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1.
Mol Plant Pathol ; 22(10): 1288-1301, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34339585

RESUMO

Plant-parasitic nematodes can cause devastating damage to crops. These nematodes secrete effectors that suppress the host immune responses to enhance their survival. In this study, Mj2G02, an effector from Meloidogyne javanica, is described. In situ hybridization and transcriptional analysis showed that Mj2G02 was highly expressed in the early infection stages and exclusively expressed in the nematode subventral oesophageal gland cells. In planta RNA interference targeting Mj2G02 impaired M. javanica parasitism, and Mj2G02-transgenic Arabidopsis lines displayed more susceptibility to M. javanica. Using an Agrobacterium-mediated transient expression system and plant immune response assays, we demonstrated that Mj2G02 localized in the plant cell nuclei and could suppress Gpa2/RBP-1-induced cell death. Moreover, by RNA-Seq and quantitative reverse transcription PCR analyses, we showed that Mj2G02 was capable of interfering with the host jasmonic acid (JA) signalling pathway. Multiple jasmonate ZIM-domain (JAZ) genes were significantly upregulated, whereas the JAR1 gene and four JA-responsive genes, MYC3, UPI, THI2.1, and WRKY75, were significantly downregulated. In addition, HPLC analysis showed that the endogenous jasmonoyl-isoleucine (JA-Ile) level in Mj2G02-transgenic Arabidopsis lines was significantly decreased compared to that in wildtype plants. Our results indicate that the M. javanica effector Mj2G02 suppresses the plant immune response, therefore facilitating nematode parasitism. This process is probably mediated by a JA-Ile reduction and JAZ enhancement to repress JA-responsive genes.


Assuntos
Arabidopsis , Tylenchoidea , Animais , Arabidopsis/genética , Morte Celular , Ciclopentanos , Oxilipinas , Doenças das Plantas
2.
Hortic Res ; 8(1): 121, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34059652

RESUMO

Coptis chinensis Franch, a perennial herb, is mainly distributed in southeastern China. The rhizome of C. chinensis has been used as a traditional medicine for more than 2000 years in China and many other Asian countries. The pharmacological activities of C. chinensis have been validated by research. Here, we present a de novo high-quality genome of C. chinensis with a chromosome-level genome of ~958.20 Mb, a contig N50 of 1.58 Mb, and a scaffold N50 of 4.53 Mb. We found that the relatively large genome size of C. chinensis was caused by the amplification of long terminal repeat (LTR) retrotransposons. In addition, a whole-genome duplication event in ancestral Ranunculales was discovered. Comparative genomic analysis revealed that the tyrosine decarboxylase (TYDC) and (S)-norcoclaurine synthase (NCS) genes were expanded and that the aspartate aminotransferase gene (ASP5) was positively selected in the berberine metabolic pathway. Expression level and HPLC analyses showed that the berberine content was highest in the roots of C. chinensis in the third and fourth years. The chromosome-level reference genome of C. chinensis provides important genomic data for molecular-assisted breeding and active ingredient biosynthesis.

3.
Plant J ; 104(3): 662-678, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32772482

RESUMO

Acer truncatum (purpleblow maple) is a woody tree species that produces seeds with high levels of valuable fatty acids (especially nervonic acid). However, the lack of a complete genome sequence has limited both basic and applied research on A. truncatum. We describe a high-quality draft genome assembly comprising 633.28 Mb (contig N50 = 773.17 kb; scaffold N50 = 46.36 Mb) with at least 28 438 predicted genes. The genome underwent an ancient triplication, similar to the core eudicots, but there have been no recent whole-genome duplication events. Acer yangbiense and A. truncatum are estimated to have diverged about 9.4 million years ago. A combined genomic, transcriptomic, metabonomic, and cell ultrastructural analysis provided new insights into the biosynthesis of very long-chain monounsaturated fatty acids. In addition, three KCS genes were found that may contribute to regulating nervonic acid biosynthesis. The KCS paralogous gene family expanded to 28 members, with 10 genes clustered together and distributed in the 0.27-Mb region of pseudochromosome 4. Our chromosome-scale genomic characterization may facilitate the discovery of agronomically important genes and stimulate functional genetic research on A. truncatum. Furthermore, the data presented also offer important foundations from which to study the molecular mechanisms influencing the production of nervonic acids.


