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The basic leucine zipper (bZIP) family of genes encode transcription factors that play key roles in plant growth and development. In this study, a total of 92 HvbZIP genes were identified and compared with previous studies using recently released barley genome data. Two novel genes were characterized in this study, and some misannotated and duplicated genes from previous studies have been corrected. Phylogenetic analysis results showed that 92 HvbZIP genes were classified into 10 groups and three unknown groups. The gene structure and motif distribution of the three unknown groups implied that the genes of the three groups may be functionally different. Expression profiling indicated that the HvbZIP genes exhibited different patterns of spatial and temporal expression. Using qRT-PCR, more than 10 HvbZIP genes were identified with expression patterns similar to those of starch synthase genes in barley. Yeast one-hybrid analysis revealed that two of the HvbZIP genes exhibited in vitro binding activity to the promoter of HvAGP-S. The two HvbZIP genes may be candidate genes for further study to explore the mechanism by which they regulate the synthesis of barley starch. Key words: barley, basic leucine zipper, transcription factors, gene interaction, starch synthesis. La famille de genes qui presentent un domaine de glissiere a leucines basique (bZIP) code pour des facteurs de transcription qui jouent des roles cles dans la croissance et le developpement des plantes. Dans ce travail, les auteurs ont identifie un total de 92 genes HvbZIP grace aux plus recentes donnees genomiques chez l'orge et ils les comparent a ceux rapportes precedemment. Deux genes inedits sont rapportes dans ce travail et certaines erreurs d'annotation ou cas de duplication de genes rapportes anterieurement font l'objet ici d'une correction. Une analyse phylogenetique a montre que les 92 genes HvbZIP appartiennent a 10 groupes connus et trois groupes inconnus. La structure des genes et la distribution des motifs au sein de ces trois groupes inconnus suggerent que les genes qui en font partie pourraient avoir des fonctions differentes. Une analyse de l'expression genique indique que les genes HvbZIP presentent differents modes d'expression tant au niveau spatial que temporel. A laide de la qRT-PCR, les auteurs ont identifie plus de 10 genes HvbZIP affichant une expression semblable a celle des genes codant pour lamidon synthase chez l'orge. Une analyse 'un hybride' chez la levure a revele que deux des genes HvbZIP presentaient une activite de liaison in vitro avec le promoteur du gene HvAGP-S. Ces deux genes constituent des candidats pour des etudes futures, pour explorer le mecanisme par lequel ils regulent la synthese de l'amidon chez lorge. [Traduit par la Redaction] Mots-cles : orge, glissiere a leucines basique, facteurs de transcription, interaction genique, synthese de l'amidon., Introduction Transcription factors (TFs) play key roles in the regulation of gene transcription by binding to cis-acting elements of their target genes. Basic region/leucine zipper (bZIP) TFs are one of [...]

