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1.
Am J Pathol ; 191(8): 1431-1441, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34294192

RESUMO

Glomeruli instance segmentation from pathologic images is a fundamental step in the automatic analysis of renal biopsies. Glomerular histologic manifestations vary widely among diseases and cases, and several special staining methods are necessary for pathologic diagnosis. A robust model is needed to segment and classify glomeruli with different staining methods and apply in cases with various glomerular pathologic changes. Herein, pathologic images from renal biopsy slides stained with three basic special staining methods were used to build the data sets. The snapshot group included 1970 glomeruli from 516 patients, and the whole-slide image group included 8665 glomeruli from 148 patients. Cascade Mask region-based convolutional neural net architecture was trained to detect, classify, and segment glomeruli into three categories: i) GN, structural normal; ii) global sclerosis; and iii) glomerular with other lesions. In the snapshot group, total glomeruli, GN, global sclerosis, and glomerular with other lesions achieved an F1 score of 0.914, 0.896, 0.681, and 0.756, respectively, which were comparable with those in the whole-slide image group (0.940, 0.839, 0.806, and 0.753, respectively). Among the three categories, GN achieved the best instance segmentation effect in both groups, as determined by average precision, average recall, F1 score, and Mask mean Intersection over Union. The present model segments and classifies multistained glomeruli with efficiency and robustness. It can be applied as the first step for more detailed glomerular histologic analysis.


Assuntos
Aprendizado Profundo , Interpretação de Imagem Assistida por Computador/métodos , Nefropatias/diagnóstico , Glomérulos Renais/patologia , Biópsia , Humanos , Nefropatias/patologia , Coloração e Rotulagem
2.
New Phytol ; 229(1): 370-387, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33411361

RESUMO

Nonphotochemical quenching (NPQ), an intricate photoprotective process, plays fundamental roles in maintaining plant fitness. The PsbS protein is essential for the rapid induction of NPQ, and acts in a dose-dependent manner in leaves. However, little information is known on the transcriptional control of PsbS in land plants. Here we demonstrated that the expression of OsPsbS1 is directly upregulated by OsbZIP72 while repressed by OsMYBS2 in rice. We identified a new cis-element GACAGGTG in japonica OsPsbS1 promoter, to which OsbZIP72 could strongly bind and activate the expression of OsPsbS1. The new cis-element CTAATC confers specific binding for OsMYBS2 in japonica OsPsbS1 promoter. OsbZIP72 can be activated by SAPK1, and acts depending on the abscisic acid (ABA) signalling pathway. GF14A protein affects the repression activity of OsMYBS2 by regulating its nucleocytoplasmic shuttling, and Ser53 is necessary for OsMYBS2 to be retained in the cytoplasm. The inducibility of OsPsbS1 transcription under high light conditions in OsbZIP72 knockout lines was greatly impaired, while the repression of OsPsbS1 transcription under a low light environment in OsMYBS2 knockout lines was significantly alleviated. These results reveal cross-talk among NPQ processes, the ABA signalling pathway and abiotic stress signalling. The elaborate mechanisms may help enhance photoprotection and improve photosynthesis in rice.


Assuntos
Oryza , Ácido Abscísico , Regulação da Expressão Gênica de Plantas , Oryza/genética , Oryza/metabolismo , Fotossíntese , Complexo de Proteína do Fotossistema II/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Estresse Fisiológico/genética
3.
J Integr Plant Biol ; 63(5): 878-888, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32886450

RESUMO

Appearance and taste are important factors in rice (Oryza sativa) grain quality. Here, we investigated the taste scores and related eating-quality traits of 533 diverse cultivars to assess the relationships between-and genetic basis of-rice taste and eating-quality. A genome-wide association study highlighted the Wx gene as the major factor underlying variation in taste and eating quality. Notably, a novel waxy (Wx) allele, Wxla , which combined two mutations from Wxb and Wxin , exhibited a unique phenotype. Reduced GBSSI activity conferred Wxla rice with both a transparent appearance and good eating quality. Haplotype analysis revealed that Wxla was derived from intragenic recombination. In fact, the recombination rate at the Wx locus was estimated to be 3.34 kb/cM, which was about 75-fold higher than the genome-wide mean, indicating that intragenic recombination is a major force driving diversity at the Wx locus. Based on our results, we propose a new network for Wx evolution, noting that new Wx alleles could easily be generated by crossing genotypes with different Wx alleles. This study thus provides insights into the evolution of the Wx locus and facilitates molecular breeding for quality in rice.

