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1.
Small ; 20(8): e2305991, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37858930

RESUMEN

The application of Si anodes is hindered by some critical issues such as large volume changes of bare Si and fragile solid-electrolyte interface (SEI), resulting in low coulombic efficiency and rapid capacity decay. Herein, a multifunctional SEI film with high content of LiF is in situ constructed via the surface grafting of carbon-fluorine functionalized groups on silicon nanoparticles (SiNPs) during cycling. Mechanical study demonstrates that the incorporation of LiF with high modulus and unbroken carbon-fluorine groups with highly elastic guarantee the rigid-soft coupling SEI film on Si electrode. Furthermore, it is demonstrated that the rigid-soft coupling SEI film can effectively accommodate the volume expansion of Si nanoparticles during lithiation process, with the electrode expanding rate of only 114.16% after 100 cycles (263.87% for bare Si without surface modification). Afterward, with the aid of well-designed rigid-soft coupling SEI, the initial Coulomb efficiency of 89.8% is achieved, showing a reversible capacity of 1477 mAh g-1 after 200 cycles at 1.2 A g-1 . This work provides a simple and efficient solution that can potentially facilitate the practical application of Si anodes.

2.
Mol Breed ; 43(12): 84, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38009100

RESUMEN

Drought is one of the major abiotic stresses affecting the maize production worldwide. As a cross-pollination crop, maize is sensitive to water stress at flowering stage. Drought at this stage leads to asynchronous development of male and female flower organ and increased interval between anthesis and silking, which finally causes failure of pollination and grain yield loss. In the present study, the expansin gene ZmEXPA5 was cloned and its function in drought tolerance was characterized. An indel variant in promoter of ZmEXPA5 is significantly associated with natural variation in drought-induced anthesis-silking interval. The drought susceptible haplotypes showed lower expression level of ZmEXPA5 than tolerant haplotypes and lost the cis-regulatory activity of ZmDOF29. Increasing ZmEXPA5 expression in transgenic maize decreases anthesis-silking interval and improves grain yield under both drought and well-watered environments. In addition, the expression pattern of ZmEXPA5 was analyzed. These findings provide insights into the genetic basis of drought tolerance and a promising gene for drought improvement in maize breeding. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-023-01432-x.

3.
Plant J ; 111(6): 1595-1608, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35860955

RESUMEN

cis-Regulatory variations contribute to trait evolution and adaptation during crop domestication and improvement. As the most important harvested organ in maize (Zea mays L.), kernel size has undergone intensive selection for size. However, the associations between maize kernel size and cis-regulatory variations remain unclear. We chose two independent association populations to dissect the genetic architecture of maize kernel size together with transcriptomic and genotypic data. The resulting phenotypes reflected a strong influence of population structure on kernel size. Compared with genome-wide association studies (GWASs), which accounted for population structure and relatedness, GWAS based on a naïve or simple linear model revealed additional associated single-nucleotide polymorphisms significantly involved in the conserved pathways controlling seed size in plants. Regulation analyses through expression quantitative trait locus mapping revealed that cis-regulatory variations likely control kernel size by fine-tuning the expression of proximal genes, among which ZmKL1 (GRMZM2G098305) was transgenically validated. We also proved that the pyramiding of the favorable cis-regulatory variations has contributed to the improvement of maize kernel size. Collectively, our results demonstrate that cis-regulatory variations, together with their regulatory genes, provide excellent targets for future maize improvement.


Asunto(s)
Estudio de Asociación del Genoma Completo , Zea mays , Expresión Génica , Genes Reguladores , Fenotipo , Zea mays/metabolismo
4.
Nat Plants ; 8(7): 750-763, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35851624

RESUMEN

Single-cross maize hybrids display superior heterosis and are produced from crossing two parental inbred lines belonging to genetically different heterotic groups. Here we assembled 1,604 historically utilized maize inbred lines belonging to various female heterotic groups (FHGs) and male heterotic groups (MHGs), and conducted phenotyping and genomic sequencing analyses. We found that the FHGs and MHGs have undergone both convergent and divergent changes for different sets of agronomic traits. Using genome-wide selection scans and association analyses, we identified a large number of candidate genes that contributed to the improvement of agronomic traits of the FHGs and MHGs. Moreover, we observed increased genetic differentiation between the FHGs and MHGs across the breeding eras, and we found a positive correlation between increasing heterozygosity levels in the differentiated genes and heterosis in hybrids. Furthermore, we validated the function of two selected genes and a differentiated gene. This study provides insights into the genomic basis of modern hybrid maize breeding.


