INDUCED MUTATIONS IN TaASN-A2 REDUCE FREE ASPARAGINE CONCENTRATION IN THE WHEAT GRAIN

Acrylamide is a neurotoxin and probable carcinogen formed as a processing contaminant during baking and production of different foodstuffs, including bread products. The amino acid asparagine is the limiting substrate in the Maillard reaction that produces acrylamide, so developing wheat varieties with low free asparagine concentrations in the grain is a promising approach to reduce dietary acrylamide exposure. A candidate gene approach was used to identify chemically-induced genetic variation in ASPARAGINE SYNTHETASE 2 (ASN2) genes that exhibit a grain-specific expression profile. In field trials, durum and common wheat lines carrying asn-a2 null alleles exhibited reductions in free asparagine concentration in their grains of between 9 and 34% compared to wild-type sister lines. These plants showed no significant differences in spikelet number, grain size and weight, germination or baking quality traits. These non-transgenic variants can be deployed without restriction in elite wheat germplasm to reduce acrylamide-forming potential with no negative impacts on quality or agronomic performance.

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Inhibition of lateral shoot formation by RNA interference and chemically induced mutations to genes expressed in the axillary meristem of Nicotiana tabacum L.

BMC Plant Biology ◽

10.1186/s12870-021-03008-3 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Kaori Hamano ◽

Seiki Sato ◽

Masao Arai ◽

Yuta Negishi ◽

Takashi Nakamura ◽

...

Keyword(s):

Rna Interference ◽

Shoot Formation ◽

Field Trials ◽

Induced Mutations ◽

Lateral Shoot ◽

Leaf Production ◽

Chemically Induced ◽

Lateral Shoots ◽

Lateral Branches ◽

Primary Lateral

Abstract Background Lateral branches vigorously proliferate in tobacco after the topping of the inflorescence portions of stems for the maturation of the leaves to be harvested. Therefore, tobacco varieties with inhibited lateral shoot formation are highly desired by tobacco farmers. Results Genetic inhibition of lateral shoot formation was attempted in tobacco. Two groups of genes were examined by RNA interference. The first group comprised homologs of the genes mediating lateral shoot formation in other plants, whereas the second group included genes highly expressed in axillary bud primordial stages. Although “primary” lateral shoots that grew after the plants were topped off when flower buds emerged were unaffected, the growth of “secondary” lateral shoots, which were detected on the abaxial side of the primary lateral shoot base, was significantly suppressed in the knock-down lines of NtLs, NtBl1, NtREV, VE7, and VE12. Chemically induced mutations to NtLs, NtBl1, and NtREV similarly inhibited the development of secondary and “tertiary” lateral shoots, but not primary lateral shoots. The mutations to NtLs and NtBl1 were incorporated into an elite variety by backcrossing. The agronomic characteristics of the backcross lines were examined in field trials conducted in commercial tobacco production regions. The lines were generally suitable for tobacco leaf production and may be useful as new tobacco varieties. Conclusion The suppressed expression of NtLs, NtBl1, NtREV, VE7, or VE12 inhibited the development of only the secondary and tertiary lateral shoots in tobacco. The mutant lines may benefit tobacco farmers by minimizing the work required to remove secondary and tertiary lateral shoots that emerge when farmers are harvesting leaves, which is a labor-intensive process.

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Allelic variants for Waxy genes in common wheat lines bred at the Lukyanenko National Grain Center

Vavilov Journal of Genetics and Breeding ◽

10.18699/vj19.566 ◽

2019 ◽

Vol 23 (7) ◽

pp. 910-915

Author(s):

E. R. Davoyan ◽

L. A. Bespalova ◽

R. O. Davoyan ◽

E. V. Agaeva ◽

G. I. Bukreeva ◽

...