In our previous work, a novel high-molecular-weight glutenin subunit (HMW-GS) with an extremely large molecular weight from Aegilops sharonensis was identified that may contribute to excellent wheat (Triticum aestivum) processing quality and increased dough strength, and we further generated HMW-GS homozygous lines by crossing. In this study, we crossed the HMW-GS homozygous line 66-17-52 with 'Chinese Spring' Phl mutant CS phlb to induce chromosome recombination between wheat and Ae. sharonensis. SDS-PAGE was used to identify 19 derived [F.sub.2] lines with the HMW-GSs of Ae sharonensis. The results of non-denaturing fluorescence in situ hybridization (ND-FISH) indicated that lines 6-1 and 6-7 possessed a substitution of both 5D chromosomes by a pair of 1[S.sup.sh] chromosomes. Further verification by newly developed 1[S.sup.sh]-specific chromosome markers showed that these two lines amplified the expected fragment. Thus, it was concluded that lines 6-1 and 6-7 are 1[S.sup.sh](5D) chromosome substitution lines. The 1[S.sup.sh](5D) chromosome substitution lines, possessing alien subunits with satisfactory quality-associated structural features of large repetitive domains and increased number of subunits, may have great potential in strengthening the viscosity and elasticity of dough made from wheat flour. Therefore, these substitution lines can be used for wheat quality improvement and further production of 1[S.sup.sh] translocation lines. Key words: Aegilops sharonensis, substitution line, Ph gene mutant, high-molecular-weight glutenin subunits, molecular markers. Dans leurs travaux precedents, les auteurs ont identifie une nouvelle sous-unite de glutenine de masse moleculaire elevee (HMW-GS) de tres grande masse chez l'Aegilops sharonensis, laquelle pourrait contribuer a produire un ble (Triticum aestivum) dote de meilleures proprietes pour la transformation et d'une meilleure resistance de la pate. Les auteurs ont egalement genere des lignees homozygotes HMW-GS par la voie de croisements. Dans ce travail, les auteurs ont croise la lignee homozygote 66-17-52 avec le mutant Ph1 de Chinese Spring (CS ph1b) pour produire des recombinants chromosomiques entre le ble et l'Ae. sharonensis. Des gels SDS-PAGE ont ete employes pour identifier 19 descendants [F.sub.2] porteurs de HMW-GS de l'Ae. sharonensis. Les resultats d'hybridations in situ en fluorescence en conditions non-denaturantes (ND-FISH) ont revele que les lignees 6-1 et 6-7 presentent une substitution des deux chromosomes 5D par une paire de chromosomes 1[S.sup.sh]. Des analyses additionnelles realisees au moyen de marqueurs specifiques du chromosome 1[S.sup.sh] nouvellement mis au point ont montre que les fragments attendus ont ete obtenus chez ces deux lignees. Les auteurs concluent donc que les lignees 6-1 et 6-7 sont des lignees de substitution 1[S.sup.sh](5D). Ces lignees de substitution chromosomique 1[S.sup.sh](5D) possedent des sous-unites d'origine interspecifique qui presentent des caracteristiques structurales associees a une meilleure qualite, soit la presence de grands domaines repetes et un nombre accru de sous-unites. Celles-ci permettront possiblement d'accroitre la viscosite et l'elasticite de la pate preparee a partir de farine de ble. Ainsi, ces lignees de substitution pourront servir a ameliorer la qualite du ble panifiable ainsi que pour la production de lignees de translocation 1[S.sup.sh]. [Traduit par la Redaction] Mots-cles : Aegilops sharonensis, lignee de substitution, mutant du gene Ph, sous-unites de glutenine de masse moleculaire elevee, marqueurs moleculaires., Introduction High-molecular-weight glutenin subunits (HMW-GSs) are essential in the determination of dough viscosity and elasticity in wheat flour processing (Shewry et al. 2003). HMW-GSs are encoded by the Glu-1 loci, [...]

A completely developed and vigorous root system can provide a stable platform for aboveground plant organs. To identify loci controlling root traits that could be used in wheat (Triticum aestivum L.) breeding, 199 recombinant inbred lines were used to measure and analyze eight root traits. A total of 18 quantitative trait loci (QTL) located on chromosomes 1A, 2A, 2B, 2D, 4B, 4D, 6A, 7A, and 7B were identified. The phenotypic variation explained by these 18 QTL ranged from 3.27% to 11.75%, and the logarithm of odds scores ranged from 2.50 to 6.58. A comparison of physical intervals indicated several new QTL for root traits were identified. In addition, significant correlations between root and agronomic traits were detected and discussed. The results presented in this study, along with those of previous reports, suggest that chromosomes 2 and 7 likely play important roles in the growth and development of wheat roots. Keywords: Triticum aestivum L., recombinant inbred lines, root traits, quantitative trait loci, correlation. Un systeme racinaire bien developpe et vigoureux peut servir d'assise stable aux organes aeriens de la plante. Afin d'identifier des locus contr[delta]lant des caracteres racinaires utiles en amelioration genetique chez le ble (Triticum aestivum L.), 199 lignees recombinantes fixees ont ete employees pour mesurer et analyser huit caracteres racinaires. Au total, 18 QTL, situes sur les chromosomes 1A, 2A, 2B, 2D, 4B, 4D, 6A, 7A et 7B, ont ete identifies. La variation phenotypique expliquee par ces QTL variait entre 3,27 et 11,75%, et les scores LOD variaient entre 2,50 et 6,58. Une comparaison des intervalles physiques a suggere que plusieurs QTL inedits pour des caracteres racinaires ont ete identifies. De plus, des correlations significatives entre des caracteres racinaires et agronomiques ont ete detectees et sont discutees. Les resultats presentes dans cette etude, avec ceux rapportes anterieurement, suggerent que les chromosomes 2 et 7 jouent des roles importants dans la croissance et le developpement des racines chez le ble. [Traduit par la Redaction] Mots-cles: Triticum aestivum L., lignees recombinantes fixees, caracteres racinaires, locus de caracteres quantitatifs, correlation., Introduction Common wheat (Triticum aestivum L.) is an important food crop planted worldwide (Ray et al. 2013). The development of high-yielding wheat varieties with good quality is essential in wheat [...]