Asunto(s)
Vigor Híbrido , Zea mays , Genómica , Fenotipo , Fitomejoramiento , Zea mays/genética
5.
Pak J Med Sci ; 38(3Part-I): 736-742, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35480540

RESUMEN

Objective: To investigate the comparative diagnostic accuracy of cardiac computed tomography (CT) and transoesophageal echocardiography (TEE) for detecting infective endocarditis. Methods: Original publications published in English language before July, 2021 were thoroughly search in PubMed, CENTRAL (Cochrane Central Register of Controlled Trials), and Google Scholar literature databases. Studies were included if they used CT and/or TEE as an index test, presented data on valvular complications related to infective endocarditis, and used surgical findings as to the reference standard. Results: Literature screening identified fifteen studies that fulfilled the inclusion criteria. Meta-analysis showed that CT sensitivity for detecting valvular abscesses was higher than that of TEE [0.88 (95% confidence interval [CI]: 0.82 to 0.94; 11 studies involving 842 subjects) versus 0.74 (95%CI: 0.65 to 0.84) P = 0.015; 12 studies involving 917 subjects]. TEE showed statistically significantly greater sensitivity than CT for detecting valvular vegetation [0.91 (95% CI: 0.84 to 0.97, 11 studies involving 971 subjects) versus 0.80 (95% CI: 0.69 to 0.82), 12 studies involving 915 subjects, P =0.019. In case of leaflet detection, TEE showed statistically significantly higher sensitivity than CT (0.76 vs 0.46, P =0.010). Conclusion: CT performs statistically significantly better than TEE for detecting abscesses while TEE provides statistically significant superior results for detecting vegetation. There is a need for well-designed prospective studies to further corroborate these findings.

6.
Int J Mol Sci ; 23(5)2022 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-35269730

RESUMEN

Tassel branch number (TBN) is one of the important agronomic traits that contribute to the efficiency of seed production and has been selected strongly during the modern maize breeding process. However, the genetic mechanisms of TBN in maize are not entirely clear. In this study, we used a B73 × CML247 recombination inbred lines (RILs) population to detect quantitative trait loci (QTLs) for TBN. A total of four QTLs (qTBN2a, qTBN2b, qTBN4, and qTBN6) and six candidate genes were identified through expression analysis. Further, one of the candidates (GRMZM2G010011, ZmPAT7) encoding an S-acyltransferase was selected to validate its function by CRISPR-Cas9 technology, and its loss-of-function lines showed a significant increase in TBN. A key SNP(-101) variation in the promoter of ZmPAT7 was significantly associated with TBN. A total of 17 distant eQTLs associated with the expression of ZmPAT7 were identified in expression quantitative trait loci (eQTL) analysis, and ZmNAC3 may be a major factor involved in regulating ZmPAT7. These findings of the present study promote our understanding of the genetic basis of tassel architecture and provide new gene resources for maize breeding improvement.


Asunto(s)
Inflorescencia , Zea mays , Variación Genética , Inflorescencia/genética , Fenotipo , Fitomejoramiento , Sitios de Carácter Cuantitativo , Zea mays/genética
7.
Mol Breed ; 41(8): 50, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37309541

RESUMEN

Compact plant-type with small leaf angle has increased canopy light interception, which is conducive to the photosynthesis of the population and higher population yield at high density planting in maize. In this study, a panel of 285 diverse maize inbred lines genotyped with 56,000 SNPs was used to investigate the genetic basis of leaf angle across 3 consecutive years using a genome-wide association study (GWAS). The leaf angle showed broad phenotypic variation and high heritability across different years. Population structure analysis subdivided the panel into four subgroups that correspond to the four major empirical germplasm origins in China, i.e., Tangsipingtou, Reid, Lancaster and P. When tested with the optimal GWAS model, we found that the Q + K model was the best in reducing false positive. In total, 96 SNPs accounting for 5.54-10.44% of phenotypic variation were significantly (P < 0.0001) associated with leaf angle across three years. According to the linkage disequilibrium decay distance, 96 SNPs were binned into 43 QTLs for leaf angle. Seven major QTLs with R2 > 8% stably detected in at least 2 years, and BLUP values were clustered in four genomic regions (bins 2.01, 2.07, 5.06, and 10.04). Seven important candidate genes, Zm00001d001961, Zm00001d006348, Zm00001d006463, Zm00001d017618, Zm00001d024919, Zm00001d025018, and Zm00001d025033 were predicted for the seven stable major QTLs, respectively. The markers identified in this study can be used for molecular breeding for leaf angle, and the candidate genes would contribute to further understanding of the genetic basis of leaf angle. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-021-01241-0.