4.
Mol Plant ; 14(3): 456-469, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33307246

RESUMO

Rice grain oil is a valuable nutrient source. However, the genetic basis of oil biosynthesis in rice grains remains unclear. In this study, we performed a genome-wide association study on oil composition and oil concentration in a diverse panel of 533 cultivated rice accessions. High variation for 11 oil-related traits was observed, and the oil composition of rice grains showed differentiation among the subpopulations. We identified 46 loci that are significantly associated with grain oil concentration or composition, 16 of which were detected in three recombinant inbred line populations. Twenty-six candidate genes encoding enzymes involved in oil metabolism were identified from these 46 loci, four of which (PAL6, LIN6, MYR2, and ARA6) were found to contribute to natural variation in oil composition and to show differentiation among the subpopulations. Interestingly, population genetic analyses revealed that specific haplotypes of PAL6 and LIN6 have been selected in japonica rice. Based on these results, we propose a possible oil biosynthetic pathway in rice grains. Collectively, our results provide new insights into the genetic basis of oil biosynthesis in rice grains and can facilitate marker-based breeding of rice varieties with enhanced oil and grain quality.

5.
Gene ; 770: 145353, 2021 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-33333227

RESUMO

Since domestication, rice has cultivated in a wide range of latitudes with different day lengths. Selection of diverse natural variations in heading date and photoperiod sensitivity is critical for adaptation of rice to different geographical environments. To unravel the genetic architecture underlying natural variation of rice flowering time, we conducted a genome wide association study (GWAS) using several association analysis strategies with a diverse worldwide collection of 529 O. sativa accessions. Heading date was investigated in three environments under long-day or short-day conditions, and photosensitivity was evaluated. By dividing the whole association panel into subpopulations and performing GWAS with both linear mixed models and multi-locus mixed-models, we revealed hundreds of significant loci harboring novel candidate genes as well as most of the known flowering time genes. In total, 127 hotspots were detected in at least two GWAS. Universal genetic heterogeneity was found across subpopulations. We further detected abundant interactions between GWAS loci, especially in indica. Functional gene families were revealed from enrichment analysis of the 127 hotspots. The results demonstrated a rich of genetic interactions in rice flowering time genes and such epistatic interactions contributed to the large portions of missing heritability in GWAS. It suggests the increased complexity of genetic heterogeneity might discount the power of increasing the sample sizes in GWAS.


Assuntos
Epistasia Genética/fisiologia , Flores , Regulação da Expressão Gênica de Plantas/fisiologia , Genes de Plantas/fisiologia , Oryza , Flores/genética , Flores/crescimento & desenvolvimento , Estudo de Associação Genômica Ampla , Oryza/genética , Oryza/crescimento & desenvolvimento
6.
Plant Sci ; 302: 110715, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33288021

RESUMO

The vascular bundles play important roles in transportation of photoassimilate, and the number, size, and capacity of vascular bundles influence the transportation efficiency. Dissecting the genetic basis may help to make better use of naturally occurring vascular bundle variations. Here, we conducted a genome-wide association study (GWAS) of the vascular bundle variations in a worldwide collection of 529 Oryza sativa accessions. A total of 42 and 93 significant association loci were identified in the neck panicle and flag leaf, respectively. The introgression lines showing extreme values of the target traits harbored at least one GWAS signal, indicating the reliability of the GWAS loci. Based on the data of near-isogenic lines and transgenic plants, Grain number, plant height, and heading date7 (Ghd7) was identified as a major locus for the natural variation of vascular bundles in the neck panicle at the heading stage. In addition, Narrow leaf1 (NAL1) was found to influence the vascular bundles in both the neck panicle and flag leaf, and the effects of the major haplotypes of NAL1 were characterized. The loci or candidate genes identified would help to improve vascular bundle system in rice breeding.


