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1.
Plant Biotechnol J ; 21(3): 506-520, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36383026

RESUMO

Southern corn leaf blight (SLB), caused by the necrotrophic pathogen Cochliobolus heterostrophus, is one of the maize foliar diseases and poses a great threat to corn production around the world. Identification of genetic variations underlying resistance to SLB is of paramount importance to maize yield and quality. Here, we used a random-open-parent association mapping population containing eight recombinant inbred line populations and one association mapping panel consisting of 513 diversity maize inbred lines with high-density genetic markers to dissect the genetic basis of SLB resistance. Overall, 109 quantitative trait loci (QTLs) with predominantly small or moderate additive effects, and little epistatic effects were identified. We found 35 (32.1%) novel loci in comparison with the reported QTLs. We revealed that resistant alleles were significantly enriched in tropical accessions and the frequency of about half of resistant alleles decreased during the adaptation process owing to the selection of agronomic traits. A large number of annotated genes located in the SLB-resistant QTLs were shown to be involved in plant defence pathways. Integrating genome-wide association study, transcriptomic profiling, resequencing and gene editing, we identified ZmFUT1 and MYBR92 as the putative genes responsible for the major QTLs for resistance to C. heterostrophus. Our results present a comprehensive insight into the genetic basis of SLB resistance and provide resistant loci or genes as direct targets for crop genetic improvement.


Assuntos
Estudo de Associação Genômica Ampla , Zea mays , Mapeamento Cromossômico/métodos , Zea mays/genética , Doenças das Plantas/genética , Locos de Características Quantitativas
2.
BMC Genomics ; 23(1): 593, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35971070

RESUMO

BACKGROUND: Maize kernel row number (KRN) is one of the most important yield traits and has changed greatly during maize domestication and selection. Elucidating the genetic basis of KRN will be helpful to improve grain yield in maize. RESULTS: Here, we measured KRN in four environments using a nested association mapping (NAM) population named HNAU-NAM1 with 1,617 recombinant inbred lines (RILs) that were derived from 12 maize inbred lines with a common parent, GEMS41. Then, five consensus quantitative trait loci (QTLs) distributing on four chromosomes were identified in at least three environments along with the best linear unbiased prediction (BLUP) values by the joint linkage mapping (JLM) method. These QTLs were further validated by the separate linkage mapping (SLM) and genome-wide association study (GWAS) methods. Three KRN genes cloned through the QTL assay were found in three of the five consensus QTLs, including qKRN1.1, qKRN2.1 and qKRN4.1. Two new QTLs of KRN, qKRN4.2 and qKRN9.1, were also identified. On the basis of public RNA-seq and genome annotation data, five genes highly expressed in ear tissue were considered candidate genes contributing to KRN. CONCLUSIONS: This study carried out a comprehensive analysis of the genetic architecture of KRN by using a new NAM population under multiple environments. The present results provide solid information for understanding the genetic components underlying KRN and candidate genes in qKRN4.2 and qKRN9.1. Single-nucleotide polymorphisms (SNPs) closely linked to qKRN4.2 and qKRN9.1 could be used to improve inbred yield during molecular breeding in maize.


Assuntos
Locos de Características Quantitativas , Zea mays , Mapeamento Cromossômico/métodos , Grão Comestível/genética , Estudo de Associação Genômica Ampla , Fenótipo , Zea mays/genética
3.
BMC Plant Biol ; 22(1): 610, 2022 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-36564751

RESUMO

Lysine-ε-acetylation (Kac) is a reversible post-translational modification that plays important roles during plant-pathogen interactions. Some pathogens can deliver secreted effectors encoding acetyltransferases or deacetylases into host cell to directly modify acetylation of host proteins. However, the function of these acetylated host proteins in plant-pathogen defense remains to be determined. Employing high-resolution tandem mass spectrometry, we analyzed protein abundance and lysine acetylation changes in maize infected with Puccinia polysora (P. polysora) at 0 h, 12 h, 24 h, 48 h and 72 h. A total of 7412 Kac sites from 4697 proteins were identified, and 1732 Kac sites from 1006 proteins were quantified. Analyzed the features of lysine acetylation, we found that Kac is ubiquitous in cellular compartments and preferentially targets lysine residues in the -F/W/Y-X-X-K (ac)-N/S/T/P/Y/G- motif of the protein, this Kac motif contained proteins enriched in basic metabolism and defense-associated pathways during fungal infection. Further analysis of acetylproteomics data indicated that maize regulates cellular processes in response to P. polysora infection by altering Kac levels of histones and non-histones. In addition, acetylation of pathogen defense-related proteins presented converse patterns in signaling transduction, defense response, cell wall fortification, ROS scavenging, redox reaction and proteostasis. Our results provide informative resources for studying protein acetylation in plant-pathogen interactions, not only greatly extending the understanding on the roles of acetylation in vivo, but also providing a comprehensive dynamic pattern of Kac modifications in the process of plant immune response.


