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1.
Plant Biotechnol J ; 17(5): 945-955, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30407717

RESUMO

Although efforts have been taken to exploit diversity for yield and quality improvements, limited progress on using beneficial alleles in domesticated and undomesticated cotton varieties is limited. Given the complexity and limited amount of genomic information since the completion of four cotton genomes, characterizing significant variations and haplotype block inheritance under artificial selection has been challenging. Here we sequenced Gossypium hirsutum L. cv CRI-12 (the cotton variety with the largest acreage in China), its parental cultivars, and progeny cultivars, which were bred by the different institutes in China. In total, 3.3 million SNPs were identified and 118, 126 and 176 genes were remarkably correlated with Verticillium wilt, salinity and drought tolerance in CRI-12, respectively. Transcriptome-wide analyses of gene expression, and functional annotations, have provided support for the identification of genes tied to these tolerances. We totally discovered 58 116 haplotype blocks, among which 23 752 may be inherited and 1029 may be recombined under artificial selection. This survey of genetic diversity identified loci that may have been subject to artificial selection and documented the haplotype block inheritance and recombination, shedding light on the genetic mechanism of artificial selection and guiding breeding efforts for the genetic improvement of cotton.


Assuntos
Genes de Plantas/genética , Gossypium/genética , Haplótipos/genética , Melhoramento Vegetal/métodos , Recombinação Genética/genética , Resistência à Doença/genética , Genes de Plantas/fisiologia , Genoma de Planta/genética , Gossypium/crescimento & desenvolvimento , Polimorfismo de Nucleotídeo Único/genética , Característica Quantitativa Herdável , Análise de Sequência de DNA
2.
Nat Commun ; 4: 1858, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23673643

RESUMO

The Tibetan antelope (Pantholops hodgsonii) is endemic to the extremely inhospitable high-altitude environment of the Qinghai-Tibetan Plateau, a region that has a low partial pressure of oxygen and high ultraviolet radiation. Here we generate a draft genome of this artiodactyl and use it to detect the potential genetic bases of highland adaptation. Compared with other plain-dwelling mammals, the genome of the Tibetan antelope shows signals of adaptive evolution and gene-family expansion in genes associated with energy metabolism and oxygen transmission. Both the highland American pika, and the Tibetan antelope have signals of positive selection for genes involved in DNA repair and the production of ATPase. Genes associated with hypoxia seem to have experienced convergent evolution. Thus, our study suggests that common genetic mechanisms might have been utilized to enable high-altitude adaptation.


Assuntos
Antílopes/genética , Genoma/genética , Adaptação Fisiológica/genética , Altitude , Animais , Sequência de Bases , Evolução Molecular , Ontologia Genética , Heterozigoto , Dados de Sequência Molecular , Família Multigênica/genética , Polimorfismo de Nucleotídeo Único/genética , Seleção Genética , Análise de Sequência de DNA , Tibet , Ursidae/genética
3.
Genome Biol ; 14(3): R29, 2013 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-23537097

RESUMO

BACKGROUND: The mechanism of high-altitude adaptation has been studied in certain mammals. However, in avian species like the ground tit Pseudopodoces humilis, the adaptation mechanism remains unclear. The phylogeny of the ground tit is also controversial. RESULTS: Using next generation sequencing technology, we generated and assembled a draft genome sequence of the ground tit. The assembly contained 1.04 Gb of sequence that covered 95.4% of the whole genome and had higher N50 values, at the level of both scaffolds and contigs, than other sequenced avian genomes. About 1.7 million SNPs were detected, 16,998 protein-coding genes were predicted and 7% of the genome was identified as repeat sequences. Comparisons between the ground tit genome and other avian genomes revealed a conserved genome structure and confirmed the phylogeny of ground tit as not belonging to the Corvidae family. Gene family expansion and positively selected gene analysis revealed genes that were related to cardiac function. Our findings contribute to our understanding of the adaptation of this species to extreme environmental living conditions. CONCLUSIONS: Our data and analysis contribute to the study of avian evolutionary history and provide new insights into the adaptation mechanisms to extreme conditions in animals.