Assuntos
Acer/genética , Ácidos Graxos Monoinsaturados/metabolismo , Genoma de Planta , Acer/metabolismo , Centrômero/genética , Elementos de DNA Transponíveis , Ácidos Graxos/biossíntese , Ácidos Graxos/genética , Regulação da Expressão Gênica de Plantas , Genômica/métodos , Heterozigoto , Filogenia , Proteínas de Plantas/genética , Sementes/genética , Sementes/metabolismo , Sequenciamento Completo do Genoma
4.
Int J Mol Sci ; 19(10)2018 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-30314376

RESUMO

Macaca is of great importance in evolutionary and biomedical research. Aiming at elucidating genetic diversity patterns and potential biomedical applications of macaques, we characterized single nucleotide variations (SNVs) of six Macaca species based on the reference genome of Macaca mulatta. Using eight whole-genome sequences, representing the most comprehensive genomic SNV study in Macaca to date, we focused on discovery and comparison of nonsynonymous SNVs (nsSNVs) with bioinformatic tools. We observed that SNV distribution patterns were generally congruent among the eight individuals. Outlier tests of nsSNV distribution patterns detected 319 bins with significantly distinct genetic divergence among macaques, including differences in genes associated with taste transduction, homologous recombination, and fat and protein digestion. Genes with specific nsSNVs in various macaques were differentially enriched for metabolism pathways, such as glycolysis, protein digestion and absorption. On average, 24.95% and 11.67% specific nsSNVs were putatively deleterious according to PolyPhen2 and SIFT4G, respectively, among which the shared deleterious SNVs were located in 564⁻1981 genes. These genes displayed enrichment signals in the 'obesity-related traits' disease category for all surveyed macaques, confirming that they were suitable models for obesity related studies. Additional enriched disease categories were observed in some macaques, exhibiting promising potential for biomedical application. Positively selected genes identified by PAML in most tested Macaca species played roles in immune and nervous system, growth and development, and fat metabolism. We propose that metabolism and body size play important roles in the evolutionary adaptation of macaques.


Assuntos
Variação Genética , Estudo de Associação Genômica Ampla , Genômica , Macaca/classificação , Macaca/genética , Polimorfismo de Nucleotídeo Único , Animais , Pesquisa Biomédica , Biologia Computacional/métodos , Éxons , Predisposição Genética para Doença , Genoma , Anotação de Sequência Molecular
5.
Mol Genet Genomics ; 292(3): 537-550, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28160080

RESUMO

Microsatellites are found in taxonomically different organisms, and such repeats are related with genomic structure, function and certain diseases. To characterize microsatellites for macaques, we searched and compared SSRs with 1-6 bp nucleotide motifs in rhesus, cynomolgus and pigtailed macaque. A total of 1395671, 1284929 and 1266348 perfect SSRs were mined, respectively. The most frequent perfect SSRs were mononucleotide SSRs. The most GC-content was in dinucleotide SSRs and the least was in the mononucleotide SSRs. Chromosome size was positively correlated with SSR number and negatively correlated with the relative frequency and density of SSRs. The GC content of chromosome SSRs were negatively correlated with relative frequency of SSRs and GC content of chromosome sequences. The features of microsatellite distribution in assembled genomes of the three species were greatly similar, which revealed that the distributional pattern of microsatellites is probably conservative in genus Macaca. The degenerated number of repeat motifs was found to be different in pentanucleotide and hexanucleotide repeats. Species-specific motifs for each macaque were significantly underrepresented. Overall, SSR frequencies of each chromosome in rhesus macaque were higher than in cynomolgus macaque. The maximum repeat times of mono- to pentanucleotide repeats in cynomolgus macaque was more than other two macaques. These results emphasize the genetic diversity and phylogenetic relationship of genus Macaca species. Our data will be beneficial for comparative genome mapping, understanding the distribution of SSRs and genome structure between these animal models, and provide a foundation for further development and identification of more macaque-specific SSRs.


