and reverse transcriptase polymerase chain reaction (RT-PCR) targeting VP7 and VP4 gene individually. Irrespective of species, a total of 120 (29.33%) were found positive for group A rotavirus RVA consisting of 65 (29.28%) from piglets and 55 (29.41%) from in-contact children, forming a typical 4:2:3:2 band pattern in RNA-PAGE. All the RNA-PAGE-positive samples were also confirmed by RT-PCR. G and P typing were done targeting VP7 and VP4 gene in nested-multiplex PCR where G3P[6], G3P[7], G9P[6], G9P[7] genotypes in porcine and G1P[6], G1P[8], G9P[6], G9P[8] genotypes in humans were encountered. The close interaction among piglets and in-contact children appeared to facilitate inter-species transmission of RV. Isolation of porcine RV genotype G3 from human samples indicated the zoonotic importance of RV. The most common genotypes found circulating were G9P[6] in porcine and G1P[8] in human population.

Molecular identification of ω-secalin gene expression activity in a wheat 1B/1R translocation cultivar

ω-Secalin was an important factor influencing processing quality of wheat 1BL/1RS translocations. On the basis of four ω-secalin gene sequences cloned from Lankao 906 (a wheat cultivar with 1BL/1RS translocation) with putative transcription activity, a pair of primers with suitable restriction endonucleases added at their 5′ ends were designed to amplify the mature protein-coding regions of the four genes. After digestion with restriction endonucleases, the amplified products were ligated into the prokaryotic expression vector pET30a(+). The prokaryotically expressed recombinant proteins and gliadin isolated from the Lankao 906 seed were analyzed on the same acid polyacrylamide gel electrophoresis. All four prokaryotically expressed secalin bands had corresponding seed-expressed gliadin bands. The four corresponding gliadin bands were confirmed to be the expression products of the four ω-secalin genes by liquid chromatography tandem mass spectrometry (LC-MS/MS). This conclusion was further confirmed because the four ω-secalin bands could be detected in all 14 wheat 1BL/1RS translocation cultivars used in the study, although there was some interference for the detection of one ω-secalin band from nearby wheat gliadin bands. The sequence information of ω-secalin genes with expression activity will be helpful for improving the processing quality of wheat with 1BL/1RS translocations by using RNA interference method to silence the expression of the ω-secalin genes.

Molecular Cytogenetic Characterization of New Wheat-Rye 1R(1B) Substitution and Translocation Lines from a Chinese Secale cereal L. Aigan with Resistance to Stripe Rust.

Secale cereale L. has been used worldwide as a source of genes for agronomic and resistance improvement. In this study, a stable wheat-rye substitution line and 3 primary 1RS.1BL translocation lines were selected from the progeny of the crossing of the Chinese local rye Aigan variety and wheat cultivar Mianyang11. The substitution and translocation lines were identified by molecular cytogenetic analysis. PCR results, fluorescence in situ hybridization and acid polyacrylamide gel electrophoresis indicated that there were a pair of 1R chromosomes in the substitution line which have been named RS1200-3, and a pair of 1RS.1BL translocation chromosomes in the other 3 translocation lines, which have been named RT1163-4, RT1217-1, and RT1249. When inoculated with stripe rust isolates, these 4 lines expressed high resistance to several Puccinia striiformis f. sp Tritici pathotypes that are virulent on Yr9. Moreover, the different response pattern of resistance among them suggested that the diversity of resistance genes for wheat stripe rust exists in the rye. These 4 lines also showed better agronomic performances than their wheat parent. The GS indices also showed the genetic diversity of the 1RS which derived from same rye variety. The present study indicates that rye cultivars may carry untapped variations that could potentially be used for wheat improvement.