Keyword(s):

Molecular Markers ◽

Bread Wheat ◽

Common Wheat ◽

Triticum Aestivum L ◽

Null Alleles ◽

Wheat Varieties ◽

Allelic Variants ◽

Breeding Material ◽

Wheat Lines ◽

Mutant Forms

This article presents the results of a molecular marker-assisted study of allelic variants of Wx genes in common wheat (Triticum aestivum L.) lines. The study was carried out as part of the work on the transfer of null alleles of the genes Wx-A1, Wx-B1, and Wx-D1 to the varieties of soft wheat and creation of breeding material with modified activities of the main enzymes involved in amylose biosynthesis. The lines were obtained at the Department of Breeding and Seed Production of Wheat and Triticale, National Center of Grain named after P.P. Lukyanenko, by crossing mutant forms carrying inactive (null) alleles of genes Wx-A1, Wx-B1, and Wx-D1 with bread wheat cultivars. The molecular markers selected for the study allowed identification of valuable breeding material carrying both single null alleles of Wx genes and their combinations in its genome. A combination of two null alleles (Wx-A1b + Wx-D1b) was detected in 30 lines. The presence of three null alleles (Wx-A1b + Wx-B1b + Wx-D1b), which corresponded to fully Wx wheat, was found in one line. We selected 37 lines that combined the presence of the Wx-B1e allele with the Wx-A1b and Wx-D1b null alleles. The Wx-A1b + Wx-B1e combination was identified in 26 lines, and 24 lines carried the combination of alleles Wx-B1e + Wx-D1b. The mutant forms PI619381, PI619384, and PI619386 were identified as carriers of the functional Wx-B1e allele. The Wx-A1b and Wx-B1e alleles could have been transferred to the studied lines from the donors used or from the Starshina and Korotyshka varieties, respectively. The mutant forms used in the crosses are donors of the Wx-B1b and Wx-D1b alleles. The use of molecular markers chosen by us for identification of the allelic state of the Wx-A1, Wx-B1, and Wx-D1 genes can provide grounds for marker-assisted selection for this trait. Selected lines found to possess null alleles of the Wx genes are applicable in breeding programs aimed at the improvement of technological qualities of grain and raise of bread wheat varieties with modified starch properties.

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VIRULENCE OF THE NORTH CAUCASIAN POPULATION OF PUCCINIA GRAMINIS PERS. F. SP. TRITICI

Vestnik of the Russian agricultural science ◽

10.30850/vrsn/2021/2/40-45 ◽

1970 ◽

pp. 40-45

Author(s):

G. V. Volkova ◽

Е. V. Gladkova ◽

O. O. Miroshnichenko

Keyword(s):

High Efficiency ◽

Caucasian Population ◽

Puccinia Graminis ◽

North Caucasus ◽

Wheat Varieties ◽

Caucasus Region ◽

Pathogen Virulence ◽

The North ◽

New Varieties ◽

Wheat Lines

The aim of the study was to monitor the virulence of Puccinia graminis Pers. f. sp. tritici in the North Caucasus. The objectives of the study were to collect P. graminis infectious material from sown winter wheat varieties and evaluate the long-term dynamics of the pathogen virulence in the North Caucasus region in 2014-2019. As a result, an analysis of the virulence of the stem rust pathogen population of wheat collected in Krasnodar, Stavropol Territories, and Rostov Region was carried out. 81 mono-empty mushroom isolates were isolated and differentiated. The genes Sr5, Sr31, Sr38 were characterized by high efficiency. On the lines with the genes Sr7b, Sr8b, Sr9f, Sr9g, Sr10, Sr11, Sr12, Sr13, Sr14, Sr21, Sr22, Sr23, Sr26, Sr29, Sr32, Sr33, S35, Sr37, SrDp2, SrWLD, a variation in the virulence frequencies of P. graminis was observed. Significant changes (in the direction of increasing occurrence) in the North Caucasian population 2014-2019 the pathogen was noted in the frequency of clones virulent to wheat lines with resistance genes Sr11, Sr21, Sr22, Sr26, Sr32, Sr33. A decrease in the frequency of clones virulent to Sr8b, Sr9g, Sr10, Sr12, Sr14, Sr35. At approximately the same level, the occurrence of clones virulent to the genes Sr6, Sr7a, Sr8а, Sr9a, Sr9b, Sr9d, Sr9e, Sr13, Sr15, Sr16, Sr17, Sr19, Sr20, Sr24, Sr25, Sr27, Sr30, Sr36, Sr39, Sr40, Sr44, SrGt, SrTmp. Effective genes that have shown their resistance to P. graminis in the seedling phase are proposed for use in breeding in southern Russia to create new varieties of wheat.

