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This article discusses the role of the transcription factor TaMYB72 in promoting heading and enhancing grain yield traits in wheat. The researchers used CRISPR/Cas9-based gene editing to create knockout mutants of TaMYB72 and found that these mutants displayed later heading dates and increased grain yield traits compared to the wild-type plants. The study also revealed that TaMYB72 directly activates the expression of TaFT, a gene involved in flowering and spikelet development, to regulate the height and yield traits of wheat. These findings provide valuable insights into the genetic basis of grain yield traits and heading date in wheat, and suggest TaMYB72 as a potential target gene for increasing grain yield in breeding programs. [Extracted from the article]

Summary: Plant height and grain size are two important agronomic traits that are closely related to crop yield. Numerous dwarf and grain‐shape mutants have been studied to identify genes that can be used to increase crop yield and improve breeding programs.In this study, we characterized a dominant mutant, dwarf and round grain 1 (drg1‐D), in bread wheat (Triticum aestivum L.). drg1‐D plants exhibit multiple phenotypic changes, including dwarfism, round grains, and insensitivity to brassinosteroids (BR). Cell structure observation in drg1‐D mutant plants showed that the reduced organ size is due to irregular cell shape.Using map‐based cloning and verification in transgenic plants, we found that a Glu209Lys substitution in the DRG1 protein is responsible for the irregular cell size and arrangement in the drg1‐D mutant. DRG1/TaACT7 encodes an actin family protein that is essential for polymerization stability and microfilament (MF) formation. In addition, the BR response and vesicular transport were altered by the abnormal actin cytoskeleton in drg1‐D mutant plants.Our study demonstrates that DRG1/TaACT7 plays an important role in wheat cell shape determination by modulating actin organization and intracellular material transport, which could in the longer term provide tools to better understand the polymerization of actin and its assembly into filaments and arrays. [ABSTRACT FROM AUTHOR]

Wheat (Triticum aestivum L.) is a staple food crop that provides 20% of total human calorie consumption. Gene duplication has been considered to play an important role in evolution by providing new genetic resources. However, the evolutionary fates and biological functions of the duplicated genes in wheat remain to be elucidated. In this study, the resulting data showed that the duplicated genes evolved faster with shorter gene lengths, higher codon usage bias, lower expression levels, and higher tissue specificity when compared to non-duplicated genes. Our analysis further revealed functions of duplicated genes in various biological processes with significant enrichment to environmental stresses. In addition, duplicated genes derived from dispersed, proximal, tandem, transposed, and whole-genome duplication differed in abundance, evolutionary rate, gene compactness, expression pattern, and genetic diversity. Tandem and proximal duplicates experienced stronger selective pressure and showed a more compact gene structure with diverse expression profiles than other duplication modes. Moreover, genes derived from different duplication modes showed an asymmetrical evolutionary pattern for wheat A, B, and D subgenomes. Several candidate duplication hotspots associated with wheat domestication or polyploidization were characterized as potential targets for wheat molecular breeding. Our comprehensive analysis revealed the evolutionary trajectory of duplicated genes and laid the foundation for future functional studies on wheat. [ABSTRACT FROM AUTHOR]

We tested whether VRN1 is a substrate of GSK3 phosphorylation by performing I in vitro i VRN1 phosphorylation assays using equivalent amounts of GSK3 or gsk3 proteins. To further test whether GSK3 regulates VRN1 protein abundance, we performed a cell-free protein degradation assay to monitor the contents of GST-VRN1 in the absence or presence of the 26S proteasome inhibitor MG132. GLYCOGEN SYNTHASE KINASE 3 physically interacts with VRN1 and regulates its accumulation to mediate flowering in wheat. [Extracted from the article]