Assuntos
Lisina , Zea mays , Lisina/metabolismo , Zea mays/metabolismo , Processamento de Proteína Pós-Traducional , Puccinia , Acetilação , Proteoma/metabolismo
4.
BMC Gastroenterol ; 22(1): 451, 2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36348278

RESUMO

BACKGROUND: The aim of our study was to evaluate the curative effect and safety of stereotactic body radiation therapy (SBRT) in treating hepatocellular carcinoma (HCC) patients with inferior vena cava (IVCTT) and right atrial tumor thrombus (RATT). METHODS: This retrospective study included fifteen advanced HCC patients with IVCTT and RATT who were treated with SBRT between 2013 and 2020. The prescribed dose delivered to the tumor was 45-50 Gy/7-10 fx. We report their treatment responses according to survival time and toxicities. RESULTS: For these patients, the median follow-up time was 15 months (2-52 months). Local tumor control rates of the treated area were 80% at the time of death or at the last follow-up. The 6-month, 12-month, 18-month and 24-month OS rates were 80.0%, 60.0%, 33.3% and 26.7%, respectively. None of these patients died from the toxicity outcomes and complications of SBRT. CONCLUSION: SBRT is an effective option for advanced HCC patients with IVCTT and RATT.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Radiocirurgia , Trombose , Humanos , Carcinoma Hepatocelular/patologia , Veia Cava Inferior/patologia , Radiocirurgia/efeitos adversos , Neoplasias Hepáticas/patologia , Estudos Retrospectivos , Resultado do Tratamento , Trombose/complicações
5.
Plant Dis ; 2022 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-35253492

RESUMO

Maize (Zea mays L.) is a staple food crop worldwide. In July 2021, gray leaf blight was observed on maize leaves in a field located in Panjin (41°7'11.98" N, 122°4'14.57" E), Liaoning Province, China. Nearly 5% of the maize plants were affected in the field. The leaves of the affected plants showed oval to oblong, gray, sunken lesions with yellow or tan margins. The lesions were scattered all over the leaf surface; however, they were absent on the stalks and other parts of the affected plants. To isolate the pathogen, leaf discs (1.25 mm2) excised from the blight lesions were surface-sterilized with 70% ethanol for 30 seconds, followed by 20% NaOCl for 2 minutes and finally rinsed three times with sterilized water. The discs were cultured on potato dextrose agar (PDA) plates supplemented with streptomycin (100 mg/L) and incubated at 25oC under a 12-h photoperiod for 7 days. Six single spore isolates (two per sampled infected leaf) were purified from the PDA culture plates. The fungal colonies of three selected isolates (one per sampled infected leaf; Pj-1, Pj-2, and Pj-3) were dark brown on the PDA plates and devoid of aerial hyphae; all three isolates grew 11 mm/day on the PDA plates. The number of conidia produced by the isolates on the 6-cm PDA plates 7 days after incubation was ranged from 160 x 108 to 208 x 108 (n = 36). Conidia were hyaline, single-celled and ellipsoidal (3.35-3.56 µm [width] x 6.47-6.70 [length] µm; n = 36). To identify the pathogen, four loci, i.e., 28S subunit (large subunit [LSU]) of the nuclear ribosomal (nr) DNA, internal transcribed spacer (ITS) region (ITS1, 5.8S subunit of nrDNA, and ITS2), the second-largest subunit of RNA polymerase II (rpb2) and ß-tubulin (tub2) were amplified using the primer sets described in the study by Chen el al. 2015. BLASTn search against GenBank revealed that the four amplicon sequences originating from Pj-1, Pj-2, and Pj-3 showed 99-100% homology to the type strain CBS 528.66 of D. glomerata. A phylogenetic tree deduced from a maximum likelihood analysis of a concatenated MUSCLE-based alignment of LSU, ITS region, rpb2, and tub2 sequences of 12 isolates/strains showed that the Pj isolates clustered together with CBS 528.66, along with other D. glomerata isolates/strains, with a high bootstrap support value (i.e., 99). Based on both morphological characteristics and molecular phylogeny, Pj-1, Pj-2, and Pj-3 were identified as the D. glomerata isolates. Since the amplicon sequences of the three isolates were identical, only Pj-2 sequences were deposited in GenBank with accession numbers OM372474 (LSU), OK485138 (ITS), OM406188 (rpb2), and OK485135 (tub2). To confirm pathogenicity, 14-day-old plants (V3 growth stage) of a maize cultivar P178 were spray-inoculated with the Pj-2 conidia (1 x 107 conidia/mL) in a growth chamber. The inoculated leaves exhibited typical gray leaf blight lesions (similar to those detected in the maize field) 7 days post-inoculation at 25oC and 95-100% humidity under a 12-h photoperiod, whereas the leaves spray-inoculated with sterilized water remained healthy. The pathogenicity assay was repeated three times; the pathogen was re-isolated from the inoculated leaves each time and confirmed by the morphological characteristics and the molecular phylogeny based on the four loci to be D. glomerata, fulfilling Koch's postulates. This first report of D. glomerata causing Didymella leaf blight on maize will help develop robust disease management strategies against this emerging fungal pathogen.

