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1.
Hum Mutat ; 43(7): 869-876, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35332613

RESUMO

Heterozygosity for missense variants and small in-frame deletions in GARS1 has been reported in patients with a range of genetic neuropathies including Charcot-Marie-Tooth disease type 2D (CMT2D), distal hereditary motor neuropathy type V (dHMN-V), and infantile spinal muscular atrophy (iSMA). We identified two unrelated patients who are each heterozygous for a previously unreported missense variant modifying amino-acid position 336 in the catalytic domain of GARS1. One patient was a 20-year-old woman with iSMA, and the second was a 41-year-old man with CMT2D. Functional studies using yeast complementation assays support a loss-of-function effect for both variants; however, this did not reveal variable effects that might explain the phenotypic differences. These cases expand the mutational spectrum of GARS1-related disorders and demonstrate phenotypic variability based on the specific substitution at a single residue.


Assuntos
Doença de Charcot-Marie-Tooth , Glicina-tRNA Ligase , Humanos , Doença de Charcot-Marie-Tooth/genética , Códon , Glicina-tRNA Ligase/genética , Mutação , Fenótipo
2.
Hum Mutat ; 41(3): 591-599, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31821646

RESUMO

RHOA is a member of the Rho family of GTPases that are involved in fundamental cellular processes including cell adhesion, migration, and proliferation. RHOA can stimulate the formation of stress fibers and focal adhesions and is a key regulator of actomyosin dynamics in various tissues. In a Genematcher-facilitated collaboration, we were able to identify four unrelated individuals with a specific phenotype characterized by hypopigmented areas of the skin, dental anomalies, body asymmetry, and limb length discrepancy due to hemihypotrophy of one half of the body, as well as brain magnetic resonance imaging (MRI) anomalies. Using whole-exome and ultra-deep amplicon sequencing and comparing genomic data of affected and unaffected areas of the skin, we discovered that all four individuals carried the identical RHOA missense variant, c.139G>A; p.Glu47Lys, in a postzygotic state. Molecular modeling and in silico analysis of the affected p.Glu47Lys residue in RHOA indicated that this exchange is predicted to specifically alter the interaction of RHOA with its downstream effectors containing a PKN-type binding domain and thereby disrupts its ability to activate signaling. Our findings indicate that the recurrent postzygotic RHOA missense variant p.Glu47Lys causes a specific mosaic disorder in humans.


Assuntos
Alelos , Códon , Estudos de Associação Genética , Variação Genética , Placa Neural/metabolismo , Fenótipo , Proteína rhoA de Ligação ao GTP/genética , Adolescente , Adulto , Encéfalo/anormalidades , Encéfalo/diagnóstico por imagem , Criança , Pré-Escolar , Feminino , Humanos , Imageamento por Ressonância Magnética , Modelos Moleculares , Placa Neural/anormalidades , Placa Neural/embriologia , Conformação Proteica , Relação Estrutura-Atividade , Adulto Jovem , Proteína rhoA de Ligação ao GTP/química
3.
RNA ; 24(1): 12-17, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29042507

RESUMO

Foot-and-mouth disease virus (FMDV) has a positive-sense ssRNA genome including a single, large, open reading frame. Splitting of the encoded polyprotein at the 2A/2B junction is mediated by the 2A peptide (18 residues long), which induces a nonproteolytic, cotranslational "cleavage" at its own C terminus. A conserved feature among variants of 2A is the C-terminal motif N16P17G18/P19, where P19 is the first residue of 2B. It has been shown previously that certain amino acid substitutions can be tolerated at residues E14, S15, and N16 within the 2A sequence of infectious FMDVs, but no variants at residues P17, G18, or P19 have been identified. In this study, using highly degenerate primers, we analyzed if any other residues can be present at each position of the NPG/P motif within infectious FMDV. No alternative forms of this motif were found to be encoded by rescued FMDVs after two, three, or four passages. However, surprisingly, a clear codon preference for the wt nucleotide sequence encoding the NPGP motif within these viruses was observed. Indeed, the codons selected to code for P17 and P19 within this motif were distinct; thus the synonymous codons are not equivalent.