Wheat is one of the world's major staple food crops, and breeding for improvement of grain yield is a priority under the scenarios of climate change and population growth. WRKY transcription factors are multifaceted regulators in plant growth, development, and responses to environmental stimuli. In this study, we identify the WRKY gene TaGSNE (Grain Size and Number Enhancer) in common wheat, and find that it has relatively high expression in leaves and roots, and is induced by multiple abiotic stresses. Eleven single-nucleotide polymorphisms were identified in TaGSNE , forming two haplotypes in multiple germplasm collections, named as TaGSNE-Hap-1 and TaGSNE-Hap-2. In a range of different environments, TaGSNE-Hap-2 was significantly associated with increases in thousand-grain weight (TGW; 3.0%) and spikelet number per spike (4.1%), as well as with deeper roots (10.1%) and increased root dry weight (8.3%) at the mid-grain-filling stage, and these were confirmed in backcross introgression populations. Furthermore, transgenic rice lines overexpressing TaGSNE had larger panicles, more grains, increased grain size, and increased grain yield relative to the wild-type control. Analysis of geographic and temporal distributions revealed that TaGSNE-Hap-2 is positively selected in China and Pakistan, and TaGSNE-Hap-1 in Europe. Our findings demonstrate that TaGSNE overcomes the trade-off between TGW/grain size and grain number, leading us to conclude that these elite haplotypes and their functional markers could be utilized in marker-assisted selection for breeding high-yielding varieties. [ABSTRACT FROM AUTHOR]

Ms2 is an important dominant male-sterile gene in wheat, but the biochemical function of Ms2 and the mechanism by which it causes male sterility remain elusive. Here, we report the molecular basis underlying Ms2-induced male sterility in wheat. We found that activated Ms2 specifically reduces the reactive oxygen species (ROS) signals in anthers and thereby induces termination of wheat anther development at an early stage. Furthermore, our results indicate that Ms2 is localized in mitochondria, where it physically interacts with a wheat homolog of ROS modulator 1 (TaRomo1). Romo1 positively regulates the ROS levels in humans but has never been studied in plants. We found that single amino acid substitutions in the Ms2 protein that rescue the ms2 male-sterile phenotype abolish the interaction between Ms2 and TaRomo1. Significantly, Ms2 promotes the transition of TaRomo1 proteins from active monomers to inactive oligomers. Taken together, our findings unravel the molecular basis of Ms2-induced male sterility and reveal a regulatory mechanism in which ROS act as essential signals guiding the anther development program in wheat. The orphan gene Ms2 is an important dominant male-sterile gene in wheat , but the molecular basis by which it confers male sterility is completely unknown. This study demonstrates that Ms2 directly interacts with mitochondrial ROS modulator 1 in wheat (TaRomo1) and affects the oligomerization state of TaRomo1 to regulate ROS levels in anthers. These findings highlight an essential role of ROS in promoting anther development in wheat. [ABSTRACT FROM AUTHOR]

Summary: Tillering is an important parameter of plant architecture in cereal crops. In this study, we identified the PHYTOCHROME‐INTERACTING FACTOR‐LIKE (PIL) family transcription factors as new repressors of tillering in cereal crops.Using biochemical and genetic approaches, we explore the roles of TaPIL1 in regulating wheat plant architecture. We found that the PIL protein TaPIL1 controls tiller number in wheat.Overexpression of TaPIL1 reduces wheat tiller number; additionally, overexpression of TaPIL1‐SUPERMAN repression domain increases wheat tiller number. Furthermore, we show that TaPIL1 activates the transcriptional expression of wheat TEOSINTE BRANCHED1 (TaTB1); moreover, TaPIL1 physically interacts with wheat SQUAMOSA PROMOTER BINDING PROTEIN‐LIKE (TaSPL)3/17, which are activators of TaTB1 transcription. In rice, overexpression and loss‐of‐function mutations of OsPIL11 reduce or increase tiller number by regulating the expression of OsTB1. In Arabidopsis, we demonstrate that PHYTOCHROME‐INTERACTING FACTOR 4 interacts with SPL9 to inhibit shoot branching.This study reveals that PIL family transcription factors directly interact with SPLs and play an important role in repressing tillering/branching in plants. [ABSTRACT FROM AUTHOR]