6.
BMC Genomics ; 21(1): 357, 2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32398006

RESUMO

BACKGROUND: Fusarium ear rot (FER) caused by Fusarium verticillioides is a major disease of maize that reduces grain yield and quality globally. However, there have been few reports of major loci for FER were verified and cloned. RESULT: To gain a comprehensive understanding of the genetic basis of natural variation in FER resistance, a recombinant inbred lines (RIL) population and one panel of inbred lines were used to map quantitative trait loci (QTL) for resistance. As a result, a total of 10 QTL were identified by linkage mapping under four environments, which were located on six chromosomes and explained 1.0-7.1% of the phenotypic variation. Epistatic mapping detected four pairs of QTL that showed significant epistasis effects, explaining 2.1-3.0% of the phenotypic variation. Additionally, 18 single nucleotide polymorphisms (SNPs) were identified across the whole genome by genome-wide association study (GWAS) under five environments. Compared linkage and association mapping revealed five common intervals located on chromosomes 3, 4, and 5 associated with FER resistance, four of which were verified in different near-isogenic lines (NILs) populations. GWAS identified three candidate genes in these consistent intervals, which belonged to the Glutaredoxin protein family, actin-depolymerizing factors (ADFs), and AMP-binding proteins. In addition, two verified FER QTL regions were found consistent with Fusarium cob rot (FCR) and Fusarium seed rot (FSR). CONCLUSIONS: These results revealed that multi pathways were involved in FER resistance, which was a complex trait that was controlled by multiple genes with minor effects, and provided important QTL and genes, which could be used in molecular breeding for resistance.


Assuntos
Mapeamento Cromossômico/métodos , Resistência à Doença/genética , Fusarium/patogenicidade , Estudo de Associação Genômica Ampla , Locos de Características Quantitativas , Zea mays/genética , Fatores de Despolimerização de Actina/genética , Cromossomos de Plantas , Fenótipo , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Polimorfismo de Nucleotídeo Único , Zea mays/microbiologia
7.
Mol Pharm ; 17(4): 1059-1070, 2020 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-31860321