Assuntos
Vírus da Febre Aftosa/química , Proteínas Virais/química , Sequência de Aminoácidos , Substituição de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Códon , Cricetinae , Vírus da Febre Aftosa/genética , Proteínas Virais/genética
4.
J Virol ; 93(13)2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-30996087

RESUMO

Enterovirus A71 (EV-A71) is a major pathogen that causes hand-foot-and-mouth disease (HFMD), which occasionally results in severe neurological complications. In this study, we developed four EV-A71 (rgEV-A71) strains by reverse genetics procedures as possible vaccine candidates. The four rgEV-A71 viruses contained various codon-deoptimized VP1 capsid proteins (VP1-CD) and showed replication rates and antigenicity similar to that of the wild-type virus, while a fifth virus, rg4643C4VP-CD, was unable to form plaques but was still able to be examined by median tissue culture infectious dose (TCID50) titers, which were similar to those of the others, indicating the effect of CD on plaque formation. However, the genome stability showed that there were some mutations which appeared during just one passage of the VP1-CD viruses. Thus, we further constructed VP1-CD rgEV-A71 containing high-fidelity determinants in 3D polymerase (CD-HF), and the number of mutations in CD-HF rgEV-A71 was shown to have decreased. The CD-HF viruses showed less virulence than the parental strain in a mouse infection model. After 14 days postimmunization, antibody titers had increased in mice infected with CD-HF viruses. The mouse antisera showed similar neutralizing antibody titers against various CD-HF viruses and different genotypes of EV-A71. The study demonstrates the proof of concept that VP1 codon deoptimization combined with high-fidelity 3D polymerase decreased EV-A71 mutations and virulence in mice but retained their antigenicity, indicating it is a good candidate for next-generation EV-A71 vaccine development.IMPORTANCE EV-A71 can cause severe neurological diseases with fatality in infants and young children, but there are still no effective drugs to date. Here, we developed a novel vaccine strategy with the combination of CD and HF substitutions to generate the genetically stable reverse genetics virus. We found that CD combined with HF polymerase decreased the virulence but maintained the antigenicity of the virus. This work demonstrated the simultaneous introduction of CD genome sequences and HF substitutions as a potential new strategy to develop attenuated vaccine seed virus. Our work provides insight into the development of a low-virulence candidate vaccine virus through a series of genetic editing of virus sequences while maintaining its antigenicity and genome stability, which will provide an additional strategy for next-generation vaccine development of EV-A71.


Assuntos
Proteínas do Capsídeo/imunologia , Códon , Infecções por Enterovirus/imunologia , Infecções por Enterovirus/prevenção & controle , Enterovirus/imunologia , Imunogenicidade da Vacina/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes , Antígenos Virais/genética , Antígenos Virais/imunologia , Sequência de Bases , Proteínas do Capsídeo/genética , Enterovirus/genética , Enterovirus/crescimento & desenvolvimento , Enterovirus Humano A/genética , Enterovirus Humano A/imunologia , Infecções por Enterovirus/virologia , Instabilidade Genômica , Doença de Mão, Pé e Boca/imunologia , Doença de Mão, Pé e Boca/prevenção & controle , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Mutação , Virulência , Replicação Viral
5.
BMC Evol Biol ; 19(1): 31, 2019 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-30674270

RESUMO

BACKGROUND: The gene for odontogenic ameloblast-associated (ODAM) is a member of the secretory calcium-binding phosphoprotein gene family. ODAM is primarily expressed in dental tissues including the enamel organ and the junctional epithelium, and may also have pleiotropic functions that are unrelated to teeth. Here, we leverage the power of natural selection to test competing hypotheses that ODAM is tooth-specific versus pleiotropic. Specifically, we compiled and screened complete protein-coding sequences, plus sequences for flanking intronic regions, for ODAM in 165 placental mammals to determine if this gene contains inactivating mutations in lineages that either lack teeth (baleen whales, pangolins, anteaters) or lack enamel on their teeth (aardvarks, sloths, armadillos), as would be expected if the only essential functions of ODAM are related to tooth development and the adhesion of the gingival junctional epithelium to the enamel tooth surface. RESULTS: We discovered inactivating mutations in all species of placental mammals that either lack teeth or lack enamel on their teeth. A surprising result is that ODAM is also inactivated in a few additional lineages including all toothed whales that were examined. We hypothesize that ODAM inactivation is related to the simplified outer enamel surface of toothed whales. An alternate hypothesis is that ODAM inactivation in toothed whales may be related to altered antimicrobial functions of the junctional epithelium in aquatic habitats. Selection analyses on ODAM sequences revealed that the composite dN/dS value for pseudogenic branches is close to 1.0 as expected for a neutrally evolving pseudogene. DN/dS values on transitional branches were used to estimate ODAM inactivation times. In the case of pangolins, ODAM was inactivated ~ 65 million years ago, which is older than the oldest pangolin fossil (Eomanis, 47 Ma) and suggests an even more ancient loss or simplification of teeth in this lineage. CONCLUSION: Our results validate the hypothesis that the only essential functions of ODAM that are maintained by natural selection are related to tooth development and/or the maintenance of a healthy junctional epithelium that attaches to the enamel surface of teeth.