Summary: The domestication gene Q is largely responsible for the widespread cultivation of wheat because it confers multiple domestication traits. However, the underlying molecular mechanisms of how Q regulates these domestication traits remain unclear.In this study, we identify a Q‐interacting protein TaLAX1, a basic helix–loop–helix transcription factor, through yeast two‐hybrid assays. Using biochemical and genetic approaches, we explore the roles of TaLAX1 in regulating wheat domestication traits.Overexpression of TaLAX1 produces phenotypes, reminiscent of the q allele; loss‐of‐function Talax1 mutations confer compact spikes, largely similar to the Q‐overexpression wheat lines. The two transcription factors TaLAX1 and Q disturb each other's activity to antagonistically regulate the expression of the lignin biosynthesis‐related gene TaKNAT7‐4D. More interestingly, a natural variation (InDel, +/− TATA), which occurs in the promoter of TaLAX1, is associated with the promoter activity difference between the D subgenome of bread wheat and its ancestor Aegilops tauschii accession T093.This study reveals that the transcription factor TaLAX1 physically interacts with Q to antagonistically regulate wheat domestication traits and a natural variation (InDel, +/− TATA) is associated with the diversification of TaLAX1 promoter activity. [ABSTRACT FROM AUTHOR]

The discovery of functional genes underlying agronomic traits is of great importance for wheat improvement. Here we designed a new wheat exome capture probe panel based on IWGSC RefSeq v1.0 genome sequence information and developed an effective algorithm, varBScore, that can sufficiently reduce the background noise in gene mapping and identification. An effective method, termed b ulked s egregant e xome capture seq uencing (BSE-Seq) for identifying causal mutations or candidate genes was established by combining the use of a newly designed wheat exome capture panel, sequencing of bulked segregant pools from segregating populations, and the robust algorithm varBScore. We evaluated the effectiveness of varBScore on SNP calling using the published dataset for mapping and cloning the yellow rust resistance gene Yr7 in wheat. Furthermore, using BSE-Seq, we rapidly identified a wheat yellow leaf mutant gene, ygl1 , in an ethyl methanesulfonate (EMS) mutant population and found that a single mutation of G to A at 921 position in the wild type YGL1 gene encoding magnesium-chelatase subunit chlI caused the leaf yellowing phenotype. We further showed that mutation of YGL1 through CRISPR/Cas9 gene editing led to a yellow phenotype on the leaves of transgenic wheat, indicating that ygl1 is the correct causal gene responsible for the mutant phenotype. In summary, our approach is highly efficient for discovering causal mutations and gene cloning in wheat. [ABSTRACT FROM AUTHOR]

The heading date is critical in determining the adaptability of plants to specific natural environments. Molecular characterization of the wheat genes that regulate heading not only enhances our understanding of the mechanisms underlying wheat heading regulation but also benefits wheat breeding programs by improving heading phenotypes. In this study, we characterized a late heading date mutant, m605, obtained by ethyl methanesulfonate (EMS) mutation. Compared with its wild-type parent, YZ4110, m605 was at least 7 days late in heading when sown in autumn. This late heading trait was controlled by a single recessive gene named TaHdm605. Genetic mapping located the TaHdm605 locus between the molecular markers cfd152 and barc42 on chromosome 3DL using publicly available markers and then further mapped this locus to a 1.86 Mb physical genomic region containing 26 predicted genes. This fine genetic and physical mapping will be helpful for the future map-based cloning of TaHdm605 and for breeders seeking to engineer changes in the wheat heading date trait. [ABSTRACT FROM AUTHOR]

Leaf senescence is an important agronomic trait that affects both crop yield and quality. In this study, we characterized a premature leaf senescence mutant of wheat (Triticum aestivum L.) obtained by ethylmethane sulfonate (EMS) mutagenesis, named m68. Genetic analysis showed that the leaf senescence phenotype of m68 is controlled by a single recessive nuclear gene. We compared the transcriptome of wheat leaves between the wild type (WT) and the m68 mutant at four time points. Differentially expressed gene (DEG) analysis revealed many genes that were closely related to senescence genes. Gene Ontology (GO) enrichment analysis suggested that transcription factors and protein transport genes might function in the beginning of leaf senescence, while genes that were associated with chlorophyll and carbon metabolism might function in the later stage. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that the genes that are involved in plant hormone signal transduction were significantly enriched. Through expression pattern clustering of DEGs, we identified 1012 genes that were induced during senescence, and we found that the WRKY family and zinc finger transcription factors might be more important than other transcription factors in the early stage of leaf senescence. These results will not only support further gene cloning and functional analysis of m68, but also facilitate the study of leaf senescence in wheat. [ABSTRACT FROM AUTHOR]