RESUMO

Various types of nanocarriers modified with poly(ethylene glycol) (PEG) exhibit the accelerated blood clearance (ABC) phenomenon, resulting in reduced circulation time and abnormal increase in hepatic and splenic accumulations. Based on the abundance of esterases in the serum of rats, we developed cleavable methoxy PEG-cholesteryl methyl carbonate (mPEG-CHMC) with a carbonate linkage and noncleavable N-(carbonyl-methoxy PEG-n)-1,2-distearoyl-sn-glycero-3-phos-phoethanolamine (mPEG-DSPE) with a carbamate linkage on the surface of the nanoemulsions (CHMCE and PE, respectively). Both PEG derivatives possessed PEG with six different molecular weights (n = 350, 550, 750, 1000, 2000, and 5000). The pharmacokinetic behaviors and biodistributions of single and repeated injection of the two types of PEGylated nanoemulsions were determined to investigate the influence of cleavable linkages and PEG molecular weights on the ABC phenomenon in an attempt to find a potential strategy to eliminate the ABC phenomenon. CHMCEns (n = 1000, 2000, and 5000) exhibited the same pharmacokinetic behaviors as PE550 and PE750 and only alleviated the ABC phenomenon to a certain extent at the expense of shortened cycle time, indicating that the cleavable carbonate linkage was not an ideal strategy to eliminate the ABC phenomenon. As the molecular weights of PEG increased, the ABC phenomenon became more severe. Surprisingly, PE5000 induced a lower anti-PEG IgM level and a weaker ABC phenomenon compared with PE2000 while possessing a similar long circulation time. The results suggested that increasing the molecular weight of PEG in the PEG derivatives could be a potential strategy for eliminating the ABC phenomenon while simultaneously guaranteeing longer circulation time.


Assuntos
Colesterol/metabolismo , Emulsões/metabolismo , Lipídeos/química , Nanopartículas/metabolismo , Fosfolipídeos/metabolismo , Polietilenoglicóis/metabolismo , Animais , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Emulsões/química , Imunoglobulina M/metabolismo , Cinética , Masculino , Taxa de Depuração Metabólica/fisiologia , Peso Molecular , Nanopartículas/química , Polietilenoglicóis/química , Ratos , Ratos Wistar , Baço/metabolismo
8.
Plant Dis ; 104(7): 1944-1948, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32384254

RESUMO

Southern corn rust (SCR) is a prevalent foliar disease that can lead to severe yield losses in maize. Growing SCR-resistant varieties is the most effective way to control the disease. To identify major quantitative trait loci (QTLs) for SCR resistance, a recombinant inbred line population derived from a cross between CIMBL83 (resistant) and Lx9801 (susceptible) was analyzed. The resistance to SCR had high heritability within the population, and a major QTL on chromosome 4 (qSCR4.01), which can explain 48 to 65% of the total phenotypic variation, was consistently detected across multiple environments. Using a progeny-based fine-mapping strategy, we delimited qSCR4.01 to an interval of ∼770 kb. In contrast to other major QTLs for SCR resistance previously reported on the short arm of chromosome 10, qSCR4.01 is a novel QTL and, therefore, a desirable source of SCR resistance in maize breeding programs.


Assuntos
Locos de Características Quantitativas , Zea mays/genética , Mapeamento Cromossômico , Resistência à Doença/genética , Humanos , Doenças das Plantas
9.
BMC Cancer ; 19(1): 846, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31455251

RESUMO

BACKGROUND: To explore the association between biologically effective dose (BED) and survival rates in Child-Pugh A classification (CP-A) small hepatocellular carcinoma (HCC) patients treated with stereotactic body radiation therapy (SBRT). METHODS: This retrospective study included 108 small HCC patients who were treated with SBRT between 2011 and 2014. The prescribed dose delivered to the tumor were 48Gy/8f, 49Gy/7f, 50Gy/5f and 54Gy/6f. The median biologically effective dose (BED10) of the total prescribed dose was 100Gy (76.8-102.6Gy). Factors associated with the survival rate were examined using the Cox proportion hazards model, and the factors associated with radiation-induced liver injury (RILD) were examined by logistic regression analysis. RESULTS: For these patients, the median follow-up time was 42 months (6-77 months), and the 1-, 2- and 3-year overall survival (OS) rates were 96.3, 89.8 and 80.6%, respectively. The 1-, 2- and 3-year progression-free survival (PFS) rates were 85.2, 70.1 and 60.6%, respectively. The 1-, 2- and 3-year local control (LC) rates were 98.1, 96.2 and 95.1%, respectively. The 1-, 2- and 3-year distant metastasis- free survival (DMFS) rates were 86.1, 72.8 and 61.2%. The OS, PFS and DMFS were significantly higher in the BED10 ≥ 100Gy group than in the BED10 < 100Gy group (OS: p = 0.020; PFS: p = 0.017; DMFS: p = 0.012). The PLT count was a predictive factor of RILD. CONCLUSIONS: SBRT is a safe and effective option for CP-A HCC patients. A BED10 value greater than 100Gy and lower CP score are associated with improved OS and PFS. Additionally, the peripheral PLT count are predictive factors of RILD.


