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1.
Mol Biol Evol ; 36(5): 875-889, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30861529

RESUMO

The occurrence of parallel speciation strongly implies the action of natural selection. However, it is unclear how general a phenomena parallel speciation is since it was only shown in a small number of animal species. In particular, the adaptive process and mechanisms underlying the process of parallel speciation remain elusive. Here, we used an integrative approach incorporating population genomics, common garden, and crossing experiments to investigate parallel speciation of the wild rice species Oryza nivara from O. rufipogon. We demonstrated that O. nivara originated multiple times from different O. rufipogon populations and revealed that different O. nivara populations have evolved similar phenotypes under divergent selection, a reflection of recurrent local adaptation of ancient O. rufipogon populations to dry habitats. Almost completed premating isolation was detected between O. nivara and O. rufipogon in the absence of any postmating barriers between and within these species. These results suggest that flowering time is a "magic" trait that contributes to both local adaptation and reproductive isolation in the origin of wild rice species. Our study thus demonstrates a convincing case of parallel ecological speciation as a consequence of adaptation to new environments.


Assuntos
Especiação Genética , Oryza/genética , Adaptação Biológica , Ásia Sudeste , Ásia Ocidental , Ecossistema , Fenótipo , Filogeografia , Polimorfismo de Nucleotídeo Único , Isolamento Reprodutivo , Seleção Genética , Sequenciamento Completo do Genoma
2.
J Zhejiang Univ Sci B ; 19(4): 263-273, 2018 Apr..
Artigo em Inglês | MEDLINE | ID: mdl-29616502

RESUMO

Rice leaf color mutants play a great role in research about the formation and development of chloroplasts and the genetic mechanism of the chlorophyll (Chl) metabolism pathway. pgl3 is a rice leaf color mutant derived from Xiushui11 (Oryza sativa L. spp. japonica), treated with ethyl methane sulfonate (EMS). The mutant exhibited a pale-green leaf (pgl) phenotype throughout the whole development as well as reduced grain quality. Map-based cloning of PGL3 revealed that it encodes the chloroplast signal recognition particle 43 kDa protein (cpSRP43). PGL3 affected the Chl synthesis by regulating the expression levels of the Chl synthesis-associated genes. Considerable reactive oxygen species were accumulated in the leaves of pgl3, and the transcription levels of its scavenging genes were down-regulated, indicating that pgl3 can accelerate senescence. In addition, high temperatures could inhibit the plant's growth and facilitate the process of senescence in pgl3.


Assuntos
Clorofila/metabolismo , Oryza/genética , Oryza/fisiologia , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Cloroplastos/metabolismo , Clonagem Molecular , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Temperatura Alta , Mutação , Fenótipo , Fotossíntese , Espécies Reativas de Oxigênio/metabolismo
3.
Mol Biol Evol ; 33(1): 62-78, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26362653

RESUMO

Ecological speciation is a common mechanism by which new species arise. Despite great efforts, the role of gene expression in ecological divergence and speciation is poorly understood. Here, we conducted a genome-wide gene expression investigation of two Oryza species that are evolutionarily young and distinct in ecology and morphology. Using digital gene expression technology and the paired-end RNA sequencing method, we obtained 21,415 expressed genes across three reproduction-related tissues. Of them, approximately 8% (1,717) differed significantly in expression levels between the two species and these differentially expressed genes are randomly distributed across the genome. Moreover, 62% (1,064) of the differentially expressed genes exhibited a signature of directional selection in at least one species. Importantly, the genes with differential expression between species evolved more rapidly at the 5' flanking sequences than the genes without differential expression relative to coding sequences, suggesting that cis-regulatory changes are likely adaptive and play an important role in the ecological divergence of the two species. Finally, we showed evidence of significant differentiation between species in phenotype traits and observed that genes with differential expression were overrepresented with functional terms involving phenotypic and ecological differentiation between the two species, including reproduction- and stress-related characteristics. Our findings demonstrate that ecological speciation is associated with widespread and adaptive alterations in genome-wide gene expression and provide new insights into the importance of regulatory evolution in ecological speciation in plants.