Assuntos
Ameloblastos/metabolismo , Esmalte Dentário/metabolismo , Eutérios/genética , Inativação Gênica , Odontogênese , Proteínas/genética , Baleias/genética , Animais , Sequência de Bases , Teorema de Bayes , Códon/genética , Feminino , Fósseis , Funções Verossimilhança , Mutação/genética , Filogenia , Gravidez , Proteínas/metabolismo
6.
Appl Microbiol Biotechnol ; 103(2): 833-842, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30421111

RESUMO

Porcine circovirus type 2 (PCV2) is a ubiquitous virus with high pathogenicity closely associated with the postweaning multisystemic wasting syndrome (PMWS) and porcine circovirus diseases (PCVDs), which caused significant economic losses in the swine industry worldwide every year. The PCV2 virus-like particles (VLPs) are a powerful subunit vaccine that can elicit high immune response due to its native PCV2 virus morphology. The baculovirus expression system is the widely used platform for producing commercial PCV2 VLP vaccines, but its yield and cost limited the development of low-cost vaccines for veterinary applications. Here, we applied a nonconventional yeast Kluyveromyces marxianus to enhance the production of PCV2 VLPs. After codon optimization, the PCV2 Cap protein was expressed in K. marxianus and assemble spontaneously into VLPs. Using a chemically defined medium, we achieved approximately 1.91 g/L of PCV2 VLP antigen in a 5-L bioreactor after high cell density fermentation for 72 h. That yield greatly exceeded to recently reported PCV2 VLPs obtained by baculovirus-insect cell, Escherichia coli and Pichia pastoris. By the means of two-step chromatography, 652.8 mg of PCV2 VLP antigen was obtained from 1 L of the recombinant K. marxianus cell culture. The PCV2 VLPs induced high level of anti-PCV2 IgG antibody in mice serums and decreased the virus titers in both livers and spleens of the challenged mice. These results illustrated that K. marxianus is a powerful yeast for cost-effective production of PCV2 VLP vaccines.


Assuntos
Infecções por Circoviridae/prevenção & controle , Circovirus/metabolismo , Kluyveromyces/metabolismo , Vacinas de Partículas Semelhantes a Vírus/imunologia , Proteínas Virais/metabolismo , Virossomos/metabolismo , Animais , Anticorpos Antivirais/sangue , Reatores Biológicos , Cromatografia , Infecções por Circoviridae/patologia , Infecções por Circoviridae/virologia , Circovirus/genética , Códon , Meios de Cultura/química , Modelos Animais de Doenças , Kluyveromyces/genética , Fígado/virologia , Camundongos , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Baço/virologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/isolamento & purificação , Vacinas de Partículas Semelhantes a Vírus/administração & dosagem , Vacinas de Partículas Semelhantes a Vírus/isolamento & purificação , Proteínas Virais/genética , Proteínas Virais/isolamento & purificação , Virossomos/genética
7.
Genomics ; 110(6): 382-388, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29262306

RESUMO

Herein, the complete mitochondrial genome of Odontobutis haifengensis was sequenced for the first time. The O. haifengensis mitogenome was 17,016bp in length and included 13 protein-coding genes, 22 transfer RNAs (tRNAs), 2 ribosomal RNAs (rRNAs), and a control region (CR). The genome organization, base composition, codon usage, and gene rearrangement was similar to other Odontobutis species. Furthermore, a tRNA gene rearrangement within the SLH cluster was found to be identical to other Odontobutis species. Moreover, the gene order and the positions of additional intergenic non-coding regions suggests that the observed unique gene rearrangement resulted from a tandem duplication and random loss of large-scale gene regions. Additionally, phylogenetic analysis showed that Odontobutis species form a monophyletic clade due to the conserved mitochondrial gene rearrangement. This study provides useful information that aids in a better understanding of mitogenomic diversity and evolutionary patterns of Odontobutidae species.