8.
PLoS One ; 15(4): e0226455, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32275664

RESUMEN

Safety assessment of genetically modified (GM) crops is crucial at the product-development phase before GM crops are placed on the market. Determining characteristics of sequences flanking exogenous insertion sequences is essential for the safety assessment and marketing of transgenic crops. In this study, we used genome walking and whole-genome sequencing (WGS) to identify the flanking sequence characteristics of the SbSNAC1 transgenic drought-tolerant maize line "SbSNAC1-382", but both of the two methods failed. Then, we constructed a genomic fosmid library of the transgenic maize line, which contained 4.18×105 clones with an average insertion fragment of 35 kb, covering 5.85 times the maize genome. Subsequently, three positive clones were screened by pairs of specific primers, and one of the three positive clones was sequenced by using single-molecule real-time (SMRT) sequencing technology. More than 1.95 Gb sequence data (~105× coverage) for the sequenced clone were generated. The junction reads mapped to the boundaries of T-DNA, and the flanking sequences in the transgenic line were identified by comparing all sequencing reads with the maize reference genome and the sequence of the transgenic vector. Furthermore, the putative insertion loci and flanking sequences were confirmed by PCR amplification and Sanger sequencing. The results indicated that two copies of the exogenous T-DNA fragments were inserted at the same genomic site, and the exogenous T-DNA fragments were integrated at the position of Chromosome 5 from 177155650 to 177155696 in the transgenic line 382. In this study, we demonstrated the successful application of the SMRT technology for the characterization of genomic insertion and flanking sequences.


Asunto(s)
Plantas Modificadas Genéticamente/genética , Zea mays/genética , Aclimatación , Elementos Transponibles de ADN , ADN Bacteriano/genética , Sequías , Genoma de Planta , Secuenciación Completa del Genoma
9.
Plant Sci ; 292: 110380, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32005385

RESUMEN

Water deficits are a major constraint on maize growth and yield, and deep roots are one of the major mechanisms of drought tolerance. In this study, four root and shoot traits were evaluated within an association panel consisting of 209 diverse maize accessions under well-watered (WW) and water-stressed (WS) conditions. A significant positive correlation was observed between seminal root length (SRL) under WS treatment and the drought tolerance index (DI) of maize seedlings. The transcriptome profiles of maize seminal roots were compared between four drought-tolerant lines and four drought-sensitive lines under both water conditions to identify genes associated with the drought stress response. After drought stress, 343 and 177 common differentially expressed genes (DEGs) were identified in the drought-tolerant group and drought-sensitive group, respectively. In parallel, a coexpression network underlying SRL was constructed on the basis of transcriptome data, and 10 hub genes involved in two significant associated modules were identified. Additionally, a genome-wide association study (GWAS) of the SRL revealed 62 loci for the two water treatments. By integrating the results of the GWAS, the common DEGs and the coexpression network analysis, 7 promising candidate genes were prioritized for further research. Together, our results provide a foundation for the enhanced understanding of seminal root changes in response to drought stress in maize.


Asunto(s)
Sequías , Genes de Plantas , Estudio de Asociación del Genoma Completo , Transcriptoma , Zea mays/genética , Raíces de Plantas/genética , Raíces de Plantas/crecimiento & desarrollo , Plantones/genética , Plantones/crecimiento & desarrollo , Estrés Fisiológico , Zea mays/crecimiento & desarrollo
10.
Plant Biotechnol J ; 18(4): 1004-1014, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31553822