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Triticum polonicum L. as potential source material for the biofortification of wheat with essential micronutrients

Plant Genetic Resources ◽

10.1017/s1479262118000394 ◽

2018 ◽

Vol 17 (03) ◽

pp. 213-220 ◽

Cited By ~ 4

Author(s):

Teresa Bieńkowska ◽

Elżbieta Suchowilska ◽

Wolfgang Kandler ◽

Rudolf Krska ◽

Marian Wiwart

Keyword(s):

Durum Wheat ◽

Common Wheat ◽

Principal Component ◽

Small Scale ◽

Wheat Varieties ◽

Triticum Polonicum ◽

Iron And Zinc ◽

Modern Wheat ◽

Wheat Lines ◽

Source Materials

AbstractThe grain of modern wheat cultivars has a significantly lower mineral content, including the content of copper, iron, magnesium, manganese, phosphorous, selenium and zinc. For this reason cereal breeders, are constantly searching for new genetic sources of minerals that are essential in human nutrition. Triticum polonicum, which is grown on a small scale in Spain, southern Italy, Algeria, Ethiopia and warm regions of Asia, deserves special attention in this context. The micronutrient and macronutrient content of T. polonicum versus T. durum and T. aestivum was compared in this study. Polish wheat grain was characterized by the significantly highest content of phosphorus (4.55 g/kg), sulphur (1.82 g/kg), magnesium (1.42 g/kg), zinc (49.5 mg/kg), iron (39.1 mg/kg) and boron (0.56 mg/kg) as well as a low content of aluminium (only 1.04 mg/kg). The macronutrient profile of most T. polonicum lines differed completely from that of common wheat and durum wheat. The principal component analysis supported discrimination of seven Polish wheat lines with a particularly beneficial micronutrient profile (P2, P3, P5, P7, P9, P22 and P25). These lines were characterized by the highest content of copper, iron and zinc, as well as the lowest concentrations of strontium, aluminium and barium which are undesirable in food products. The above lines can be potentially applied as source materials for breeding new wheat varieties. The results of this study indicate that Polish wheat could be used in genetic biofortification of durum wheat and common wheat.

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Construction and Characterization of Mutations within theKlebsiella mrkD1P Gene That Affect Binding to Collagen Type V

Infection and Immunity ◽

10.1128/iai.67.4.1672-1676.1999 ◽

1999 ◽

Vol 67 (4) ◽

pp. 1672-1676 ◽

Cited By ~ 7

Author(s):

Tricia A. Sebghati ◽

Steven Clegg

Keyword(s):

Collagen Type ◽

Gene Products ◽

Induced Mutations ◽

Binding Properties ◽

Collagen Binding ◽

Chemically Induced ◽

Collagen Type V ◽

Type V ◽

Type 3

ABSTRACT The fimbria-associated MrkD1P protein mediates adherence of type 3 fimbriate strains of Klebsiella pneumoniae to collagen type V. Currently, three different MrkD adhesins have been described in Klebsiella species, and each possesses a distinctive binding pattern. Therefore, the binding abilities of mutants possessing defined mutations within themrkD 1P gene were examined in order to determine whether specific regions of the adhesin molecule were responsible for collagen binding. Both site-directed and chemically induced mutations were constructed within mrkD 1P, and the ability of the gene products to be incorporated into fimbrial appendages or bind to collagen was determined. Binding to type V collagen was not associated solely with one particular region of the MrkD1Pprotein, and two classes of nonadhesive mutants were isolated. In one class of mutants, the MrkD adhesin was not assembled into the fimbrial shaft, whereas in the second class of mutants, the adhesin was associated with fimbriae but did not bind to collagen. Both hemagglutinating and collagen-binding activities were associated with the MrkD1P molecule, since P pili and type 3 fimbriae carrying adhesive MrkD proteins exhibited identical binding properties.