Assuntos
Rearranjo Gênico , Genoma Mitocondrial , Perciformes/genética , Filogenia , Animais , Composição de Bases , Códon , Análise de Sequência de DNA
8.
Prep Biochem Biotechnol ; 49(4): 368-374, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30734630

RESUMO

The emergence of drug resistance in Streptococcus pneumoniae (Spn) is a global health threat and necessitates discovery of novel therapeutics. The serine acetyltransferase (also known as CysE) is an enzyme of cysteine biosynthesis pathway and is reported to be essential for the survival of several pathogenic bacteria. Therefore, it appears to be a very attractive target for structure-function understanding and inhibitor design. This study describes the molecular cloning of cysE from Spn in the pET21c vector and efforts carried out for expression and purification of active recombinant CysE. Significant expression of recombinant Spn cysE could be achieved in codon optimized BL21(DE3)-RIL strain as opposed to conventional BL21(DE3) strain. Analysis of codon adaptation index (CAI) with levels of eukaryotic genes and prokaryotic cysEs expressed in heterologous E. coli host suggests that codon optimized E. coli BL21(DE3)-RIL may be a better host for expressing genes with low CAI. Here, an efficient protocol has been developed for recovery of recombinant Spn CysE in soluble and biologically active form by the usage of nonionic detergent Triton X-100 at a concentration as low as 1%. Altogether, this study reports a simple strategy for producing functionally active Spn CysE in E. coli.


Assuntos
Clonagem Molecular/métodos , Serina O-Acetiltransferase/biossíntese , Streptococcus pneumoniae/enzimologia , Sequência de Bases , Códon , Detergentes/química , Escherichia coli/genética , Octoxinol/química , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Serina O-Acetiltransferase/química , Serina O-Acetiltransferase/genética , Serina O-Acetiltransferase/isolamento & purificação
9.
FEMS Yeast Res ; 18(8)2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30107496

RESUMO

As a traditional ethanol-producing microorganism, Saccharomyces cerevisiae is an ideal host for consolidated bioprocessing. However, expression of heterologous cellulase increases the metabolic burden in yeast, which results in low cellulase activity and poor cellulose degradation efficiency. In this study, cellulase-expressing yeast strains that could efficiently degrade different cellulosic substrates were created by optimizing cellulase ratios through a POT1-mediated δ-integration strategy. Metabolic engineering strategies, including optimization of codon usage, promoter and signal peptide, were also included in this system. We also confirmed that heterologous cellulase expression in cellulosic yeast induced the unfolded protein response. To enhance protein folding capacity, the endoplasmic reticulum chaperone protein BiP and the disulfide isomerase Pdi1p were overexpressed, and the Golgi membrane protein Ca2+/Mn2+ ATPase Pmr1p was disrupted to decrease the glycosylation of cellulase. The resultant strain, SK18-3, could produce 5.4 g L-1 ethanol with carboxymethyl-cellulose. Strain SK12-50 achieved 4.7 g L-1 ethanol production with phosphoric acid swollen cellulose hydrolysis. When Avicel was used as the substrate, 3.8 g L-1 ethanol (75% of the theoretical maximum yield) was produced in SK13-34. This work will significantly increase our knowledge of how to engineer optimal yeast strains for biofuel production from cellulosic biomass.


Assuntos
Celulase/genética , Celulase/metabolismo , Celulose/metabolismo , Etanol/metabolismo , Engenharia Metabólica/métodos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Códon , Expressão Gênica , Regiões Promotoras Genéticas , Sinais Direcionadores de Proteínas , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
10.
Biochem Biophys Res Commun ; 482(4): 700-705, 2017 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-27865834