Assuntos
Composição de Bases/genética , Macaca fascicularis/genética , Macaca mulatta/genética , Macaca nemestrina/genética , Repetições de Microssatélites/genética , Animais , Sequência de Bases , Variação Genética/genética , Análise de Sequência de DNA
6.
Cancer Cytopathol ; 125(2): 91-103, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28001329

RESUMO

BACKGROUND: Secondary malignancies of salivary glands (SMSGs) are among the most common malignant neoplasms to involve the salivary glands. Fine-needle aspiration biopsy (FNAB) of SMSG can present diagnostic challenges. The current report presents the largest such FNAB series to date. METHODS: A search of the pathology database from 6 academic institutions identified 184 FNAB cases of nonlymphomatous SMSG. RESULTS: Of the 184 cases, 171 were of the parotid glands, and 13 were of the submandibular glands; 130 patients were men, and 54 were women, and the mean patient age at diagnosis was 68 years. Metastatic squamous cell carcinoma (SCC) from all sites (n = 87) and melanoma (n = 67) constituted the majority of SMSGs. Less frequent SMSGs were comprised of metastatic carcinomas from distant organs (n = 16), including sites in the breast, lung, kidney, thyroid, pancreatobiliary, prostate, and bladder. Other uncommon SMSGs, including nasopharyngeal carcinoma (n = 3), sarcoma (n = 4), other metastatic skin-derived carcinomas (n = 6), and metastatic chordoma (n = 1), also were observed. Ancillary tests were performed on 37 FNAB specimens (20.1%) to aid the evaluation. One hundred forty-seven specimens (79.9%) had a definitive diagnosis with accurate tumor subtyping, 21 (11.4%) had a definitive malignant diagnosis but without specifying subtype, 9 (4.9%) had an indeterminate diagnosis, and 7 (3.8%) had a false-negative diagnosis. CONCLUSIONS: SMSGs originate predominately from the head and neck and are more common in older men. Overall, the FNAB diagnosis of SMSG is accurate, but diagnostic challenges can be encountered, especially in SCC types of SMSG. Ancillary studies are needed for the definitive diagnosis of challenging cases. Cancer Cytopathol 2017;125:91-103. © 2016 American Cancer Society.


Assuntos
Biópsia por Agulha Fina , Carcinoma de Células Escamosas/patologia , Glândula Parótida/patologia , Neoplasias das Glândulas Salivares/patologia , Adulto , Idoso , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Neoplasias da Mama/secundário , Carcinoma de Células Escamosas/diagnóstico , Feminino , Humanos , Neoplasias Renais/diagnóstico , Neoplasias Renais/patologia , Neoplasias Renais/secundário , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/secundário , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/patologia , Neoplasias da Próstata/secundário , Neoplasias das Glândulas Salivares/diagnóstico , Glândula Submandibular/patologia , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/secundário , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/secundário
7.
Mol Ecol Resour ; 16(4): 1037-49, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26929266