RESUMEN

Kernel size and morphology are two important yield-determining traits in maize, but their molecular and genetic mechanisms are poorly characterized. Here, we identified a major QTL, qKM4.08, which explains approximately 24.20% of the kernel morphology variance in a recombinant population derived from two elite maize inbred lines, Huangzaosi (HZS, round kernel) and LV28 (slender kernel). Positional cloning and transgenic analysis revealed that qKM4.08 encodes ZmVPS29, a retromer complex component. Compared with the ZmVPS29 HZS allele, the ZmVPS29 LV28 allele showed higher expression in developing kernels. Overexpression of ZmVPS29 conferred a slender kernel morphology and increased the yield per plant in different maize genetic backgrounds. Sequence analysis revealed that ZmVPS29 has been under purifying selection during maize domestication. Association analyses identified two significant kernel morphology-associated polymorphic sites in the ZmVPS29 promoter region that were significantly enriched in modern maize breeding lines. Further study showed that ZmVPS29 increased auxin accumulation during early kernel development by enhancing auxin biosynthesis and transport and reducing auxin degradation and thereby improved kernel development. Our results suggest that ZmVPS29 regulates kernel morphology, most likely through an auxin-dependent process(es).


Asunto(s)
Ácidos Indolacéticos/metabolismo , Proteínas de Plantas/genética , Semillas/crecimiento & desarrollo , Proteínas de Transporte Vesicular/genética , Zea mays/genética , Domesticación , Fenotipo , Fitomejoramiento , Plantas Modificadas Genéticamente , Zea mays/crecimiento & desarrollo
11.
Theor Appl Genet ; 132(12): 3321-3331, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31555888

RESUMEN

KEY MESSAGE: A major QTL controlling kernel row number, qkrnw4, was identified by combining linkage analysis and association mapping. Within qkrnw4, on the basis of its expression and bioinformatics analysis, Zm00001d052910 was supposed to be the candidate gene for kernel row number. Kernel row number (KRN) is an important yield-related trait that affects kernel number in maize. Understanding the genetic basis of KRN is important for increasing maize yields. In the present study, by the use of a near-isogenic line (NIL) that has a B73 background and that consistently displays a low KRN across environments, qkrnw4, a major quantitative trait locus (QTL) associated with KRN within a yield trait-related QTL hotspot in bin 4.08, was finely mapped to an ~ 33-kb interval. Regional association analysis of a nested association mapping population comprising 5000 recombinant inbred lines revealed Zm00001d052910, which encodes a protein with an unknown function, as the important candidate gene responsible for qkrnw4. Different expression levels of this candidate gene in immature ears were detected between the NIL and its recurrent parent. Moreover, the expression of several auxin-related genes was consistent with that of the candidate gene. Furthermore, the potential associations of this candidate gene with well-known inflorescence-related genes were discussed. The results of this study provide important information for the genetic elucidation of KRN variation in maize.


Asunto(s)
Sitios de Carácter Cuantitativo , Semillas/genética , Zea mays/genética , Mapeo Cromosómico , Ligamiento Genético , Fenotipo
12.
Theor Appl Genet ; 132(12): 3309-3320, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31555889

RESUMEN

KEY MESSAGE: Genetic relationships between the phenotypic means and plasticities of kernel size and weight revealed the common genetic control of these traits in maize. Kernel size and weight are crucial components of grain yield in maize, and phenotypic plasticity in these traits facilitates adaptations to changing environments. Elucidating the genetic architecture of the mean phenotypic values and plasticities of kernel size and weight may be essential for breeding climate-robust maize varieties. Here, a maize nested association mapping (CN-NAM) population and association panel were grown in different environments. A joint linkage analysis and genome-wide association mapping were performed for five kernel size and weight phenotypic traits and two phenotypic plasticity measures. The mean phenotypes and plasticities were significantly correlated. The overall results of quantitative trait locus (QTL) and candidate gene analyses indicated moderate and high levels of common genetic control for the two traits. Furthermore, the mean phenotypes or plasticities of the hundred-kernel weight and volume were commonly regulated to a high degree. One pleiotropic locus on chromosome 10 simultaneously controlled the mean phenotypic values and plasticities of kernel size and weight. Therefore, the plasticity of kernel size and weight might be indirectly selected during maize breeding; however, selecting for high or low plasticity in combination with high or low mean phenotypic values of kernel size and weight traits may be difficult.