RESUMO

The malaria parasite Plasmodium falciparum requires the Plasmodium translocon of exported proteins (PTEX) to proliferate in human red blood cells. During the blood stages of malaria, several hundred parasite-encoded proteins are exported from the parasite into the cytosol of red blood cells. PTEX is the translocon for protein export and comprises 5 proteins: EXP2, PTEX150, PTEX88, Hsp101 and TRX2. Among them, EXP2 is thought to constitute the transmembrane pore, whereas the other components seem to play a role in unfolding the luggage proteins or providing a driving force. However, detailed functional and structural characterizations of PTEX proteins have not been performed. In this study, we expressed and characterized the membrane-associated component EXP2. Because expression of EXP2 is lethal to E. coli, EXP2 was expressed as a fusion protein with GST, and the recombinant EXP2 was obtained by protease digestion. The recombinant EXP2 formed pores in bilayer lipid membranes. The inner diameter of the pore was estimated to be approximately 3.5 nm based on electron microscopy images and channel currents. From this size and the molecular mass as determined by size exclusion chromatography and blue native polyacrylamide gel electrophoresis, we determined that the pore comprises approximately 10-12 EXP2 subunits. However, there is a possibility that the pore structure is different in the PTEX complex. These results provide important insights in the protein transport mechanism of PTEX, which will aid in developing new drugs targeting PTEX.


Assuntos
Membrana Celular/metabolismo , Eritrócitos/parasitologia , Proteínas de Membrana/metabolismo , Plasmodium falciparum/metabolismo , Proteínas de Protozoários/metabolismo , Proteínas Recombinantes/metabolismo , Códon , Escherichia coli/metabolismo , Hemólise , Humanos , Bicamadas Lipídicas/química , Lipossomos/química , Microscopia Eletrônica de Transmissão , Conformação Proteica , Transporte Proteico
11.
Cytogenet Genome Res ; 152(3): 111-116, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28877528

RESUMO

We described a 5-year-old male with hypodontia, hypohidrosis, and facial dysmorphisms characterized by a depressed nasal bridge, maxillary hypoplasia, and protuberant lips. Chromosomal analysis revealed a normal 46,XY male karyotype. Due to the presence of clinical features of hypohidrotic ectodermal dysplasia (HED), the EDA gene, located at Xq12q13.1, of the patient and his family was sequenced. Analysis of the proband's sequence revealed a missense mutation (T to A transversion) in hemizygosity state at nucleotide position 158 in exon 1 of the EDA gene, which changes codon 53 from leucine to histidine, while heterozygosity at this position was detected in the slightly affected mother; moreover, this mutation was not found in the publically available Human Gene Mutation Database. To date, our findings indicate that a novel mutation in EDA is associated with X-linked HED, adding it to the repertoire of EDA mutations.


Assuntos
Displasia Ectodérmica Anidrótica Tipo 1/genética , Ectodisplasinas/genética , Mutação de Sentido Incorreto , Substituição de Aminoácidos , Anodontia/genética , Anodontia/patologia , Pré-Escolar , Códon , Análise Mutacional de DNA , Displasia Ectodérmica Anidrótica Tipo 1/patologia , Feminino , Genes Ligados ao Cromossomo X , Hemizigoto , Heterozigoto , Histidina/genética , Humanos , Hipo-Hidrose/genética , Hipo-Hidrose/patologia , Leucina/genética , Lábio/anormalidades , Masculino , Maxila/anormalidades , Osso Nasal/anormalidades
12.
Arch Microbiol ; 199(4): 605-611, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28138738

RESUMO

Bioethanol is one of the main biofuels produced from the fermentation of saccharified agricultural waste; however, this technology needs to be optimized for profitability. Because the commonly used ethanologenic yeast strains are unable to assimilate cellobiose, several efforts have been made to express cellulose hydrolytic enzymes in these yeasts to produce ethanol from lignocellulose. The C. flavigenabglA gene encoding ß-glucosidase catalytic subunit was optimized for preferential codon usage in S. cerevisiae. The optimized gene, cloned into the episomal vector pRGP-1, was expressed, which led to the secretion of an active ß-glucosidase in transformants of the S. cerevisiae diploid strain 2-24D. The volumetric and specific extracellular enzymatic activities using pNPG as substrate were 155 IU L-1 and 222 IU g-1, respectively, as detected in the supernatant of the cultures of the S. cerevisiae RP2-BGL transformant strain growing in cellobiose (20 g L-1) as the sole carbon source for 48 h. Ethanol production was 5 g L-1 after 96 h of culture, which represented a yield of 0.41 g g-1 of substrate consumed (12 g L-1), equivalent to 76% of the theoretical yield. The S. cerevisiae RP2-BGL strain expressed the ß-glucosidase extracellularly and produced ethanol from cellobiose, which makes this microorganism suitable for application in ethanol production processes with saccharified lignocellulose.