Assuntos
Adaptação Fisiológica/genética , Expressão Gênica/genética , Especiação Genética , Genoma de Planta/genética , Oryza/genética , Oryza/classificação , Fenótipo
4.
Asian J Androl ; 17(3): 503-7, 2015 May-Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25475661

RESUMO

Chinese men should have a higher prostate-specific antigen (PSA) "gray zone" than the traditional value of 2.5-10.0 ng ml-1 since the incidence of prostate cancer (PCa) in Chinese men is relative low. We hypothesized that PSA density (PSAD) could improve the rate of PCa detection in Chinese men with a PSA higher than the traditional PSA "gray zone." A total of 461 men with a PSA between 2.5 and 20.0 ng ml-1 , who had undergone prostatic biopsy at two Chinese centers were included in the analysis. The men were then further divided into groups with a PSA between 2.5-10.0 ng ml-1 and 10.1-20.0 ng ml-1 . Receiver operating characteristic (ROC) curve was used to evaluate the efficacy of PSA and PSAD for the diagnosis of PCa. In men with a PSA of 2.5-10.0 ng ml-1 or 10.1-20.0 ng ml-1 , the areas under the ROC curve were higher for PSAD than for PSA. This was consistent across both centers and the cohort overall. When the entire cohort was considered, the optimal PSAD cut-off for predicting PCa in men with a PSA of 2.5-10.0 ng ml-1 was 0.15 ng ml-1 ml-1 , with a sensitivity of 64.4% and specificity of 64.6%. The optimal cut-off for PSAD in men with a PSA of 10.1-20.0 ng ml-1 was 0.33 ng ml-1 ml-1 , with a sensitivity of 60.3% and specificity of 82.7%. PSAD can improve the effectiveness for PCa detection in Chinese men with a PSA of 2.5-10.0 ng ml-1 (traditional Western PSA "gray zone") and 10.1-20.0 ng ml-1 (Chinese PSA "gray zone").


Assuntos
Grupo com Ancestrais do Continente Asiático , Biomarcadores Tumorais/sangue , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/diagnóstico , Idoso , Biópsia , China/epidemiologia , Estudos de Coortes , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Próstata/patologia , Neoplasias da Próstata/epidemiologia , Curva ROC , Padrões de Referência , Sensibilidade e Especificidade
5.
Saudi Med J ; 35(1): 20-32, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24445886

RESUMO

OBJECTIVE: To evaluate the effectiveness and complications of tension-free vaginal tape (TVT), transobturator tape (TOT), and tension-free vaginal tape-obturator (TVT-O) in a medium- to long-term follow up. METHODS: We searched PubMed, EMBASE, Cochrane database, ClinicalTrials.gov, Google Scholar, and the International Continence Society (ICS) website from August to December 2012 in Guangzhou First People's Hospital, Guangzhou, China. Randomized controlled trials (RCTs) comparing the effectiveness and complications of TVT, TOT, and TVT-O were selected. RESULTS: Forty RCTs were included. The TVT and TOT had similar subjective (risk ratio [RR]: 0.99; 95% confidence interval [CI]: 0.93-1.04), and objective cure rates (RR: 0.96; 95% CI: 0.70-1.32). However, TVT had a reduced risk of groin/thigh pain (RR: 0.33; 95% CI: 0.18-0.59). The subjective (RR: 1.02; 95% CI: 0.97-1.06) and objective cure rates (RR: 1.02; 95% CI: 0.99-1.06) of TVT-O were similar to TVT, but TVT had a higher risk of bladder perforations (RR: 2.29; 95% CI: 1.18-4.45). The TVT-O and TOT had similar subjective (RR: 0.99; 95% CI: 0.93-1.06), and objective cure rates (RR: 1.01; 95% CI: 0.95-1.07). However, TVT-O had a lower risk of vaginal erosion rates (RR: 0.16; 95% CI: 0.03-0.89). CONCLUSION: The subjective and objective cure rates of stress urinary incontinence were similar among TVT, TOT, and TVT-O in a medium- to long-term follow up. The TVT had a higher risk of bladder perforation than TVT-O, and a lower risk of groin/thigh pain than TOT, and TVT-O had a lower risk of vaginal erosion rates than TOT.