Assuntos
Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/radioterapia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/radioterapia , Radiocirurgia , Dosagem Radioterapêutica , Adulto , Idoso , Biomarcadores Tumorais , Carcinoma Hepatocelular/mortalidade , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Lesões por Radiação/diagnóstico , Lesões por Radiação/etiologia , Radiocirurgia/efeitos adversos , Radiocirurgia/métodos , Recidiva , Retratamento , Resultado do Tratamento , Carga Tumoral
10.
Pharm Res ; 36(12): 176, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31686241

RESUMO

PURPOSE: This study aimed to explore the potential of sialic acid - related selectin targeting strategy in the treatment of leukemia and some solid tumors. We expected it could "actively" bind tumor cells and kill them, reducing non-specific toxicity to normal cells. METHODS: BOR-SA prodrug was synthesized by reacting an ortho-dihydroxy group in SA with a boronic acid group in BOR. Two kinds of leukemia cells (RAW264.7 and HL60 cells), one solid sarcoma cell model (S180 cells) and their corresponding normal cells (monocytes (MO), neutrophil (NE) and fibroblast (L929)) were selected for the in vitro cell experiments (cytotoxicity, cellular uptake, cell cycle and apoptosis experiments). The S180 tumor-bearing Kunming mice model was established for anti-tumor pharmacodynamic experiments. RESULTS: In vitro cell assay results showed that uptake of BOR-SA by HL60 and S180 cells were increased compared with the control group. BOR-SA induced a lower IC50, higher ratio of apoptosis and cell cycle arrest of tumor cells. In vivo anti-S180 tumor pharmacodynamics experiments showed that mice in the BOR-SA group had higher tumor inhibition rate, higher body weight and lower immune organ toxicity compared with the control group. CONCLUSIONS: sialic acid-mediated selectin targeting strategy may have great potential in the treatment of related tumors.


Assuntos
Antineoplásicos/farmacocinética , Bortezomib/farmacocinética , Leucemia/tratamento farmacológico , Ácido N-Acetilneuramínico/química , Pró-Fármacos/farmacocinética , Selectinas/metabolismo , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/síntese química , Apoptose/efeitos dos fármacos , Bortezomib/administração & dosagem , Bortezomib/síntese química , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Masculino , Manitol/química , Manitol/metabolismo , Camundongos , Terapia de Alvo Molecular/métodos , Ácido N-Acetilneuramínico/metabolismo , Pró-Fármacos/administração & dosagem , Pró-Fármacos/síntese química , Selectinas/genética
11.
Mol Pharm ; 15(12): 5534-5545, 2018 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-30392377

RESUMO

With increasing application of PEGylated products, drawbacks are beginning to emerge such as the "PEG dilemma". Other promising materials may need to be found in the current situation. Endogenous polysialic acid (PSA), which is highly expressed on mammalian, bacterial, and malignant surface, may be a promising material in oncology. In this study, a dual-responsive amphiphilic PSA cholesterol derivative (PSA-CS-CH) was synthesized to explore the opportunity of PSA in targeted drug delivery systems. PSA-CS-CH, F127 mixed micelles (PF-M), and pure F127 micelles (F-M) were prepared for comparative antitumor experiments. The in vitro experiments showed that modification of PSA-CS-CH significantly increased cytotoxicity and cellular uptake. PF-M had excellent tumor microenvironment response release behavior on acidic media with high GSH levels. The in vivo fluorescence imaging and antitumor experiments showed that PF-M had excellent tumor targeting ability and great tumor suppression ability. In summary, biodegradable PSA may contribute to cancer therapy.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Portadores de Fármacos/química , Neoplasias/tratamento farmacológico , Animais , Antibióticos Antineoplásicos/farmacocinética , Linhagem Celular Tumoral/transplante , Colesterol/química , Modelos Animais de Doenças , Doxorrubicina/farmacocinética , Liberação Controlada de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Estabilidade de Medicamentos , Humanos , Concentração de Íons de Hidrogênio , Microscopia Intravital , Masculino , Camundongos , Micelas , Microscopia de Fluorescência , Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Oxirredução , Polietilenos/química , Polipropilenos/química , Ratos , Ratos Wistar , Ácidos Siálicos/química
12.
BMC Plant Biol ; 15: 206, 2015 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-26289207