Assuntos
Biocombustíveis , Celobiose/metabolismo , Cellulomonas/enzimologia , Etanol/metabolismo , Saccharomyces cerevisiae/genética , beta-Glucosidase/genética , Celulose/metabolismo , Códon , Lignina/metabolismo , Saccharomyces cerevisiae/metabolismo , beta-Glucosidase/metabolismo
13.
Appl Microbiol Biotechnol ; 101(10): 4227-4245, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28238082

RESUMO

Chlamydomonas reinhardtii offers a great promise for large-scale production of multiple recombinant proteins of pharmaceutical and industrial interest. However, the nuclear-encoding transgenes usually are expressed at a low level, which severely hampers the use of this alga in molecular farming. In this study, the promoter of the endogenous intraflagellar transport 25 (IFT25) gene of C. reinhardtii was tested for its ability to drive the expression of green fluorescent protein (GFP), which functions as a readout for target gene expression. IFT25 promoter (IFT25P) alone was not able to drive GFP expression to a detectable level. IFT25P, however, can drive robust IFT25-GFP fusion protein expression when the intron-containing IFT25 gene was inserted between IFT25P and GFP cDNA. When an extended version of foot-and-mouth virus 2A protease (2AE) sequence was further inserted between the intron-containing IFT25 gene and the GFP cDNA, discrete GFP protein was observed to release from the IFT25-2AE-GFP polyprotein via 2A self-cleaving with a cleavage efficacy of approximately 99%. The monomer GFP was accumulated to a level of as high as 0.68% of total soluble proteins. To test whether the newly developed bicistronic IFT25P-IFT25-2AE expression system can be used to overexpress heterologous proteins of different origins and sizes, we inserted codon-optimized cDNAs encoding a Trichoderma reesei xylanase1 (25 kDa) and a Lachnospiraceae bacterium ND2006 type V CRISPR-Cas protein LbCpf1 (147 kDa) to the vector and found that the production of xylanase1 and LbCpf1 was as high as 0.69 and 0.49% of total soluble protein. Our result showed that IFT25P-IFT25-2AE system is more efficient to drive nuclear gene expression in C. reinhardtii than other conventionally used promoters, thus representing a novel efficient recombinant protein expression tool and has the potential to be scaled for commercial production of nuclear-encoded recombinant proteins of different sizes and origins in C. reinhardtii.


Assuntos
Chlamydomonas reinhardtii/genética , Expressão Gênica , Transgenes , Proteínas Virais/genética , Reatores Biológicos , Códon , DNA Complementar , Proteínas de Fluorescência Verde/genética , Proteínas Luminescentes/genética , Regiões Promotoras Genéticas , Proteínas Recombinantes de Fusão/biossíntese
14.
Plant Cell Physiol ; 57(4): 824-47, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26872835

RESUMO

The MYB superfamily is large and functionally diverse in plants. To date, MYB family genes have not yet been identified in Chinese white pear (Pyrus bretschneideri), and their functions remain unclear. In this study, we identified 231 genes as candidate MYB genes and divided them into four subfamilies. The R2R3-MYB (PbrMYB) family shared an R2R3 domain with 104 amino acid residues, including five conserved tryptophan residues. The Pbr MYB family was divided into 37 functional subgroups including 33 subgroups which contained both MYB genes of Rosaceae plants and AtMYB genes, and four subgroups which included only Rosaceae MYB genes or AtMYB genes. PbrMYB genes with similar functions clustered into the same subgroup, indicating functional conservation. We also found that whole-genome duplication (WGD) and dispersed duplications played critical roles in the expansion of the MYB family. The 87 Pbr MYB duplicated gene pairs dated back to the two WGD events. Purifying selection was the primary force driving Pbr MYB gene evolution. The 15 gene pairs presented 1-7 codon sites under positive selection. A total of 147 expressed genes were identified from RNA-sequencing data of fruit, and six Pbr MYB members in subgroup C1 were identified as important candidate genes in the regulation of lignin synthesis by quantitative real-time PCR analysis. Further correlation analysis revealed that six PbrMYBs were significantly correlated with five structural gene families (F5H, HCT, CCR, POD and C3'H) in the lignin pathway. The phylogenetic, evolution and expression analyses of the MYB gene family in Chinese white pear establish a solid foundation for future comprehensive functional analysis of Pbr MYB genes.