Correction to: I Nature Communications i https://doi.org/10.1038/s41467-023-36271-z, published online 14 February 2023 The original version of this Article contained an error in Fig. This has been corrected in both the PDF and HTML versions of the Article. [Extracted from the article]

Leaf rolling is an important agronomic trait in crop breeding. Moderate leaf rolling maintains the erectness of leaves and minimizes shadowing between leaves, leading to improved photosynthetic efficiency. Although some genes controlling leaf rolling have been isolated from rice and other plant species, few studies have examined leaf rolling in wheat. In the present study, the leaf rolling regulator gene, TaMYB18 , was identified in a large-scale transgene project involving the transformation of 1455 wheat transcription factor genes into rice. Three homologous sequences of TaMYB18 were isolated from hexaploid wheat and localized to chromosomes 5A, 5B and 5D, respectively. TaMYB18, an R2R3-MYB transcription factor, localized to the nucleus. TaMYB18 overexpression induced leaf rolling in transgenic rice. Additionally, the three members of TaMYB18 exhibited functional redundancy in rice. Furthermore, the function of TaMYB18 in regulating leaf rolling in rice was a dose-dependent. Taken together, these results indicate that TaMYB18 may play an important role in the regulation of leaf development. [ABSTRACT FROM AUTHOR]

SUMMARY Through large-scale transformation analyses, TaMYB72 was identified as a flowering time regulator in wheat. TaMYB72 is a MYB family transcription factor localized to the nucleus. Three TaMYB72 homologs, TaMYB72-A, TaMYB72-B and TaMYB72-D, cloned from hexaploid wheat were mapped to the short arm of the group 6 chromosomes. Under the long-day conditions, over-expression of the TaMYB72 in rice shortened the flowering time by approximately 12 d. Expression analyses suggest that TaMYB72 may function through up-regulation of florigen genes Hd3a and RFT1. [ABSTRACT FROM AUTHOR]

Although bHLH transcription factors play important roles regulating plant development and abiotic stress response and tolerance, few functional studies have been performed in wheat. In this study, we isolated and characterized a bHLH gene, TabHLH39 , from wheat. The TabHLH39 gene is located on wheat chromosome 5DL, and the protein localized to the nucleus and activated transcription. TabHLH39 showed variable expression in roots, stems, leaves, glumes, pistils and stamens and was induced by polyethylene glycol, salt and cold treatments. Further analysis revealed that TabHLH39 overexpression in Arabidopsis significantly enhanced tolerance to drought, salt and freezing stress during the seedling stage, which was also demonstrated by enhanced abiotic stress-response gene expression and changes to several physiological indices. Therefore, TabHLH39 has potential in transgenic breeding applications to improve abiotic stress tolerance in crops. [ABSTRACT FROM AUTHOR]

MYB-type proteins have been shown to participate in multiple stress responses. In the present study, we identified a gene in wheat induced by multiple abiotic stresses, TaMYB19, which encodes a R2R3-type MYB protein. Three highly homologous sequences of TaMYB19 were isolated from hexaploid wheat. Using the nulli-tetrasomic (NT) lines of Chinese Spring wheat, the three sequences were localized to chromosomes 1A, 1B and 1D and designated as TaMYB19-A, TaMYB19-B and TaMYB19-D, respectively. The expression patterns of these three genes were similar under different stress conditions. The TaMYB19-B sequence was selected for further analysis. The TaMYB19-B protein localized to the nucleus. A detailed characterization of Arabidopsis transgenic plants overexpressing the TaMYB19-B gene revealed that the TaMYB19-B protein could improve tolerance to multiple stresses during the seedling stage. We also found that the overexpression of TaMYB19-B resulted in changes in several physiological indices and altered the expression levels of a number of abiotic stress-related genes, allowing the plants to overcome adverse conditions. These results indicate that the TaMYB19 protein plays an important role in plant stress tolerance and that modification of the expression of this protein may improve abiotic stress tolerance in crop plants. [ABSTRACT FROM AUTHOR]