RESUMO

Chicken repeat 1 (CR1), a member of non-LTR retroposon, is an important phylogenetic marker in avian systematics. In this study, we reported several characteristics of CR1 elements in a draft genome of Arborophila rufipectus (Sichuan partridge). According to the analyses of RepeatMasker, approximately 254 966 CR1 elements were identified in A. rufipectus, covering 6.7% of the genome. Subsequently, we selected eighteen novel CR1 elements by comparing the chicken genome, turkey genome and assembled A. rufipectus scaffolds. Here, a combined data set comprising of 22 CR1 loci, mitochondrial genomes and eight unlinked introns was analysed to infer the evolutionary relationships of twelve Phasianidae species. The applicability of CR1 sequences for inferring avian phylogeny relative to mtDNA and intron sequences was investigated as well. Our results elucidated the position of A. rufipectus in Phasianidae with robust supports that it presented a sister clade to Arborophila ardens/Arborophila brunneopectus, and implied that genus Arborophila was in a basal phylogenetic position within Phasianidae and a phylogenetic affinity between Meleagris gallopavo and Pucrasia macrolopha. Therefore, this work not only resolved some of the confounding relationships among Phasianidae, but also suggested CR1 sequences could provide powerful complementary data for phylogeny reconstruction.


Assuntos
Galliformes/classificação , Galliformes/genética , Variação Genética , Filogenia , Retroelementos , Animais , Galinhas , Análise de Sequência de DNA , Perus
8.
Proteins ; 82(9): 2263-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24523098

RESUMO

The ammonia monooxygenase (AMO)/particulate methane monooxygenase (pMMO) superfamily is a diverse group of membrane-bound enzymes of which only pMMO has been characterized on the molecular level. The pMMO active site is believed to reside in the soluble N-terminal region of the pmoB subunit. To understand the degree of structural conservation within this superfamily, the crystal structure of the corresponding domain of an archaeal amoB subunit from Nitrosocaldus yellowstonii has been determined to 1.8 Å resolution. The structure reveals a remarkable conservation of overall fold and copper binding site location as well as several notable differences that may have implications for function and stability.


Assuntos
Domínio Catalítico , Crenarchaeota/enzimologia , Oxirredutases/ultraestrutura , Oxigenases/ultraestrutura , Sequência de Aminoácidos , Azurina/química , Sítios de Ligação , Cobre/química , Cristalografia por Raios X , Modelos Moleculares , Dados de Sequência Molecular , Ligação Proteica , Dobramento de Proteína
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(7): 1897-902, 2013 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-24059197

RESUMO

Under the experimental condition, the hyperspectral reflectance spectra of the mixed pixel of lotus and water body were acquired using the multi-angles dichotic reflex platform and ASD spectrum instrument. The reflectance spectral morphological character index variation of the hyperspectral mixed pixel at different component proportion was analyzed. The conclusions are as follows: the correlation between these morphological indexes was obvious, and the best morphological index was chosen by removing the index whose R2 was greater than 0.5 (R is correlation coefficient); the variation of different morphological index was obvious; the cluster analysis shows that there was a critical value in the progress of the transformation from the pure pixel (water) to mixed pixel. If the proportion was less than the critical value, the reflectance spectra reflected the reflection characteristics of pure pixel; otherwise, it was the reflection of characteristics of mixed pixel.

10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(3): 737-40, 2013 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-23705444

RESUMO

Under the experimental condition of the 50 degree incidence zenith angle and 45 degree detection azimuth, 24 groups of reflectance spectral of the mixed pixel of lotus and water body acquired using the reflex platform and FieldSpec 3 Hi-Res portable spectrum instrument. The hyperspectral space was built based on the reflectance character. The relationship between similarity and the index of lotus area ratio was analyzed using the linear, logarithm and quadratic curve fitting, and the goodness of fitting is 63.6%, 76.2% and 82.9% respectively. According to the real relationship of the mixed pixel spectral vector and the reference spectral, the best fitting model has nonlinear characteristics. The idea that the mixed pixel may have the critical value was proposed on the base of the analysis. The research result will help understand the mixed pixel further, and provide a new direction for unmixing the mixed pixel.


