ABSTRACT
Cultivating high-yield wheat under limited water resources is crucial for sustainable agriculture in semiarid regions. Amid water scarcity, plants activate drought response signaling, yet the delicate balance between drought tolerance and development remains unclear. Through genome-wide association studies and transcriptome profiling, we identified a wheat atypical basic helix-loop-helix (bHLH) transcription factor (TF), TabHLH27-A1, as a promising quantitative trait locus candidate for both relative root dry weight and spikelet number per spike in wheat. TabHLH27-A1/B1/D1 knock-out reduced wheat drought tolerance, yield, and water use efficiency (WUE). TabHLH27-A1 exhibited rapid induction with polyethylene glycol (PEG) treatment, gradually declining over days. It activated stress response genes such as TaCBL8-B1 and TaCPI2-A1 while inhibiting root growth genes like TaSH15-B1 and TaWRKY70-B1 under short-term PEG stimulus. The distinct transcriptional regulation of TabHLH27-A1 involved diverse interacting factors such as TaABI3-D1 and TabZIP62-D1. Natural variations of TabHLH27-A1 influence its transcriptional responses to drought stress, with TabHLH27-A1Hap-II associated with stronger drought tolerance, larger root system, more spikelets, and higher WUE in wheat. Significantly, the excellent TabHLH27-A1Hap-II was selected during the breeding process in China, and introgression of TabHLH27-A1Hap-II allele improved drought tolerance and grain yield, especially under water-limited conditions. Our study highlights TabHLH27-A1's role in balancing root growth and drought tolerance, providing a genetic manipulation locus for enhancing WUE in wheat.
Subject(s)
Droughts , Gene Expression Regulation, Plant , Plant Proteins , Plant Roots , Triticum , Water , Triticum/genetics , Triticum/growth & development , Triticum/physiology , Triticum/metabolism , Plant Roots/growth & development , Plant Roots/genetics , Plant Roots/metabolism , Plant Proteins/genetics , Plant Proteins/metabolism , Water/metabolism , Quantitative Trait Loci/genetics , Basic Helix-Loop-Helix Transcription Factors/genetics , Basic Helix-Loop-Helix Transcription Factors/metabolism , Stress, Physiological/genetics , Genome-Wide Association Study , Drought ResistanceABSTRACT
Leaf senescence is an essential physiological process related to grain yield potential and nutritional quality. Green leaf duration (GLD) after anthesis directly reflects the leaf senescence process and exhibits large genotypic differences in common wheat; however, the underlying gene regulatory mechanism is still lacking. Here, we identified TaNAM-A1 as the causal gene of the major loci qGLD-6A for GLD during grain filling by map-based cloning. Transgenic assays and TILLING mutant analyses demonstrated that TaNAM-A1 played a critical role in regulating leaf senescence, and also affected spike length and grain size. Furthermore, the functional divergences among the three haplotypes of TaNAM-A1 were systematically evaluated. Wheat varieties with TaNAM-A1d (containing two mutations in the coding DNA sequence of TaNAM-A1) exhibited a longer GLD and superior yield-related traits compared to those with the wild type TaNAM-A1a. All three haplotypes were functional in activating the expression of genes involved in macromolecule degradation and mineral nutrient remobilization, with TaNAM-A1a showing the strongest activity and TaNAM-A1d the weakest. TaNAM-A1 also modulated the expression of the senescence-related transcription factors TaNAC-S-7A and TaNAC016-3A. TaNAC016-3A enhanced the transcriptional activation ability of TaNAM-A1a by protein-protein interaction, thereby promoting the senescence process. Our study offers new insights into the fine-tuning of the leaf functional period and grain yield formation for wheat breeding under various geographical climatic conditions.