Rht-D1c ( Rht10) carried by Chinese wheat ( Triticum aestivum) line Aibian 1 is an allele at the Rht-D1 locus. Among the Rht-1 alleles, little is known about Rht-D1c although it determines an extreme dwarf phenotype in wheat., Here, we cloned and functionally characterized Rht-D1c using a combination of Southern blotting, target region sequencing, gene expression analysis and transgenic experiments., We found that the Rht-D1c allele was generated through a tandem segmental duplication (TSD) of a > 1 Mb region, resulting in two copies of the Rht-D1b. Two copies of Rht-D1b in the TSD were three-fold more effective in reducing plant height than a single copy, and transformation with a segment containing the tandemly duplicated copy of Rht-D1b resulted in the same level of reduction of plant height as the original copy in Aibian 1., Our results suggest that changes in gene copy number are one of the important sources of genetic diversity and some of these changes could be directly associated with important traits in crops. [ABSTRACT FROM AUTHOR]

Abstract: The MYB proteins play central roles in the stress response in plants. Our previous works identified a cold stress-related gene, TaMYB56, which encodes a MYB protein in wheat. In this study, we isolated the sequences of TaMYB56 genes, and mapped them to the wheat chromosomes 3B and 3D. The expression levels of TaMYB56-B and TaMYB56-D were strongly induced by cold stress, but slightly induced by salt stress in wheat. The detailed characterization of the Arabidopsis transgenic plants that overexpress TaMYB56-B revealed that TaMYB56-B is possibly involved in the responses of plant to freezing and salt stresses. The expression of some cold stress-responsive genes, such as DREB1A/CBF3 and COR15a, were found to be elevated in the TaMYB56-B-overexpressing Arabidopsis plants compared to wild-type. These results indicate that TaMYB56-B may act as a regulator in plant stress response. [Copyright &y& Elsevier]

Previously we have found that TabZIP60 from the ABF/AREB (ABRE-binding factor/ABA-responsive element-binding protein) subfamily of bZIP transcription factor (TF) was involved in salt stress response. However, the regulatory mechanism of TabZIP60 is unknown. In the present study, we identified two calcium-dependent protein kinase (CDPK) genes, TaCDPK5/TaCDPK9–1 , which were clustered into group Ⅰ and were induced by salt, abscisic acid (ABA), and polyethylene glycol (PEG) treatments. RT-qPCR results showed that the expression level of salt-induced TabZIP60 was drastically inhibited by Ca2+ channel blocker LaCl 3. TaCDPK5/TaCDPK9–1 were involved in interaction with TabZIP60 protein in vivo and in vitro. And TaCDPK5/TaCDPK9–1 could autophosphorylate and phosphorylate TabZIP60 protein in a Ca2+-dependent way. Mutational analysis indicated that Serine-110 of TabZIP60 was essential for TaCDPK5/TaCDPK9–1-TabZIP60 interaction and was the phosphorylation site of TaCDPK5/TaCDPK9–1 kinases. Yeast two-hybrid assay results showed the interactions between TaCDPK5/TaCDPK9–1 and wheat protein phosphatase 2 C clade A TaPP2CA116/ TaPP2CA121 separately. These findings demonstrate that the phosphorylation status of TabZIP60 controlled by TaPP2CA116/ TaPP2CA121 and TaCDPK5/TaCDPK9–1 might play a crucial role in wheat during salt stress. • TaCDPK5 and TaCDPK9-1 are induced by abiotic stresses. Salt-induced TabZIP60 expression is inhibited by Ca2+ blocker LaCl 3. • TaPP2CA116 and TaPP2CA121 interplay with TaCDPK5 and TaCDPK9-1 respectively, which can interact with and phosphorylate TabZIP60 protein. • The Ser-110 of TabZIP60 is necessary for the TaCDPK5/TaCDPK9-1-TabZIP60 interaction and phosphorylated by TaCDPK5/TaCDPK9-1. [ABSTRACT FROM AUTHOR]