Assuntos
Oryza/genética , Feixe Vascular de Plantas/genética , Genes de Plantas/genética , Genes de Plantas/fisiologia , Introgressão Genética/genética , Estudo de Associação Genômica Ampla , Haplótipos/genética , Desequilíbrio de Ligação/genética , Oryza/anatomia & histologia , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética , Feixe Vascular de Plantas/anatomia & histologia , Locos de Características Quantitativas/genética , Característica Quantitativa Herdável
7.
Science ; 370(6512): 82-89, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33004515

RESUMO

Knowledge of somatic mutation accumulation in normal cells, which is essential for understanding cancer development and evolution, remains largely lacking. In this study, we investigated somatic clonal events in morphologically normal human urothelium (MNU; epithelium lining the bladder and ureter) and identified macroscopic clonal expansions. Aristolochic acid (AA), a natural herb-derived compound, was a major mutagenic driving factor in MNU. AA drastically accelerates mutation accumulation and enhances clonal expansion. Mutations in MNU were widely observed in chromatin remodeling genes such as KMT2D and KDM6A but rarely in TP53, PIK3CA, and FGFR3 KMT2D mutations were found to be common in urothelial cells, regardless of whether the cells experience exogenous mutagen exposure. Copy number alterations were rare and largely confined to small-scale regions, along with copy-neutral loss of heterozygosity. Single AA-associated clones in MNU expanded to a scale of several square centimeters in size.


Assuntos
Ácidos Aristolóquicos/toxicidade , Montagem e Desmontagem da Cromatina/genética , Mutagênicos/toxicidade , Neoplasias da Bexiga Urinária/induzido quimicamente , Neoplasias da Bexiga Urinária/genética , Urotélio/efeitos dos fármacos , Urotélio/patologia , Classe I de Fosfatidilinositol 3-Quinases/genética , Proteínas de Ligação a DNA/genética , Histona Desmetilases/genética , Humanos , Mutagênese , Mutação , Proteínas de Neoplasias/genética , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/genética , Proteína Supressora de Tumor p53/genética
8.
ACS Appl Mater Interfaces ; 12(28): 31575-31581, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32551482

RESUMO

Increasing the antioxidation capability of Ni for the hydrogen oxidation reaction (HOR) is considered important and challenging for alkaline polymer electrolyte fuel cells (APEFCs). Herein, we report a series of Ni-core carbon-shell (Ni@C) catalysts obtained by a vacuum pyrolysis method treated at different temperatures. According to the cyclic voltammetry tests and the HOR tests, Ni@C treated at 500 °C exhibits a much higher Ni core utilization and better catalytic activity toward HOR than the commonly used Ni/C catalyst. Furthermore, X-ray photoelectron spectroscopy characterization shows that a higher percentage of Ni0 appears at the surface of the Ni core of Ni@C than the Ni/C catalyst. The accelerated durability tests, as well as the chronoamperometry tests, suggest that the antioxidation capability of Ni has been obviously improved by the carbon shells. The Raman spectra show that the graphitization degree of the carbon shells might be the key factor affecting the Ni utilization and the HOR catalytic activity of the Ni@C catalysts. The APEFC achieves a peak power density of 160 mW/cm2 using Ni@C-500 °C as the anode, which could also stably discharge for 120 h at 0.7 V.

9.
ACS Appl Mater Interfaces ; 12(17): 19423-19430, 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32264670

RESUMO

SnO2 is an attractive anodic material for advanced lithium-ion batteries (LIBs). However, its low electronic conductivity and large volume change in lithiation/delithiation lead to a poor rate/cycling performance. Moreover, the initial Coulombic efficiencies (CEs) of SnO2 anodes are usually too low to build practical full LIBs. Herein, a two-step hydrothermal synthesis and pyrolysis method is used to prepare a SnO2/C nanocomposite, in which aggregated SnO2 nanosheets and a carbon network are well-interpenetrated with each other. The SnO2/C nanocomposite exhibits a good rate/cycling performance in half-cell tests but still shows a low initial CE of 45%. To overcome this shortage and realize its application in a full-cell assembly, the SnO2/C anode is controllably prelithiated by the lithium-biphenyl reagent and then coupled with a LiCoO2 cathode. The resulting full LIB displays a high capacity of over 98 mAh g-1LCO in 300 cycles at 1 C rate.