Asunto(s)
Fenotipo , Sitios de Carácter Cuantitativo , Semillas/crecimiento & desarrollo , Zea mays/genética , Mapeo Cromosómico , Genes de Plantas , Genotipo , Desequilibrio de Ligamiento , Fitomejoramiento
13.
PLoS One ; 14(7): e0219176, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31276526

RESUMEN

Drought has become one of the most serious abiotic stresses influencing crop production worldwide. Understanding the molecular regulatory networks underlying drought adaption and tolerance in crops is of great importance for future breeding. microRNAs (miRNAs), as important components of post-transcriptional regulation, play crucial roles in drought response and adaptation in plants. Here, we report a miRNome analysis of two maize inbred lines with contrasting levels of drought tolerance under soil drought in the field. Differential expression analysis showed 11 and 34 miRNAs were uniquely responded to drought in H082183 (drought tolerant) and Lv28 (drought sensitive), respectively, in leaves. In roots, 19 and 23 miRNAs uniquely responded to drought in H082183 and Lv28, respectively. Expression analysis of these drought-responsive miRNA-mRNA modules revealed miR164-MYB, miR164-NAC, miR159-MYB, miR156-SPL and miR160-ARF showed a negative regulatory relationship. Further analysis showed that the miR164-MYB and miR164-NAC modules in the tolerant line modulated the stress response in an ABA (abscisic acid)-dependent manner, while the miR156-SPL and miR160-ARF modules in the sensitive line participated in the inhibition of metabolism in drought-exposed leaves. Together, our results provide new insight into not only drought-tolerance-related miRNA regulation networks in maize but also key miRNAs for further characterization and improvement of maize drought tolerance.


Asunto(s)
MicroARNs/genética , Estrés Fisiológico/genética , Zea mays/genética , Aclimatación/genética , Adaptación Fisiológica/genética , Sequías , Regulación de la Expresión Génica de las Plantas/genética , Genoma de Planta/genética , Estudio de Asociación del Genoma Completo/métodos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Hojas de la Planta/metabolismo , Proteínas de Plantas/genética , Raíces de Plantas/metabolismo
14.
J Biophotonics ; 12(11): e201900125, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31291061

RESUMEN

The doughnut beam is a spatially structured beam which has been widely used in super-resolution microscopy, laser trapping and so on. However, when it passes through thick scattering medium, aberrations will seriously affect its performance. Currently, adaptive optics (AO) has become one of the most powerful tools to compensate aberrations. However, conventional AO always suffers from limited corrected field of view (FOV). Here, we propose a method with conjugate AO system based on coherent optical adaptive technique. The results show that the corrected FOV can be improved effectively. For a wide range of the optical applications with doughnut beam, our method has potentials in correcting aberrations with high speed in turbid media.(A) Mouse brain slice, (B) the distribution of r PAO , (C) the distribution of r CAO . The vortex beam focus of the blue point in (B) and (C) among a 137.5 × 137.5 µm FOV (D1) ideally, (D2) with scattering, (D3) in pupil AO system and (D4) in conjugate AO system.


Asunto(s)
Microscopía/métodos , Fenómenos Ópticos , Procesamiento de Imagen Asistido por Computador , Relación Señal-Ruido
15.
Opt Express ; 27(12): 16871-16881, 2019 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-31252906

RESUMEN

The doughnut-shaped beam has been widely applied in the field of super-resolution microscopic imaging, micro-nanostructure lithography, ultra-high-density storage, and laser trapping. However, how to maintain the doughnut-shaped focus inside the scattering medium becomes a challenge, due to the wavefront aberrations. Here we demonstrate a machine learning based adaptive optics method to recover the doughnut-shaped focus with high speed. In our method, the relationship between the distorted doughnut-shaped intensity point spread function and the coefficients of the first 15 Zernike modes for phase correction is established. Experimental results show that the wavefront aberration with 101,784 optical control elements can be predicted within ~17 ms even using a personal computer, and 97.5% correction accuracy can be achieved in 200 repeated tests. Besides, we successfully apply this method in the scanning microscopy theoretically. With a large number of optical control elements and fast operation speed, our method may pave the way for many important applications in bioimaging, such as deep tissue stimulated emission depletion (STED) microscopy.