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Identification of theVERNALIZATION 4gene reveals the origin of spring growth habit in ancient wheats from South Asia

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1514883112 ◽

2015 ◽

Vol 112 (39) ◽

pp. E5401-E5410 ◽

Cited By ~ 66

Author(s):

Nestor Kippes ◽

Juan M. Debernardi ◽

Hans A. Vasquez-Gross ◽

Bala A. Akpinar ◽

Hikment Budak ◽

...

Keyword(s):

South Asia ◽

Rna Binding ◽

Growth Habit ◽

Regulatory Region ◽

Proximal Region ◽

Induced Mutations ◽

Wheat Varieties ◽

Density Mapping ◽

Chromosome Arm ◽

Delayed Flowering

Wheat varieties with a winter growth habit require long exposures to low temperatures (vernalization) to accelerate flowering. Natural variation in four vernalization genes regulating this requirement has favored wheat adaptation to different environments. The first three genes (VRN1–VRN3) have been cloned and characterized before. Here we show that the fourth gene,VRN-D4, originated by the insertion of a ∼290-kb region from chromosome arm 5AL into the proximal region of chromosome arm 5DS. The inserted 5AL region includes a copy ofVRN-A1that carries distinctive mutations in its coding and regulatory regions. Three lines of evidence confirmed that this gene isVRN-D4: it cosegregated withVRN-D4in a high-density mapping population; it was expressed earlier than otherVRN1genes in the absence of vernalization; and induced mutations in this gene resulted in delayed flowering.VRN-D4was found in most accessions of the ancient subspeciesTriticum aestivumssp.sphaerococcumfrom South Asia. This subspecies showed a significant reduction of genetic diversity and increased genetic differentiation in the centromeric region of chromosome 5D, suggesting thatVRN-D4likely contributed to local adaptation and was favored by positive selection. Three adjacent SNPs in a regulatory region of theVRN-D4first intron disrupt the binding ofGLYCINE-RICH RNA-BINDING PROTEIN 2(TaGRP2), a known repressor ofVRN1expression. The same SNPs were identified inVRN-A1alleles previously associated with reduced vernalization requirement. These alleles can be used to modulate vernalization requirements and to develop wheat varieties better adapted to different or changing environments.

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Rumen digestibility in dairy cows of starch in near-isogenic lines of wheat

Proceedings of the British Society of Animal Science ◽

10.1017/s1752756200002453 ◽

1999 ◽

Vol 1999 ◽

pp. 90-90

Author(s):

P.C. Garnsworthy ◽

J. Wiseman

Keyword(s):

Near Isogenic Lines ◽

Limited Information ◽

Wheat Varieties ◽

Isogenic Lines ◽

Relative Value ◽

Metabolisable Energy ◽

Growing Conditions ◽

The Uk ◽

Wheat Lines ◽

Agronomic Conditions

Wheat is a good source of carbohydrates for ruminants, and recent low prices in the UK suggest that usage is likely to increase. However, there is a shortage of information on the digestibility of wheat in the rumen. Such information is vital for predicting the relative value of wheat as a source of fermentable metabolisable energy or by-pass starch. Digestibility is likely to be affected by growing conditions and genetics. Genetic differences are found between wheat varieties, but comparisons of named varieties yield limited information because many characteristics vary simultaneously. This problem can be overcome by using near-isogenic lines of wheat that vary only in a limited number of known characteristics. The objective of this study was to determine the rumen digestion characteristics of different near-isogenic wheat lines grown under the same agronomic conditions.