10.
Rice (N Y) ; 13(1): 11, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32040640

RESUMO

BACKGROUND: Wild-abortive cytoplasmic male sterility (CMS-WA) and Honglian CMS (CMS-HL) are the two main CMS types utilized in production of three-line hybrid rice in xian/indica (XI) rice. Dissection of the genetic basis of fertility restoration of CMS-WA and CMS-HL in the core germplasm population would provide valuable gene and material resources for development of three-line hybrid combinations. RESULTS: In this study, two F1 populations with CMS-WA and CMS-HL background respectively were developed using 337 XI and aus accessions being paternal parents. Genome-wide association studies on three fertility-related traits of the two populations for two consecutive years revealed that both fertility restoration of CMS-WA and CMS-HL were controlled by a major locus and several minor loci respectively. The major locus for fertility restoration of CMS-WA was co-located with Rf4, and that for fertility restoration of CMS-HL was co-located with Rf5, which are cloned major restorer of fertility (Rf) genes. Furthermore, haplotype analysis of Rf4, Rf5 and Rf6, the three cloned major Rf genes, were conducted using the 337 paternal accessions. Four main haplotypes were identified for Rf4, and displayed different subgroup preferences. Two main haplotypes were identified for Rf5, and the functional type was carried by the majority of paternal accessions. In addition, eight haplotypes were identified for Rf6. CONCLUSIONS: Haplotype analysis of three Rf genes, Rf4, Rf5 and Rf6, could provide valuable sequence variations that can be utilized in marker-aided selection of corresponding genes in rice breeding. Meanwhile, fertility evaluation of 337 accessions under the background of CMS could provide material resources for development of maintainer lines and restorers.

11.
Mol Plant ; 13(4): 650-657, 2020 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-31962168

RESUMO

Speciation has long been regarded as an irreversible process once the reproductive barriers had been established. However, unlike in natural populations, artificial selection might either accelerate or prevent speciation processes in domesticated species. Asian cultivated rice is a target crop for both domestication and artificial breeding; it contains two subspecies of indica and japonica, which usually produce sterile inter-subspecific hybrids due to reproductive barriers. In this study, we constructed the evolutionary trajectory of a reproductive isolation system S5, which regulates fertility in indica-japonica hybrids via three adjacent genes, based on the data of 606 accessions including two cultivated and 11 wild rice species. Although hybrid sterility haplotypes at S5 lead to establishment of a killer-protector reproductive barrier, origin of wide-compatibility haplotypes by complex hybridization and recombination provides an opposing force to reproductive isolation and thus prevents speciation during domestication. Analysis in a diallel set of 209 crosses involving 21 parents showed that the wide-compatibility genotypes largely rescued fertility of indica-japonica hybrids, indicating that the wide-compatibility gene would enable gene flow to maintain species coherence. This counteracting system indicates that combined effects of natural evolution and artificial selection may result in reversible processes of speciation in rice, which may also have implications for genetic improvement of rice.


Assuntos
Domesticação , Especiação Genética , Oryza/genética , Melhoramento Vegetal , Alelos , Genes de Plantas , Loci Gênicos , Variação Genética , Haplótipos , Hibridização Genética , Infertilidade das Plantas/genética , Isolamento Reprodutivo
12.
ACS Appl Mater Interfaces ; 11(44): 41215-41221, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31609584

RESUMO

In this work, we report a novel dual-redox electrochemical capacitor (EC) using a modified viologen (V) as anolyte and bromide (Br) as catholyte. In general, modified viologens are dications. When they are used as anolyte in aqueous dual-redox ECs, only one-electron reduction reaction can occur, because most divalent and monovalent viologens are soluble but zerovalent viologens are insoluble. The insoluble and nonconductive zerovalent viologens will block the surface of the activated carbon electrode from subsequent reactions. The energy densities of the dual-redox ECs using viologens are expected to be greatly improved if those viologens can carry out multiple electron reduction reactions. In this work, 1,1'-bis[3-(trimethylammonio)propyl]-4,4'-bipyridinium (NV4+), a tetra-cationic viologen, has been used as anolyte for dual-redox EC. NV2+ produced by two-electron reduction of NV4+ is highly soluble in aqueous solution, so that two consecutive one-electron reductions of viologen can be utilized in dual-redox ECs. To further solve the cross-diffusion issue of the charging products, Br3- and NV cations, of the positive and the negative electrodes, we have used tetrapropyl ammonium cation (TPA+) to complex Br3-, and quaternized styrene ethylene butylene styrene (SEBS-QA) anion exchange membrane (M) to block the cross-diffusion of NV cation. The obtained NV/TPA/Br-M (NV4+/TPA+/Br- electrolyte with SEBS-QA membrane) dual-redox EC exhibits an average Coulombic efficiency over 99%. It also provides a high specific energy of 87 Wh/kgdry at 1 A/gdry and a peak power density of 4.8 kW/kgdry at 5 A/gdry. The functions of TPA+ and SEBS-QA membrane were characterized and are discussed in detail.