Assuntos
Adaptação Fisiológica/genética , Altitude , Genoma/genética , Passeriformes/genética , Animais , Sequência de Bases , Evolução Molecular , Anotação de Sequência Molecular , Fases de Leitura Aberta/genética , Filogenia , Seleção Genética , Análise de Sequência de DNA , Especificidade da Espécie , Sintenia/genética
4.
Bioorg Med Chem ; 14(18): 6349-58, 2006 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-16777417

RESUMO

Betulonic acid, derived from betulinol, a pentacyclic styrene, has shown a highly specific anti-prostate cancer activity in in vitro cell cultures. However, due to the lack of solubility of betulonic acid in aqueous medium, its potent anti-cancer activity in vivo has not been determined to the fullest extent. The present study describes the chemical synthesis of hydrophilic Boc-lysinated-betulonic acid, which has improved its solubility in an aqueous biocompatible solvent. Evaluation in cytotoxicity assays, Boc-lysinated-betulonic acid dissolved in phosphate-buffered saline (PBS) containing 22% ethanol and 4% human serum albumin, has shown 95.7% inhibition of LNCaP prostate cancer cells in culture after 72 h incubation at a concentration of 100 microM, but with little effect on normally proliferating fibroblast cells. In the in vivo assay, male athymic mice transplanted with human prostate LNCaP xenografts were injected with Boc-lysinated-betulonic acid intraperitoneally at a dose of 30 mg/kg daily for 17 days. The treated mice exhibited 92% inhibition of tumor growth as compared to controls. Histological sections of the tumors showed that Boc-lysinated-betulonic acid arrested mitosis and induced apoptosis, which was confirmed by TUNEL assay, Yo-Pro-1 staining, and the release of cleaved caspase-3 from the ex vivo in tumor culture. These studies, for the first time, demonstrate that a non-toxic hydrophilic lysinated derivative of betulonic acid and its solubility in a biocompatible aqueous medium has enhanced the bioavailability of the drug and has thus unleashed its full anti-prostate cancer activity.


Assuntos
Antineoplásicos/farmacologia , Lisina/química , Ácido Oleanólico/análogos & derivados , Neoplasias da Próstata/tratamento farmacológico , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Caspase 3 , Caspases/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Interações Hidrofóbicas e Hidrofílicas , Imuno-Histoquímica , Técnicas In Vitro , Lisina/análogos & derivados , Masculino , Camundongos , Camundongos Nus , Mitose/efeitos dos fármacos , Conformação Molecular , Ácido Oleanólico/síntese química , Ácido Oleanólico/química , Ácido Oleanólico/farmacologia , Neoplasias da Próstata/patologia , Solubilidade , Estereoisomerismo , Relação Estrutura-Atividade , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
5.
J Reprod Immunol ; 63(2): 123-35, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15380943

RESUMO

Human lutropin (hLH) and human chorionic gonadotropin (hCG) are structurally and functionally similar and play important roles in reproduction via a common gonadal receptor (LH-R). However, hormone specific hCG-beta subunit contains 24 additional amino acid carboxyl terminal peptide (CTP), which produce specific antibodies to hCG-beta with little cross-reaction with LH. A chimeric protein containing both hLH-R and hCG-beta would provide a unique bifunctional antigen for immunocontraception. In this study is described the synthesis of a chimeric DNA construct of full-length of hLH-receptor and hCG-beta and its expression in Sf9 cells to produce a bifunctional protein. Recombinant protein was recognized by antibodies to LH-R as well as anti-hCG-beta in Western Blots, thus indicating the preservation of immunological epitopes for both hLH-R and hCG-beta in the chimera. Specific ligand binding of recombinant hLH-R component was demonstrated by the displacement of bound labeled hCG at increasing concentrations of unlabeled hCG, indicating that, the presence of hCG-beta component of the chimera did not interfere with the binding of hCG to LH-R. hCG-beta was also present in the recombinant chimeric protein as shown by a specific hCG-beta chemiluminescence assay. Treatment of transfected Sf9 cells with hCG induced dose-dependent increase in the stimulation of intracellular cAMP production, which showed that the ligand binding had functional activity. These results demonstrate that the chimeric DNA construct of hLHR-hCG-beta expressed a bifunctional protein containing both hLH-R and hCG-beta activities, which could provide a unique potential antigen for immunocontraception in vertebrates.


Assuntos
Gonadotropina Coriônica Humana Subunidade beta/metabolismo , Receptores do LH/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Animais , Linhagem Celular , Gonadotropina Coriônica Humana Subunidade beta/genética , AMP Cíclico/metabolismo , Expressão Gênica , Vetores Genéticos , Humanos , Receptores do LH/genética , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética
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