Subject(s)
Edible Grain , Gene Expression Regulation, Plant , Haplotypes , Plant Leaves , Plant Proteins , Triticum , Triticum/genetics , Triticum/physiology , Triticum/growth & development , Triticum/metabolism , Plant Leaves/genetics , Plant Leaves/metabolism , Plant Leaves/physiology , Plant Proteins/metabolism , Plant Proteins/genetics , Haplotypes/genetics , Edible Grain/genetics , Edible Grain/growth & development , Plant Senescence/genetics , Genes, Plant , Genetic Variation , PhenotypeABSTRACT
Increasing the tolerance of crops to water deficit is crucial for the improvement of crop production in water-restricted regions. Here, a wheat peroxidase gene (TaPrx109-B1) belonging to the class III peroxidase gene family was identified and its function in water deficit tolerance was revealed. We demonstrated that overexpression of TaPrx109-B1 reduced leaf H2O2 level and stomatal density, increased leaf relative water content, water use efficiency, and tolerance to water deficit. The expression of TaEPF1 and TaEPF2, two key negative regulators of stomatal development, were significantly upregulated in TaPrx109-B1 overexpression lines. Furthermore, exogenous H2O2 downregulated the expression of TaEPF1 and TaEPF2 and increased stomatal density, while exogenous application of diphenyleneiodonium chloride, a potent NADPH oxidase inhibitor that repressed the synthesis of H2O2, upregulated the expression of TaEPF1 and TaEPF2, decreased stomatal density, and enhanced wheat tolerance to water deficit. These findings suggest that TaPrx109-B1 influences leaf stomatal density by modulation of H2O2 level and the expression of TaEPF1 and TaEPF2. The results of the field trial showed that overexpressing TaPrx109-B1 increased grain number per spike, which reduced the yield loss caused by water deficiency. Therefore, TaPrx109-B1 has great potential in breeding wheat varieties with improved water deficit tolerance.
Subject(s)
Hydrogen Peroxide , Plant Proteins , Plant Stomata , Plants, Genetically Modified , Triticum , Triticum/genetics , Triticum/physiology , Plant Stomata/physiology , Plant Stomata/genetics , Plant Proteins/genetics , Plant Proteins/metabolism , Hydrogen Peroxide/metabolism , Water/metabolism , Gene Expression Regulation, Plant , Droughts , Peroxidase/metabolism , Peroxidase/genetics , Plant Leaves/physiology , Plant Leaves/genetics , DehydrationABSTRACT
Nitrate is the main source of nitrogen (N) available to plants and also is a signal that triggers complex regulation of transcriptional networks to modulate a wide variety of physiological and developmental responses in plants. How plants adapt to soil nitrate fluctuations is a complex process involving a fine-tuned response to nitrate provision and N starvation, the molecular mechanisms of which remain largely uncharted. Here, we report that the wheat transcription factor TaLBD41 interacts with the nitrate-inducible transcription factor TaNAC2 and is repressed by nitrate provision. Electrophoretic mobility shift assay and dual-luciferase system show that the TaLBD41-NAC2 interaction confers homeostatic coordination of nitrate uptake, reduction, and assimilation by competitively binding to TaNRT2.1, TaNR1.2, and TaNADH-GOGAT. Knockdown of TaLBD41 expression enhances N uptake and assimilation, increases spike number, grain yield, and nitrogen harvest index under different N supply conditions. We also identified an elite haplotype of TaLBD41-2B associated with increased spike number and grain yield. Our study uncovers a novel mechanism underlying the interaction between two transcription factors in mediating wheat adaptation to nitrate availability by antagonistically regulating nitrate uptake and assimilation, providing a potential target for designing varieties with efficient N use in wheat (Triticum aestivum).
Subject(s)
Nitrates , Nitrogen , Nitrates/metabolism , Nitrogen/metabolism , Biological Transport , Edible Grain/metabolism , Transcription Factors/genetics , Transcription Factors/metabolismABSTRACT
Objective·To evaluate the effects of anterior maxillary segmental distraction osteogenesis(AMSDO)in treating sagittal maxillary hypoplasia in cleft lip and palate(CLP)patients and to report a 3D-printed surgical guide to facilitate the osteotomy.Methods·Twelve patients with CLP who underwent AMSDO were included in this study.Virtual osteotomy was performed in a 3-dimensional model and the osteotomy line were fabricated into a tooth-borne surgical guide by using 3D-printing technique.Lateral cephalograms taken before surgery(T0),at the end of consolidation(T1)and six months after consolidation(T2)were used to evaluate the effects of AMSDO.The accuracy of the osteotomy guide was measured by superimposing the postoperative CT data to virtual planning.Results·All the patients went through surgery without serious complications.SNA and overjet changed significantly both from T0 to T1 and from T0 to T2.ANB,facial convexity,and palatal length changed without significance from T0 to T1 and from T0 to T2.SNB remained stable.All the variables remained relatively stable from T1 to T2.The anteroposterior linear root-mean-square deviation(RMSD)between planning and actual results was 0.90 mm,while the angular RMSD in the sagittal plane was 5.07°.Conclusion·AMSDO is an effective treatment for maxillary hypoplasia secondary to CLP.The accuracy of this 3D-printed osteotomy guide is clinically acceptable,and this can simplify the surgery with fewer complications.
