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Pre-harvest sprouting (PHS) induced by the absence of seed dormancy causes a severe reduction in crop yield and flour quality. In this study, we isolated and characterized TaABI4, an ABA-responsive transcription factor that participates in regulating seed germination in wheat. Sequence analysis revealed that TaABI4 has three homologues, located on chromosomes 1A/1B/1D. TaABI4 contains a conserved AP2 domain, and AP2-associated, LRP and potential PEST motifs. Putative cis-acting regulatory elements (CE1-like box, W-box, ABRE elements and RY elements) were identified in the TaABI4 promoter region that showed high conservation in 17 wheat cultivars and wheat-related species. Expression profiling of TaABI4 indicated that it is a seed-specific gene accumulating during the middle stages of seed development. Transcript accumulation of TaABI4 in wheat cultivar Chuanmai 32 (CM32, PHS susceptible) was 5.07-fold and 1.39-fold higher than that in synthetic hexaploidy wheat SHW-L1 (PHS resistant) at 15 and 20 DPA, respectively. Six expression quantitative trait loci (eQTL) of TaABI4 on chromosomes 2A, 2D, 3B and 4A were characterized based on the accumulated transcripts of TaABI4 in SHW-L1 and CM32-derived recombinant inbred lines. These QTLs explained 10.7 to 46.1% of the trait variation with 4.53–10.59 of LOD scores, which contain genes that may affect the expression of TaABI4.

MYB transcription factors (TFs) represents one of the largest TF families in plants. In this study, we performed genome-wide MYB-domain screening and identified a total of 997 MYBs in wheat (Triticum aestivum), among which 445 were 2-domain MYBs (R2R3-MYBs) that were clustered into 15 subgroups with varied conservation profiles. Homologous genes were highly conserved across the three subgenomes, with minor variations contributed by segmental duplications. Tandem and proximal gene duplications have contributed significantly to the expansion of the wheat Myb gene family. Furthermore, comprehensive transcriptome profiling of R2R3-Myb genes in 61 different tissue and time point samples revealed a clear pattern of temporal and spatial variations within six expression groups. The comprehensive genomic and transcriptional analyses provided valuable insights into the evolution and biological functions of R2R3-Myb genes in wheat. They would serve as a useful guide to further investigate the potential agronomic traits controlled by this large TF family.

Pre-harvest sprouting (PHS) induced by the decline of seed dormancy causes a severe reduction in crop yield and flour quality. In this study, we isolated and characterizedTaABI4,an ABA-responsive transcription factor that participates in regulating seed germination in wheat. Sequence analysis revealed thatTaABI4has three homologues, located on chromosomes 1A/1B/1D. TaABI4 contains a conserved AP2 domain, and AP2-associated, LRP, and potential PEST motifs. Putativecis-acting regulatory elements (CE1-like box, W-box, ABRE elements, and RY-elements) were identified in theTaABI4promoter region that showed high conservation in 17 wheat cultivars and wheat-related species. Expression profiling ofTaABI4indicated that it is a seed-specific gene accumulating during the middle stages of seed development. Transcript accumulation ofTaABI4in wheat cultivar Chuanmai 32 (CM32, PHS susceptible) was 5.07-fold and 1.39-fold higher than that in synthetic hexaploidy wheat SHW-L1 (PHS resistant) at 15DPA and 20DPA, respectively. Six expression quantitative trait loci (eQTL) ofTaABI4on chromosome 2A, 2D, 3B, and 4A were characterized based on the accumulated transcripts ofTaABI4in SHW-L1 and CM32 derived recombinant inbred lines. These QTLs explained from 10.7% to 46.1% of the trait variation with 4.53~10.59 of LOD scores, which contain genes that may affect the expression ofTaABI4.

Predicted climate change is widely cited to significantly reduce yields of the major cereal crop species in a period where demand is rapidly rising due to a growing global population. This requires exhaustive research to develop genetic resources in order to address the expected production deficiencies which will largely be driven by abiotic stress. Modification of multiple genes is an approach that can address the predicted challenges; however, it is time-consuming and costly to modify multiple genes simultaneously. Transcription factors represent a group of proteins regulating multiple genes simultaneously and are therefore promising targets to concurrently improve multiple traits concurrently, such as abiotic stress tolerance and grain size (a contributor to yield). Many studies have identified the complex role that transcription factors of multiple families have contributed toward abiotic stress tolerance or grain size, although research addressing both simultaneously is in its infancy despite its potential significance for cereal crop improvement. Here we discuss the potential role that transcription factors may contribute toward improving cereal crop productivity under adverse environmental conditions and offer research objectives that need to be addressed before the modification of transcription factors becomes routinely used to positively manipulate multiple target traits.

International audience; Ten years on from the 2008 global financial crisis, this article sets in dialogue two French treatments – by the novelist Mathieu Larnaudie and the philosopher Bernard Stiegler – of footage of the 2008 testimony of Alan Greenspan, former chairman of the US Federal Reserve, before the United States House of Representatives Committee on Oversight and Government Reform. The article introduces and compares the concepts of ‘effondrement’ and ‘prolétarisation’ developed by the two writers in relation to the Greenspan hearing, and analyses how both understand the question of ideology as it emerges in the hearing. Informed by interviews conducted by the author with Larnaudie and Stiegler, the piece concludes by discussing the notion common to both writers that Greenspan is a ‘saint’ of the crisis.

Key message A major grain length QTL on chromosome 2H was fine mapped to a 140.9 Kb region containing three genes. Abstract Increasing yield is an important target for barley breeding programs. One approach to increase yield is by enhancing individual grain weights through the regulation of grain size. Fine mapping major grain size-related quantitative trait loci is necessary for future marker-assisted selection strategies, yet studies of this nature are limited in barley. In the present study, we utilised a doubled haploid population derived from two Australian malt barley varieties, Vlamingh and Buloke, coupled with extensive genotypic and phenotypic data from three independent environments. A major grain length locus identified on chromosome 2H designated qGL2H was fine mapped to a 140.9 Kb interval. qGL2H was able to account for 25.4% of the phenotypic variation for grain length and 10.2% for grain yield. Underlying qGL2H were three high-confidence predicted genes. One of these genes encodes a MYB transcription factor and represents a promising candidate for further genetic research.

The gene HvDEP1, on barley (Hordeum vulgare L.) chromosome 5H, encodes a γ-subunit of the heterotrimeric G-protein complex and was previously determined to be a candidate gene underlying a major quantitative trait locus for grain length. In the present study, we identified a 9 bp indel (insertion–deletion mutation) at position –84 bp from the start codon within a reported upstream open reading frame located in the 5′ UTR (untranslated region) and developed a diagnostic molecular marker. We also identified a 13 bp indel (–514 bp) in linkage disequilibrium that bridges an important regulatory motif. Using a doubled-haploid population and a barley diversity panel, we were able to show that the effects of these indels were environmentally stable and consistently delineated phenotypic groups based on grain length and 1000-grain weight. Genotypes represented by deletions at these two positions relative to the reference cv. Morex had consistently shorter grains, by 3.69–3.96%, and lower 1000-grain weight, by 2.38–4.21%, in a doubled-haploid population studied. Additionally, a diversity panel was tested but consistent differences were observed only for grain length, reinforcing literature indicating the importance of this gene for grain-length regulation. The frequency of the longer and heavier grained reference allele was higher in modern cultivars, suggesting that indirect selection for longer grain may have occurred through direct selection for grain yield via grain-weight improvement. These results indicate that grain length and 1000-grain weight in barley can be manipulated by targeting variation in gene promoters through marker-assisted selection.