RESUMO

BACKGROUND: Northern corn leaf blight (NCLB) caused by Exserohilum turcicum is a destructive disease in maize. Using host resistance to minimize the detrimental effects of NCLB on maize productivity is the most cost-effective and appealing disease management strategy. However, this requires the identification and use of stable resistance genes that are effective across different environments. RESULTS: We evaluated a diverse maize population comprised of 999 inbred lines across different environments for resistance to NCLB. To identify genomic regions associated with NCLB resistance in maize, a genome-wide association analysis was conducted using 56,110 single-nucleotide polymorphism markers. Single-marker and haplotype-based associations, as well as Anderson-Darling tests, identified alleles significantly associated with NCLB resistance. The single-marker and haplotype-based association mappings identified twelve and ten loci (genes), respectively, that were significantly associated with resistance to NCLB. Additionally, by dividing the population into three subgroups and performing Anderson-Darling tests, eighty one genes were detected, and twelve of them were related to plant defense. Identical defense genes were identified using the three analyses. CONCLUSION: An association panel including 999 diverse lines was evaluated for resistance to NCLB in multiple environments, and a large number of resistant lines were identified and can be used as reliable resistance resource in maize breeding program. Genome-wide association study reveals that NCLB resistance is a complex trait which is under the control of many minor genes with relatively low effects. Pyramiding these genes in the same background is likely to result in stable resistance to NCLB.


Assuntos
Mapeamento Cromossômico , Resistência à Doença/genética , Estudo de Associação Genômica Ampla , Doenças das Plantas/genética , Folhas de Planta/microbiologia , Zea mays/genética , Zea mays/microbiologia , Análise de Variância , Cromossomos de Plantas/genética , Genes de Plantas , Estudos de Associação Genética , Loci Gênicos , Haplótipos/genética , Padrões de Herança/genética , Anotação de Sequência Molecular , Fenótipo , Doenças das Plantas/microbiologia , Folhas de Planta/genética , Polimorfismo de Nucleotídeo Único/genética
13.
J Integr Plant Biol ; 57(12): 1046-62, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25881980

RESUMO

In this study, we considered five categories of molecular markers in clonal F1 and double cross populations, based on the number of distinguishable alleles and the number of distinguishable genotypes at the marker locus. Using the completed linkage maps, incomplete and missing markers were imputed as fully informative markers in order to simplify the linkage mapping approaches of quantitative trait genes. Under the condition of fully informative markers, we demonstrated that dominance effect between the female and male parents in clonal F1 and double cross populations can cause the interactions between markers. We then developed an inclusive linear model that includes marker variables and marker interactions so as to completely control additive effects of the female and male parents, as well as the dominance effect between the female and male parents. The linear model was finally used for background control in inclusive composite interval mapping (ICIM) of quantitative trait locus (QTL). The efficiency of ICIM was demonstrated by extensive simulations and by comparisons with simple interval mapping, multiple-QTL models and composite interval mapping. Finally, ICIM was applied in one actual double cross population to identify QTL on days to silking in maize.


Assuntos
Mapeamento Cromossômico/métodos , Cruzamentos Genéticos , Locos de Características Quantitativas/genética , Zea mays/genética , Cromossomos de Plantas/genética , Células Clonais , Simulação por Computador , Marcadores Genéticos , Genética Populacional , Endogamia , Modelos Genéticos
14.
ACS Biomater Sci Eng ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38869358