A study published in the Plant Biotechnology Journal explores the use of genome editing to increase the resistant starch (RS) and dietary fiber content in barley grains. The researchers targeted five starch synthesis genes using CRISPR/Cas9 technology and successfully generated barley mutants with mutations in one to three of the targeted genes. These mutants exhibited significantly higher levels of amylose, RS, and dietary fiber compared to the control group. The study demonstrates the feasibility of multiplex gene editing for modifying starch and provides a basis for breeding barley with improved health benefits. [Extracted from the article]

Chitin is a long‐chain polymer of β‐1,4‐linked N‐acetylglucosamine that forms rigid microfibrils to maintain the hyphal form and protect it from host attacks. Chitin oligomers are first recognized by the plant receptors in the apoplast region, priming the plant's immune system. Here, seven polysaccharide deacetylases (PDAs) were identified and their activities on chitin substrates were investigated via systematic characterization of the PDA family from Fusarium graminearum. Among these PDAs, FgPDA5 was identified as an important virulence factor and was specifically expressed during pathogenesis. ΔFgpda5 compromised the pathogen's ability to infect wheat. The polysaccharide deacetylase structure of FgPDA5 is essential for the pathogenicity of F. graminearum. FgPDA5 formed a homodimer and accumulated in the plant apoplast. In addition, FgPDA5 showed a high affinity toward chitin substrates. FgPDA5‐mediated deacetylation of chitin oligomers prevented activation of plant defence responses. Overall, our results identify FgPDA5 as a polysaccharide deacetylase that can prevent chitin‐triggered host immunity in plant apoplast through deacetylation of chitin oligomers. [ABSTRACT FROM AUTHOR]

The dynamic balance and distribution of sphingolipid metabolites modulate the level of programmed cell death and plant defence. However, current knowledge is still limited regarding the molecular mechanism underlying the relationship between sphingolipid metabolism and plant defence. In this study, we identified a wheat RNA‐binding protein 1 (TaRBP1) and TaRBP1 mRNA accumulation significantly decreased in wheat after infection by Puccinia striiformis f. sp. tritici (Pst). Knockdown of TaRBP1 via virus‐induced gene silencing conferred strong resistance to Pst by enhancing host plant reactive oxygen species (ROS) accumulation and cell death, indicating that TaRBP1 may act as a negative regulator in response to Pst. TaRBP1 formed a homopolymer and interacted with TaRBP1 C‐terminus in plants. Additionally, TaRBP1 physically interacted with TaGLTP, a sphingosine transfer protein. Knockdown of TaGLTP enhanced wheat resistance to the virulent Pst CYR31. Sphingolipid metabolites showed a significant accumulation in TaGLTP‐silenced wheat and TaRBP1‐silenced wheat, respectively. In the presence of the TaRBP1 protein, TaGLTP failed to be degraded in a 26S proteasome‐dependent manner in plants. Our results reveal a novel susceptible mechanism by which a plant fine‐tunes its defence responses by stabilizing TaGLTP accumulation to suppress ROS and sphingolipid accumulation during Pst infection. [ABSTRACT FROM AUTHOR]