16.
BMC Plant Biol ; 19(1): 201, 2019 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-31096901

RESUMEN

BACKGROUND: The kernel row number (KRN) of an ear is an important trait related to yield and domestication in maize. Exploring the underlying genetic mechanisms of KRN has great research significance and application potential. RESULTS: In the present study, N531 with a KRN of 18-22 and SLN with a KRN of 4-6 were used as the recurrent parent and the donor parent, respectively, to develop two introgression lines (ILs), IL_A and IL_B, both of which have common negative-effect alleles from SLN on chromosomes 1, 5 and 10 and significantly reduced inflorescence meristem (IM) diameter and KRN compared with those of N531. We used RNA-Seq to investigate the transcriptome profiles of 5-mm immature ears of N531, IL_A and IL_B. We identified a total of 2872 differentially expressed genes (DEGs) between N531 and IL_A, 2428 DEGs between N531 and IL_B and 1811 DEGs between IL_A and IL_B. A total of 1252 DEGs were detected as overlapping DEGs, and 89 DEGs were located on the common introgression fragments. Furthermore, three DEGs (Zm00001d013277, Zm00001d015310 and Zm00001d015377) containing three SNPs associated with KRN were identified using regional association mapping. CONCLUSIONS: These results will facilitate our understanding of ear development and provide important candidate genes for further study on KRN.


Asunto(s)
Grano Comestible/crecimiento & desarrollo , Zea mays/genética , Mapeo Cromosómico/métodos , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas/genética , Genes de Plantas/genética , Genes de Plantas/fisiología , Estudios de Asociación Genética , Sitios de Carácter Cuantitativo/genética , Carácter Cuantitativo Heredable , Reacción en Cadena en Tiempo Real de la Polimerasa
17.
Proc Natl Acad Sci U S A ; 116(23): 11480-11489, 2019 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-31101714

RESUMEN

Optical clearing is a versatile approach to improve imaging quality and depth of optical microscopy by reducing scattered light. However, conventional optical clearing methods are restricted in the efficiency-first applications due to unsatisfied time consumption, irreversible tissue deformation, and fluorescence quenching. Here, we developed an ultrafast optical clearing method (FOCM) with simple protocols and common reagents to overcome these limitations. The results show that FOCM can rapidly clarify 300-µm-thick brain slices within 2 min. Besides, the tissue linear expansion can be well controlled by only a 2.12% increase, meanwhile the fluorescence signals of GFP can be preserved up to 86% even after 11 d. By using FOCM, we successfully built the detailed 3D nerve cells model and showed the connection between neuron, astrocyte, and blood vessel. When applied to 3D imaging analysis, we found that the foot shock and morphine stimulation induced distinct c-fos pattern in the paraventricular nucleus of the hypothalamus (PVH). Therefore, FOCM has the potential to be a widely used sample mounting media for biological optical imaging.


Asunto(s)
Imagenología Tridimensional/métodos , Imagen Óptica/métodos , Animales , Astrocitos/citología , Encéfalo/citología , Femenino , Fluorescencia , Masculino , Ratones , Ratones Endogámicos C57BL , Microscopía Fluorescente/métodos , Neuronas/citología
18.
BMC Plant Biol ; 18(1): 366, 2018 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-30567489

RESUMEN

BACKGROUND: The pentatricopeptide repeat (PPR) gene family is one of the largest gene families in land plants (450 PPR genes in Arabidopsis, 477 PPR genes in rice and 486 PPR genes in foxtail millet) and is important for plant development and growth. Most PPR genes are encoded by plastid and mitochondrial genomes, and the gene products regulate the expression of the related genes in higher plants. However, the functions remain largely unknown, and systematic analysis and comparison of the PPR gene family in different maize genomes have not been performed. RESULTS: In this study, systematic identification and comparison of PPR genes from two elite maize inbred lines, B73 and PH207, were performed. A total of 491 and 456 PPR genes were identified in the B73 and PH207 genomes, respectively. Basic bioinformatics analyses, including of the classification, gene structure, chromosomal location and conserved motifs, were conducted. Examination of PPR gene duplication showed that 12 and 15 segmental duplication gene pairs exist in the B73 and PH207 genomes, respectively, with eight duplication events being shared between the two genomes. Expression analysis suggested that 53 PPR genes exhibit qualitative variations in the different genetic backgrounds. Based on analysis of the correlation between PPR gene expression in kernels and kernel-related traits, four PPR genes are significantly negatively correlated with hundred kernel weight, 12 are significantly negatively correlated with kernel width, and eight are significantly correlated with kernel number. Eight of the 24 PPR genes are also located in metaQTL regions associated with yield and kernel-related traits in maize. Two important PPR genes (GRMZM2G353195 and GRMZM2G141202) might be regarded as important candidate genes associated with maize kernel-related traits. CONCLUSIONS: Our results provide a more comprehensive understanding of PPR genes in different maize inbred lines and identify important candidate genes related to kernel development for subsequent functional validation in maize.