ABSTRACT
A biosynthetic gene cluster for the bioactive fungal sesterterpenoids variecolin ( 1) and variecolactone ( 2) was identified in Aspergillus aculeatus ATCC 16872. Heterologous production of 1 and 2 was achieved in Aspergillus oryzae by expressing the sesterterpene synthase VrcA and the cytochrome P450 VrcB. Intriguingly, the replacement of VrcB with homologous P450s from other fungal terpenoid pathways yielded three new variecolin analogues ( 5- 7). Analysis of the compounds' anticancer activity in vitro and in vivo revealed that although 5 and 1 had comparable activities, 5 was associated with significantly reduced toxic side effects in cancer-bearing mice, indicating its potentially broader therapeutic window. Our study describes the first tests of variecolin and its analogues in animals and demonstrates the utility of synthetic biology for creating molecules with improved biological activities.
ABSTRACT
ABSTRACT: Soil salinity limits agricultural production and is a major obstacle for increasing crop yield. Common wheat is one of the most important crops with allohexaploid characteristic and a highly complex genome. QTL mapping is a useful way to identify genes for quantitative traits such as salinity tolerance in hexaploid wheat. In the present study, a hydroponic trial was carried out to identify quantitative trait loci (QTLs) associated with salinity tolerance of wheat under 150mM NaCl concentration using a recombinant inbred line population (Xiaoyan 54×Jing 411). Values of wheat seedling traits including maximum root length (MRL), root dry weight (RDW), shoot dry weight (SDW), total dry weight (TDW) and the ratio of TDW of wheat plants between salt stress and control (TDWR) were evaluated or calculated. A total of 19QTLs for five traits were detected through composite interval mapping method by using QTL Cartographer version 2.5 under normal and salt stress conditions. These QTLs distributed on 12 chromosomes explained the percentage of phenotypic variation by individual QTL varying from 7.9% to 19.0%. Among them, 11 and six QTLs were detected under normal and salt stress conditions, respectively and two QTLs were detected for TDWR. Some salt tolerance related loci may be pleiotropic. Chromosome 1A, 3A and 7A may harbor crucial candidate genes associated with wheat salt tolerance. Our results would be helpful for the marker assisted selection to breed wheat varieties with improved salt tolerance.
RESUMO: A salinidade do solo limita a produção agrícola. O trigo mole é uma das culturas mais importantes com característica allohexaploid e genoma altamente complexo. O mapeamento QTL é uma maneira muito útil de identificar genes para traços quantitativos, como a tolerância à salinidade em trigo hexaplóide. No presente estudo realizou-se um ensaio hidropónico para identificar locos de traços quantitativos (QTLs) associados à tolerância à salinidade do trigo sob concentração de NaCl 150 mM, usando uma população de linhagem consanguíneo recombinante (Xiaoyan 54 × Jing 411). Os valores dos traços de mudas de trigo, incluindo comprimento máximo da raiz (MRL), peso seco da raiz (RDW), ponha o peso seco (SDW), peso seco total (TDW) e a proporção das plantas de trigo TDW entre o estresse salgado e o controle (TDWR), foram avaliados ou calculados. Um total de 19QTLs para cinco traços foram detectados através do método de mapeamento de intervalo composto usando a versão 2.5 do cartógrafo QTL sob condições normais e de estresse salino. Estes QTLs distribuídos em 12 cromossomos explicaram a porcentagem de variação fenotípica por QTL individual variando de 7,9% a 19,0%. Entre eles, foram detectados 11 e 6 QTLs em condições de estresse normal e sal, respectivamente, e dois QTLs foram detectados para TDWR. Cromossoma 1A, 3A e 7A podem conter genes que são candidatos cruciais associados à tolerância ao sal de trigo. Nossos resultados seriam úteis para a seleção assistida por marcadores para produzir variedades de trigo com tolerância salina melhorada.
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the duration of speech therapy of patients with or without velopharyngeal insufficency after palatoplasty.</p><p><b>METHODS</b>One hundred and one cleft-palate patients with velopharyngeal incompetence (VPI) and eighty-seven without VPI were selected in the study. The treatment times of the patients who completed the speech therapy were counted and analyzed.</p><p><b>RESULTS</b>The mean treatment frequency in VPI group was 17 times, and in the group without VPI this number was 13 (P < 0.05). In 39 VPI patients with signs of velocardiofaical syndrome, the mean treatment frequency was 19 times, and the mean treatment frequency of the other 62 patents with nonsyndromic VPI was 15 times (P < 0.05).</p><p><b>CONCLUSIONS</b>The duration of speech therapy in VPI patients is longger than that in patients without VPI after palatoplasy, but individualized treatment is necessary.</p>