13.
Langmuir ; 35(42): 13607-13613, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31554400

RESUMO

The self-healing feature of gallium (Ga) is unique, making Ga-based materials attract attention for their potential to solve the anode pulverization issue of lithium ion batteries. In this work, a hierarchical two-dimensional (2D) Ga2O3/C structure has been synthesized by a facile NaCl template method. Ga2O3 nanoparticles (3.8 nm) are uniformly embedded in 2D carbon nanosheets. The long horizontal length of the carbon nanosheets (10 µm) provides long-range electron conductivity, and the thin vertical thickness (75 nm) shortens the Li ion diffusion path. Benefited from the integrated 2D structure and the high electron conductivity, the obtained 2D Ga2O3/C nanosheets exhibit excellent overall performance, including high lithium storage capacity (1026 mAh g-1 at 0.5 A g-1), high rate capability (378 mAh g-1 at 10.0 A g-1), and high cyclability (500 cycles at 0.5 A g-1). The lithiation/delithiation mechanism of 2D Ga2O3/C has been further studied with combined electrochemical and ex situ X-ray diffraction methods.

14.
Plant Biotechnol J ; 17(11): 2211-2222, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31004558

RESUMO

Combining ability is a measure for selecting elite parents and predicting hybrid performance in plant breeding. However, the genetic basis of combining ability remains unclear and a global view of combining ability from diverse mating designs is lacking. We developed a North Carolina II (NCII) population of 96 Oryza sativa and four male sterile lines to identify parents of greatest value for hybrid rice production. Statistical analyses indicated that general combining ability (GCA) and specific combining ability (SCA) contributed variously to different agronomic traits. In a genome-wide association study (GWAS) of agronomic traits, GCA and SCA, we identified 34 significant associations (P < 2.39 × 10-7 ). The superior alleles of GCA loci (Ghd8, GS3 and qSSR4) accumulated in parental lines with high GCA and explained 30.03% of GCA variance in grain yield, indicating that molecular breeding of high GCA parental lines is feasible. The distinct distributions of these QTLs contributed to the differentiation of parental GCA in subpopulations. GWAS of SCA identified 12 more loci that showed dominance on corresponding agronomic traits. We conclude that the accumulation of superior GCA and SCA alleles is an important contributor to heterosis and QTLs that greatly contributed to combining ability in our study would accelerate the identification of elite inbred lines and breeding of super hybrids.


Assuntos
Vigor Híbrido , Oryza/genética , Melhoramento Vegetal , Locos de Características Quantitativas , Estudos de Associação Genética , Fenótipo
15.
Sci China Life Sci ; 62(4): 507-516, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30863959

RESUMO

Mendelian inheritance can ensure equal segregation of alleles from parents to offspring, which provides fundamental basis for genetics and molecular biology. Segregation distortion (SD) leads to preferential transmission of certain alleles from generation to generation. Such violation of Mendelian genetic principle is often accompanied by reproductive isolation and eventually speciation. Although SD is observed in a wide range of species from plants to animals, genome-wide dissection of such biased transmission of gametes is rare. Using nine inter-subspecific rice crosses, a genome-wide screen for SD loci is performed, which reveals 61 single-locus quantitative trait loci and 194 digenic interactions showing distorted transmission ratio, among which 24 new SD loci are identified. Biased transmission of alleles is observed in all nine crosses, suggesting that SD exists extensively in rice populations. 72.13% distorted regions are repeatedly detected in multiple populations, and the most prevalent SD hotspot that observed in eight populations is mapped to chromosome 3. Xian alleles are transmitted at higher frequencies than geng alleles in inter-subspecific crosses, which change the genetic composition of the rice populations. Epistatic interaction contributes significantly to the deviation of Mendelian segregation at the whole-genome level in rice, which is distinct from that in animals. These results provide an extensive archive for investigating the genetic basis of SD in rice, which have significant implications in understanding the reproductive isolation and formation of inter-subspecific barriers during the evolution.