Asunto(s)
Grano Comestible/crecimiento & desarrollo , Genes de Plantas/genética , Genoma de Planta/genética , Proteínas de Plantas/genética , Zea mays/genética , Mapeo Cromosómico , Cromosomas de las Plantas/genética , Grano Comestible/genética , Regulación de la Expresión Génica de las Plantas/genética , Genes de Plantas/fisiología , Genoma de Planta/fisiología , Estudio de Asociación del Genoma Completo , Proteínas de Plantas/fisiología , Zea mays/crecimiento & desarrollo
19.
Sci Rep ; 8(1): 6848, 2018 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-29717181

RESUMEN

Southern leaf blight (SLB) and northern leaf blight (NLB) are the two major foliar diseases limiting maize production worldwide. Upon previous study with the nested association mapping (NAM) population, which consist of 5,000 recombinant inbred lines from 25 parents crossed with B73, we expanded the phenotyping environments from the United States (US) to China, and increased the marker densities from 1106 to 7386 SNPs for linkage mapping, and from 1.6 to 28.5 million markers for association mapping. We identified 49 SLB and 48 NLB resistance-related unique QTLs in linkage mapping, and multiple loci in association mapping with candidate genes involved in known plant disease-resistance pathways. Furthermore, an independent natural population with 282 diversified inbred lines were sequenced for four candidate genes selected based on their biological functions. Three of them demonstrated significant associations with disease resistance. These findings provided valuable resources for further implementations to develop varieties with superior resistance for NLB and SLB.


Asunto(s)
Resistencia a la Enfermedad/genética , Ligamiento Genético , Enfermedades de las Plantas/genética , Sitios de Carácter Cuantitativo , Zea mays/genética , China , Mapeo Cromosómico/métodos , Cromosomas de las Plantas , Estudio de Asociación del Genoma Completo/métodos , Genotipo , Polimorfismo de Nucleótido Simple , Estados Unidos
20.
Theor Appl Genet ; 131(2): 437-448, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29143067

RESUMEN

KEY MESSAGE: A major locus conferring kernel cracking in maize was characterized and fine mapped to an interval of 416.27 kb. Meanwhile, combining the results of transcriptomic analysis, the candidate gene was inferred. Seed development requires a proper structural and physiological balance between the maternal tissues and the internal structures of the seeds. In maize, kernel cracking is a disorder in this balance that seriously limits quality and yield and is characterized by a cracked pericarp at the kernel top and endosperm everting. This study elucidated the genetic basis and characterization of kernel cracking. Primarily, a near isogenic line (NIL) with a B73 background exhibited steady kernel cracking across environments. Therefore, deprived mapping populations were developed from this NIL and its recurrent parent B73. A major locus on chromosome 7, qkc7.03, was identified to be associated with the cracking performance. According to a progeny test of recombination events, qkc7.03 was fine mapped to a physical interval of 416.27 kb. In addition, obvious differences were observed in embryo development and starch granule arrangement within the endosperm between the NIL and its recurrent parent upon the occurrence of kernel cracking. Moreover, compared to its recurrent parent, the transcriptome of the NIL showed a significantly down-regulated expression of genes related to zeins, carbohydrate synthesis and MADS-domain transcription factors. The transcriptomic analysis revealed ten annotated genes within the target region of qkc7.03, and only GRMZM5G899476 was differently expressed between the NIL and its recurrent parent, indicating that this gene might be a candidate gene for kernel cracking. The results of this study facilitate the understanding of the potential mechanism underlying kernel cracking in maize.


Asunto(s)
Endospermo/crecimiento & desarrollo , Semillas/crecimiento & desarrollo , Zea mays/genética , Mapeo Cromosómico , Perfilación de la Expresión Génica , Sitios Genéticos , Genotipo , Fenotipo , Zea mays/crecimiento & desarrollo
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