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Chemically induced mutations in a MutaMouse reporter gene inform mechanisms underlying human cancer mutational signatures

Communications Biology ◽

10.1038/s42003-020-01174-y ◽

2020 ◽

Vol 3 (1) ◽

Cited By ~ 2

Author(s):

Marc A. Beal ◽

Matthew J. Meier ◽

Danielle P. LeBlanc ◽

Clotilde Maurice ◽

Jason M. O’Brien ◽

...

Keyword(s):

Human Cancer ◽

Published Data ◽

Induced Mutations ◽

Lung Cancers ◽

Human Cancers ◽

Chemically Induced ◽

Mutation Pattern ◽

Environmental Causes ◽

Next Generation Sequencing Ngs

AbstractTransgenic rodent (TGR) models use bacterial reporter genes to quantify in vivo mutagenesis. Pairing TGR assays with next-generation sequencing (NGS) enables comprehensive mutation pattern analysis to inform mutational mechanisms. We used this approach to identify 2751 independent lacZ mutations in the bone marrow of MutaMouse animals exposed to four chemical mutagens: benzo[a]pyrene, N-ethyl-N-nitrosourea, procarbazine, and triethylenemelamine. We also collected published data for 706 lacZ mutations from eight additional environmental mutagens. We report that lacZ gene sequencing generates chemical-specific mutation signatures observed in human cancers with established environmental causes. For example, the mutation signature of benzo[a]pyrene, a carcinogen present in tobacco smoke, matched the signature associated with tobacco-induced lung cancers. Our results suggest that the analysis of chemically induced mutations in the lacZ gene shortly after exposure provides an effective approach to characterize human-relevant mechanisms of carcinogenesis and propose novel environmental causes of mutation signatures observed in human cancers.

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Reaction of wheat varieties to infection with barley yellow dwarf virus and prospects for resistance breeding

Czech Journal of Genetics and Plant Breeding ◽

10.17221/32/2009-cjgpb ◽

2009 ◽

Vol 45 (No. 2) ◽

pp. 45-56 ◽

Cited By ~ 7

Author(s):

O. Veškrna ◽

J. Chrpová ◽

V. Šíp ◽

T. Sedláček ◽

P. Horčička

Keyword(s):

Winter Wheat ◽

Spring Wheat ◽

Barley Yellow Dwarf Virus ◽

Field Trials ◽

Yellow Dwarf ◽

Dwarf Virus ◽

Wheat Varieties ◽

Barley Yellow Dwarf ◽

Virus Content ◽

Yellow Dwarf Virus

The reaction of winter and spring wheat to infection with barley yellow dwarf virus (BYDV-PAV) was evaluated in three-year small-plot field trials on 71 wheat varieties registered in the Czech Republic and at two locations for two years on 63 selected potential sources of resistance. Disease symptoms (VSS) were visually recorded using a 0–9 scale and the percent reduction of grain weight per spike (GWS-R) was measured on twenty plants per plot. The evaluation showed that among the registered varieties of winter and spring wheat no variety had a high resistance to BYDV (with VSS lower than 3.5). GWS-R ranged between 24% and 60%. Higher variability in VSS was detected for the registered varieties of spring wheat compared to winter wheat. Among the registered varieties of winter wheat, Saskia, Rialto, Meritto, Rexia, and Svitava, as well as the spring wheat Leguan, received the best long-term evaluations. The highest level of resistance was detected for the PSR 3628 line (a hybrid of wheat and couch-grass), but in connection with a low agronomic value. The WKL91-138 line of spring wheat and some varieties (lines) with the detected moderate level of resistance, in particular, could offer good prospects for use in breeding. The presence of the Bdv2 gene was expressed only in the reduction of virus content on the 11<sup>th</sup> day after inoculation. Nevertheless, genotypes carrying this gene were evaluated in field trials as susceptible or very susceptible to infection with the Czech PAV isolate. Similarly, the presence of the Bdv1 gene detected with the help of WMS130 marker was no assurance of an increased level of resistance to BYDV. Hybridological analyses of crosses with the WKL91-138 line showed a polygenic nature of inheritance. Thus, the marker-assisted selection does not obviously promise success without a focus on detecting a larger number of QTLs.

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