Assuntos
Lotus , Refratometria/instrumentação , Tecnologia de Sensoriamento Remoto/métodos , Análise Espectral/métodos , Água , Modelos Lineares , Refratometria/métodos
11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(1): 182-5, 2013 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-23586252

RESUMO

Nowdays, under the circumstance of global warming, the traditional study of solid-state snow can not meet the current needs. The present paper involves qualitative analysis of the polarization reflectance spectrum of snow in a different melting state. Special attention is paid to the investigation of the relationship among polarization angles, azimuth angles, the light incidence zenith angles, the detection zenith angles and the different types of snowmelt. It turns out that all these factors have certain influences on the polarization reflectance spectrum of different types of snowmelt. At the waveband of the visible light, the polarization reflectance of snowmelt is the largest at 90 degrees, and the smallest at 0 degrees. The wider the detection angles and the incidence angles, the larger the polarization reflectance. Anomalies (unusual phenomena), different from other spectra, occur when the polarization reflectance spectrum of snowmelt is observed at different azimuth angles. The characteristics of polarization spectra at some certain wavebands play an important role in determining the water content of snowmelt, and meanwhile with the increase of which, the polarization reflectance will go down obviously. These rules have laid a solid foundation for the quantitative analysis of snowmelt properties by using polarization spectrum in the future and are also of great importance in fresh water management as well as monitoring natural disasters such as the spring flood.

12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(1): 186-9, 2013 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-23586253

RESUMO

This paper, catering to the need of the study of remote sensing for thermal radiation polarization properties of ground features, detects the thermal radiation multi-angle polarization properties of snow, and makes analysis of effects of four factors, i. e. detecting zenith angle, detecting azimuth angle, bands and polarizing angle, on the thermal radiation properties of snow. The results show that the radiance and brightness temperature of snow increases with the detecting zenith angle. When the detecting zenith angle is greater than 30 degrees, the growth accelerated, and the effect of detecting zenith angle on the brightness temperature of snow is more significant than that of the radiance; the changes in detecting azimuth angle have some effect on the radiance and brightness temperature of snow, and have much influence on the brightness temperature than that of the radiance; the radiance and brightness temperature of snow is significantly affected by the changes in bands, and the effect on the radiance is more significant; the changes in polarizing angle have some effect on the radiance and brightness temperature of the snow, and have much influence on its brightness temperature. The results of the study provide new ideas and methods for the application of remote sensing technology to carrying out the thermal infrared quantitative study of snow, and have important theoretical significance and potential applications.

13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(1): 92-5, 2012 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-22497135

RESUMO

The use of thermal infrared technology to monitor the land surface temperature has received mature development, and the acceleration of urbanization makes the urban heat effect emerge, thus, studies of the thermal radiation characteristics of urban typical surface features make great significance for the analysis of the causes and distribution of the thermal phenomenon. Based on the study of ground measured data of Baoding city, we have found that, the feature types, the observation time and wall orientations are principal factors that exert an influence on the thermal radiation brightness temperature of urban typical surface features. The results show that different types of surface features will significantly affect the brightness temperature, but "different things with the same spectrum" still exists; the observation time has direct impact on the intensity of thermal radiation and to a large extent on the brightness temperature difference of each channel; the brightness temperature of different wall orientations are also different, and the difference changes with the change in observation time. Studies of thermal radiation characteristics of urban typical surface features have theoretical and practical significance, providing basis for thermal infrared remote sensing to monitor the urban heat effect.

14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(2): 449-52, 2012 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-22512188

RESUMO

A study on the reflected and hyperspectral mixed-pixel of aquatic plants and water was given by using a orthogonal experimental design with three factors and two levels. The results of F test suggest that for the single factors, the band and the area ratio of mixed-pixel on the reflected and hyperspectral mixed-pixel of the reflection effects are particularly significant, however, the detector angle had no significant effect under these experimental conditions; For the interaction, the band and the area ratio of mixed-pixel, the detector and the area ratio of mixed-pixel, the effects of these two interactions on the reflected and hyperspectral mixed-pixel are also particularly significant, This study did quantitative analysis of the factors affecting the reflected and hyperspectral mixed-pixel character and their interaction, and provided a new method for the indepth study of mixed-pixel.


Assuntos
Plantas , Análise Espectral , Água
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