Assuntos
Genoma de Planta/genética , Oryza/genética , Recombinação Genética/genética , Alelos , Mapeamento Cromossômico , Cruzamentos Genéticos , Frequência do Gene , Ligação Genética , Genótipo , Locos de Características Quantitativas , Isolamento Reprodutivo
16.
New Phytol ; 223(2): 705-721, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30891753

RESUMO

Wild and cultivated rice show a significant difference in anthocyanin biosynthesis in the leaf. The regulation system of anthocyanin biosynthesis in rice leaf and the causal mechanism of the difference in this biosynthesis between wild and cultivated rice remain largely unknown. In this study, a genome-wide association study and transcriptome analysis were performed to identify the determinant factors and dissect the regulatory system for anthocyanin biosynthesis in rice leaves. OsC1, OsRb and OsDFR were identified as the determinants of anthocyanin biosynthesis in rice leaves. Artificial selection of certain null mutations of OsC1 and OsRb was the main causal mechanism underlying the loss of anthocyanin pigmentation in most cultivated rice. OsP1 and the MYB-bHLH-WD40 complexes regulate anthocyanin biosynthetic genes in rice leaves with partial functional overlap. OsP1 specifically activates upstream biosynthetic genes (OsCHS, OsCHI and OsF3'H) for anthocyanin biosynthesis, whereas the ternary MYB-bHLH-WD40 complex activates all anthocyanin biosynthetic genes including OsCHS, OsCHI, OsF3'H, OsF3H, OsDFR and OsANS. OsC1 and OsRb are tissue-specific regulators that do not influence anthocyanin biosynthesis in the pericarp. Our results reveal the determinant factors, regulatory system and domestication of anthocyanin biosynthesis in rice leaves, and show the potential of engineering anthocyanin biosynthesis in rice.


Assuntos
Antocianinas/biossíntese , Vias Biossintéticas , Domesticação , Oryza/metabolismo , Folhas de Planta/metabolismo , Sequência de Bases , Variação Genética , Estudo de Associação Genômica Ampla , Haplótipos/genética , Oryza/genética , Fenótipo , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas/genética , Transcrição Genética
17.
ACS Appl Mater Interfaces ; 11(9): 8699-8703, 2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30777747

RESUMO

This study reports an ambient-air-tolerant approach for negative electrode prelithiation by using 1 M lithium-biphenyl (Li-Bp)/tetrahydrofuran (THF) solution as the prelithiation reagent. Key to this strategy are the relatively stable nature of 1 M Li-Bp/THF in ambient air and the unique electrochemical behavior of Bp in ether and carbonate solvents. With its low redox potential of 0.41 V vs Li/Li+, Li-Bp can prelithiate various active materials with high efficacy. The successful prelithiation of a phosphrous/carbon composite electrode and the notable improvement in its initial Coulombic efficiency (CE) demonstrates the practicality of this strategy.

18.
Plant Cell ; 30(11): 2720-2740, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30373760

RESUMO

Rice (Oryza sativa) is an important dietary source of both essential micronutrients and toxic trace elements for humans. The genetic basis underlying the variations in the mineral composition, the ionome, in rice remains largely unknown. Here, we describe a comprehensive study of the genetic architecture of the variation in the rice ionome performed using genome-wide association studies (GWAS) of the concentrations of 17 mineral elements in rice grain from a diverse panel of 529 accessions, each genotyped at ∼6.4 million single nucleotide polymorphism loci. We identified 72 loci associated with natural ionomic variations, 32 that are common across locations and 40 that are common within a single location. We identified candidate genes for 42 loci and provide evidence for the causal nature of three genes, the sodium transporter gene Os-HKT1;5 for sodium, Os-MOLYBDATE TRANSPORTER1;1 for molybdenum, and Grain number, plant height, and heading date7 for nitrogen. Comparison of GWAS data from rice versus Arabidopsis (Arabidopsis thaliana) also identified well-known as well as new candidates with potential for further characterization. Our study provides crucial insights into the genetic basis of ionomic variations in rice and serves as an important foundation for further studies on the genetic and molecular mechanisms controlling the rice ionome.