RESUMO

DNA vaccines represent an innovative approach for the immunization of diverse diseases. However, their clinical trial outcomes are constrained by suboptimal transfection efficiency and immunogenicity. In this work, we present a universal methodology involving the codelivery of Toll-like receptor 7/8 agonists (TLR7/8a) and antigen gene using TLR7/8a-conjugated peptide-coated poly(ß-amino ester) (PBAE) nanoparticles (NPs) to augment delivery efficiency and immune response. Peptide-TLR7/8a-coated PBAE NPs exhibit advantageous biophysical attributes, encompassing diminutive particle dimensions, nearly neutral ζ potential, and stability in the physiological environment. This synergistic approach not only ameliorates the stability of plasmid DNA (pDNA) and gene delivery efficacy but also facilitates subsequent antigen production. Furthermore, under optimal formulation conditions, the TLR7/8a-conjugated peptide coated PBAE NPs exhibit a potent capacity to induce robust immune responses. Collectively, this nanoparticulate gene delivery system demonstrates heightened transfection efficacy, stability, biodegradability, immunostimulatory effect, and low toxicity, making it a promising platform for the clinical advancement of DNA vaccines.

15.
ACS Nano ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953884

RESUMO

The therapeutic efficacy of oncolytic adenoviruses (OAs) relies on efficient viral transduction and replication. However, the limited expression of coxsackie-adenovirus receptors in many tumors, along with the intracellular antiviral signaling, poses significant obstacles to OA infection and oncolysis. Here, we present sonosensitizer-armed OAs (saOAs) that potentiate the antitumor efficacy of oncolytic virotherapy through sonodynamic therapy-augmented virus replication. The saOAs could not only efficiently infect tumor cells via transferrin receptor-mediated endocytosis but also exhibit enhanced viral replication and tumor oncolysis under ultrasound irradiation. We revealed that the sonosensitizer loaded on the viruses induced the generation of ROS within tumor cells, which triggered JNK-mediated autophagy, ultimately leading to the enhanced viral replication. In mouse models of malignant melanoma, the combination of saOAs and sonodynamic therapy elicited a robust antitumor immune response, resulting in significant inhibition of melanoma growth and improved host survival. This work highlights the potential of sonodynamic therapy in enhancing the effectiveness of OAs and provides a promising platform for fully exploiting the antitumor efficacy of oncolytic virotherapy.

16.
Int J Biol Macromol ; 245: 125462, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37336378

RESUMO

Colletotrichum graminicola causes anthracnose on maize, an economically significant disease worldwide. To decipher how the pathogen controls its virulence/pathogenicity on maize at the minichromosomal level, we sequenced the genome and transcriptome of the C. graminicola strain T1-3-3. The 61.91 Mb genome contains three transcriptionally repressed, full-length strain-specific minichromosomes (<1 Mb; Chr11 through Chr13). A CRISPR/Cas9-based system was developed to knock out large chromosomal segments; it involved the generation of multiple simultaneous DNA double-strand breaks across a targeted genomic region, followed by homology-directed replacement thereof with a donor DNA template carrying the selectable marker hygromycin phosphotransferase gene flanked by homologous sequence arms of the targeted region. Using this system, we obtained distinct mutants functionally nullisomic for individual minichromosomes. Only the ΔChr12 mutant lacking the 498.44 Kb genomic region carrying all of the 31 genes of Chr12 exhibited attenuated virulence on maize and was indistinguishable from T1-3-3 in fungal growth and conidiation, indicating that Chr12 is a conditionally dispensable minichromosome and imparts full virulence to C. graminicola on maize. The CRISPR/Cas9-mediated genome editing system developed in this study will enable the determination of the biological functions of minichromosomes or large chromosomal segments in fungal plant pathogens.


Assuntos
Sistemas CRISPR-Cas , Zea mays , Virulência/genética , Zea mays/genética , Zea mays/microbiologia , Sistemas CRISPR-Cas/genética , DNA
17.
Acta Pharm Sin B ; 13(1): 425-439, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36815045

RESUMO

Immunoscenescence plays a key role in the initiation and development of tumors. Furthermore, immunoscenescence also impacts drug delivery and cancer therapeutic efficacy. To reduce the impact of immunosenescence on anti-tumor therapy, this experimental plan aimed to use neutrophils with tumor tropism properties to deliver sialic acid (SA)-modified liposomes into the tumor, kill tumor cells via SA-mediated photochemotherapy, enhance infiltration of neutrophils into the tumor, induce immunogenic death of tumor cells with chemotherapy, enhance infiltration of CD8+ T cells into the tumor-draining lymph nodes and tumors of immunosenescent mice, and achieve SA-mediated photochemotherapy. We found that CD8+ T cell and neutrophil levels in 16-month-old mice were significantly lower than those in 2- and 8-month-old mice; 16-month-old mice exhibited immunosenescence. The anti-tumor efficacy of SA-mediated non-photochemotherapy declined in 16-month-old mice, and tumors recurred after scabbing. SA-mediated photochemotherapy enhanced tumor infiltration by CD8+ T cells and neutrophils, induced crusting and regression of tumors in 8-month-old mice, inhibited metastasis and recurrence of tumors and eliminated the immunosenescence-induced decline in antitumor therapeutic efficacy in 16-month-old mice via the light-heat-chemical-immunity conversion.