Assuntos
Ensaios Clínicos Controlados Aleatórios como Assunto , Estresse Fisiológico , Incontinência Urinária/cirurgia , Equipamentos e Provisões , Feminino , Humanos , Incontinência Urinária/fisiopatologia , Procedimentos Cirúrgicos Urológicos
6.
BMC Genomics ; 14: 649, 2013 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-24059626

RESUMO

BACKGROUND: Copy number variation (CNV) can lead to intra-specific genome variations. It is not only part of normal genetic variation, but also is the source of phenotypic differences. Rice (Oryza sativa L.) is a model organism with a well-annotated genome, but investigation of CNVs in rice lags behind its mammalian counterparts. RESULTS: We comprehensively assayed CNVs using high-density array comparative genomic hybridization in a panel of 20 Asian cultivated rice comprising six indica, three aus, two rayada, two aromatic, three tropical japonica, and four temperate japonica varieties. We used a stringent criterion to identify a total of 2886 high-confidence copy number variable regions (CNVRs), which span 10.28 Mb (or 2.69%) of the rice genome, overlapping 1321 genes. These genes were significantly enriched for specific biological functions involved in cell death, protein phosphorylation, and defense response. Transposable elements (TEs) and other repetitive sequences were identified in the majority of CNVRs. Chromosome 11 showed the greatest enrichment for CNVs. Of subspecies-specific CNVRs, 55.75% and 61.96% were observed in only one cultivar of ssp. indica and ssp. japonica, respectively. Some CNVs with high frequency differences among groups resided in genes underlying rice adaptation. CONCLUSIONS: Higher recombination rates and the presence of homologous gene clusters are probably predispositions for generation of the higher number of CNVs on chromosome 11 by non-allelic homologous recombination events. The subspecies-specific variants are enriched for rare alleles, which suggests that CNVs are relatively recent events that have arisen within breeding populations. A number of the CNVs identified in this study are candidates for generation of group-specific phenotypes.


Assuntos
Variações do Número de Cópias de DNA/genética , Genoma de Planta/genética , Oryza/genética , Ásia , Análise por Conglomerados , Hibridização Genômica Comparativa , Sequência Conservada/genética , Genes de Plantas/genética , Oryza/crescimento & desenvolvimento , Duplicações Segmentares Genômicas , Especificidade da Espécie
7.
Ying Yong Sheng Tai Xue Bao ; 20(5): 1072-8, 2009 May.
Artigo em Chinês | MEDLINE | ID: mdl-19803162

RESUMO

With two rice genotypes (cv. Zhongbu 51 and Azucena) differing in their root-secreted acid phosphatase activity (APA) under low P condition as test materials, an agar culture experiment was conducted to investigate their P utilization from myo-inositol hexaphosphate (IHP) under conditions of sterilization and inoculating with soil microorganisms. Under sterilization, the shoot dry mass, P absorption and P concentration of test genotypes supplied with hexaphosphate (IHP) as the P source were significantly higher than those with no P supply, but significantly lower than those supplied with inorganic P, indicating that rice plants could partly acquire P from IHP under sterilized condition. The root-secreted APA of the two genotypes was significantly higher under low P than under sufficient P supply, and the higher APA of Zhongbu 51 under low P could be one of the mechanisms of higher P utilization capability of Zhongbu 51 than Azucena under deficient P supply. When supplied with high level IHP (0.96 mmol P x L(-1)), the shoot dry mass, P absorption and P concentration of both Zhongbu 51 and Azucena were higher than those when supplied with low level IHP (0.16 mmol P x L(-1)), indicating that substrate availability could be one of the limiting factors to the utilization of phytate by rice. Inoculation with soil microorganisms had no significant effects on the shoot dry mass, P absorption and P concentration of rice plants, regardless of IHP level and rice genotypes, implying that the utilization of IHP by rice could not be improved via inoculation with soil microorganisms.


Assuntos
Fosfatase Ácida/metabolismo , Organofosfatos/metabolismo , Oryza/enzimologia , Oryza/genética , Genótipo , Ácido Fítico/metabolismo , Raízes de Plantas/enzimologia
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