Assuntos
Estudo de Associação Genômica Ampla/métodos , Oryza/genética , Variação Genética/genética , Genótipo , Desequilíbrio de Ligação/genética , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas/genética
19.
Front Plant Sci ; 9: 612, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29868069

RESUMO

Rice seed storage protein (SSP) is an important source of nutrition and energy. Understanding the genetic basis of SSP content and mining favorable alleles that control it will be helpful for breeding new improved cultivars. An association analysis for SSP content was performed to identify underlying genes using 527 diverse Oryza sativa accessions grown in two environments. We identified more than 107 associations for five different traits, including the contents of albumin (Alb), globulin (Glo), prolamin (Pro), glutelin (Glu), and total SSP (Total). A total of 28 associations were located at previously reported QTLs or intervals. A lead SNP sf0709447538, associated for Glu content in the indica subpopulation in 2015, was further validated in near isogenic lines NIL(Zhenshan97) and NIL(Delong208), and the Glu phenotype had significantly difference between two NILs. The association region could be target for map-based cloning of the candidate genes. There were 13 associations in regions close to grain-quality-related genes; five lead single nucleotide polymorphisms (SNPs) were located less than 20 kb upstream from grain-quality-related genes (PG5a, Wx, AGPS2a, RP6, and, RM1). Several starch-metabolism-related genes (AGPS2a, OsACS6, PUL, GBSSII, and ISA2) were also associated with SSP content. We identified favorable alleles of functional candidate genes, such as RP6, RM1, Wx, and other four candidate genes by haplotype analysis and expression pattern. Genotypes of RP6 and RM1 with higher Pro were not identified in japonica and exhibited much higher expression levels in indica group. The lead SNP sf0601764762, repeatedly detected for Alb content in 2 years in the whole association population, was located in the Wx locus that controls the synthesis of amylose. And Alb content was significantly and negatively correlated with amylose content and the level of 2.3 kb Wx pre-mRNA examined in this study. The associations or candidate genes identified would provide new insights into the genetic basis of SSP content that will help in developing rice cultivars with improved grain nutritional quality through marker-assisted breeding.

20.
PLoS Genet ; 14(4): e1007323, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29617374

RESUMO

As a major component of ideal plant architecture, leaf angle especially flag leaf angle (FLA) makes a large contribution to grain yield in rice. We utilized a worldwide germplasm collection to elucidate the genetic basis of FLA that would be helpful for molecular design breeding in rice. Genome-wide association studies (GWAS) identified a total of 40 and 32 QTLs for FLA in Wuhan and Hainan, respectively. Eight QTLs were commonly detected in both conditions. Of these, 2 and 3 QTLs were identified in the indica and japonica subpopulations, respectively. In addition, the candidates of 5 FLA QTLs were verified by haplotype-level association analysis. These results indicate diverse genetic bases for FLA between the indica and japonica subpopulations. Three candidates, OsbHLH153, OsbHLH173 and OsbHLH174, quickly responded to BR and IAA involved in plant architecture except for OsbHLH173, whose expression level was too low to be detected; their overexpression in plants increased rice leaf angle. Together with previous studies, it was concluded that all 6 members in bHLH subfamily 16 had the conserved function in regulating FLA in rice. A comparison with our previous GWAS for tiller angle (TA) showed only one QTL had pleiotropic effects on FLA and TA, which explained low similarity of the genetic basis between FLA and TA. An ideal plant architecture is expected to be efficiently developed by combining favorable alleles for FLA from indica with favorable alleles for TA from japonica by inter-subspecies hybridization.


Assuntos
Genes de Plantas/genética , Genoma de Planta/genética , Oryza/genética , Folhas de Planta/genética , Locos de Características Quantitativas/genética , Mapeamento Cromossômico , Cromossomos de Plantas , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Variação Genética , Genótipo , Haplótipos , Oryza/fisiologia , Fenótipo , Reguladores de Crescimento de Plantas/farmacologia , Folhas de Planta/fisiologia , Plantas Geneticamente Modificadas
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