18.
ACS Appl Mater Interfaces ; 15(1): 67-76, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36508395

RESUMO

Glioblastoma is the most common type of primary brain tumor, which has a high recurrence rate and a high mortality rate. Immunotherapy shows promise in cancer therapy due to its capacity to manipulate the immune system to attack tumor cells with less toxic and durable immune responses. However, the low immunogenicity and limited immune cell infiltration in a glioblastoma lead to a weakened antitumor immune response, resulting in suboptimal therapeutic efficacy. A compelling solution is provided by oncolytic adenovirus (OAs), which can selectively replicate within tumor cells while simultaneously promoting antitumor immunity. Herein, we constructed an oncolytic adenovirus reservoir (OAR) by shocking OA-loaded tumor cells in liquid nitrogen to eliminate proliferation and pathogenicity. OARs showed sustained OAs release and effectively lysed tumor cells in vitro and in vivo. In a mouse intracranial glioblastoma model, OARs could efficiently induce dendritic cells' maturation, facilitate the tumor recruitment, and promote the infiltration of cytotoxic effector T lymphocytes via a single treatment, resulting in specific antitumor immune responses and long-term animal survival. Taken together, these results demonstrated that OAR is a promising synergistic therapeutic strategy for treating glioblastoma.


Assuntos
Adenoviridae , Glioblastoma , Camundongos , Animais , Adenoviridae/genética , Linhagem Celular Tumoral , Glioblastoma/terapia , Imunoterapia/métodos , Linfócitos T Citotóxicos
19.
Front Plant Sci ; 14: 1221395, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37810381

RESUMO

Southern corn rust (SCR) caused by Puccinia polysora Underw is a major disease leading to severe yield losses in China Summer Corn Belt. Using six multi-locus GWAS methods, we identified a set of SCR resistance QTNs from a diversity panel of 140 inbred lines collected from China Summer Corn Belt. Thirteen QTNs on chromosomes 1, 2, 4, 5, 6, and 8 were grouped into three types of allele effects and their associations with SCR phenotypes were verified by post-GWAS case-control sampling, allele/haplotype effect analysis. Relative resistance (RRR) and relative susceptibility (RRs) catering to its inbred carrier were estimated from single QTN and QTN-QTN combos and epistatitic effects were estimated for QTN-QTN combos. By transcriptomic annotation, a set of candidate genes were predicted to be involved in transcriptional regulation (S5_145, Zm00001d01613, transcription factor GTE4), phosphorylation (S8_123, Zm00001d010672, Pgk2- phosphoglycerate kinase 2), and temperature stress response (S6_164a/S6_164b, Zm00001d038806, hsp101, and S5_211, Zm00001d017978, cellulase25). The breeding implications of the above findings were discussed.

20.
Science ; 382(6674): eadg8940, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38033071

RESUMO

The origins of maize were the topic of vigorous debate for nearly a century, but neither the current genetic model nor earlier archaeological models account for the totality of available data, and recent work has highlighted the potential contribution of a wild relative, Zea mays ssp. mexicana. Our population genetic analysis reveals that the origin of modern maize can be traced to an admixture between ancient maize and Zea mays ssp. mexicana in the highlands of Mexico some 4000 years after domestication began. We show that variation in admixture is a key component of maize diversity, both at individual loci and for additive genetic variation underlying agronomic traits. Our results clarify the origin of modern maize and raise new questions about the anthropogenic mechanisms underlying dispersal throughout the Americas.


Assuntos
Produtos Agrícolas , Domesticação , Hibridização Genética , Zea mays , México , Fenótipo , Zea mays/genética , Variação Genética , Produtos Agrícolas/genética
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