Assuntos
Evolução Molecular , Genes de Plantas , Genes myb , Pyrus/genética , Fatores de Transcrição/genética , Sequência de Aminoácidos , Códon , Sequência Conservada , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Lignina/biossíntese , Lignina/genética , Família Multigênica , Filogenia , Proteínas de Plantas/genética , Reação em Cadeia da Polimerase em Tempo Real , Rosaceae/genética , Seleção Genética
15.
Am J Med Genet A ; 170(10): 2698-705, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27312461

RESUMO

Alternating hemiplegia of childhood is an early onset neurodevelopmental disorder characterized by paroxystic episodes of alternating hemiplegia, variable degrees of intellectual disability, and dystonic movements. The main causative gene, ATP1A3, is also responsible for other neurodevelopmental disorders. While the neurological profile of this condition is well defined, the question whether a recognizable pattern of physical anomalies does exist in this condition is still open. We performed a morphological evaluation of 30 patients at different ages. All patients were evaluated independently by each author and evaluation sheets were compared, discussed, and agreed afterwards. This study started before the identification of ATP1A3 as the causative gene, and the patients were selected upon their neurological picture. Four of these 30 patients tested negative for ATP1A3 mutations and were excluded from the present work. On physical ground, almost all patients shared a similar physical phenotype consisting of hypotonia, long face, thin eyebrows, strabismus, hypertelorism, long palpebral fissures, downturned mouth, and slender habitus. Such phenotype is sufficiently typical to generate a recognizable gestalt. We also evaluated patients photographs taken from the parents in early childhood (6-20 months) to delineate a clinical profile possibly recognizable before the neurological signs suggest the diagnosis. Our data suggest that the typical early gestalt is sufficient to advise the molecular analysis of ATP1A3, even in absence of the pathognomonic neurological signs. Finally, since a number of patients is now adult, some information can be drawn on the phenotypic evolution of the facial appearance of patients with alternating hemiplegia of childhood. © 2016 Wiley Periodicals, Inc.


Assuntos
Fácies , Hemiplegia/diagnóstico , Fenótipo , Substituição de Aminoácidos , Pré-Escolar , Códon , Feminino , Hemiplegia/genética , Humanos , Lactente , Recém-Nascido , Masculino , Mutação , Diagnóstico Pré-Natal , ATPase Trocadora de Sódio-Potássio/genética
16.
Virus Genes ; 52(2): 235-43, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26873406

RESUMO

Foot-and-mouth disease virus (FMDV) particles lose infectivity due to their dissociation into pentamers at pH value below 6.5. After the uptake of FMDV by receptor-mediated endocytosis, the acid-dependent dissociation process is required for the release of FMDV genome inside endosomes. Nevertheless, dissociation of FMDV particles in mildly acidic conditions renders the inactivated FMD vaccine less effective. To improve the acid stability of inactivated FMD vaccine during the manufacturing process, a serotype A IND 40/2000 (in-use vaccine strain) mutant with increased resistance to acid inactivation was generated through reverse genetics approach. Based upon the earlier reports, the crucial amino acid residue, H142 of VP3 capsid protein was substituted separately to various amino acid residues Arg (R), Phe (F), Ala (A), and Asp (D) on the full-genome length cDNA clone. While the H142 â†’ R or H142 â†’ F or H142 â†’ A substitutions resulted in non-infectious FMDV, H142 â†’ D mutation on VP3 protein (H3142D) resulted in the generation of mutant virus with enhanced resistance to acid-induced inactivation. In addition, H3142D substitution did not alter the replication ability and antigenicity of mutant as compared to the parental virus. However, the virus competition experiments revealed that the H3142D substitution conferred a loss of fitness for the mutant virus. Results from this study demonstrate that the H3142D substitution is the molecular determinant of acid-resistant phenotype in FMDV serotype A.


Assuntos
Ácidos/farmacologia , Substituição de Aminoácidos , Proteínas do Capsídeo/genética , Códon , Vírus da Febre Aftosa/efeitos dos fármacos , Vírus da Febre Aftosa/genética , Animais , Antígenos Virais/imunologia , Proteínas do Capsídeo/química , Proteínas do Capsídeo/imunologia , Linhagem Celular , Endossomos/virologia , Febre Aftosa/virologia , Vírus da Febre Aftosa/classificação , Aptidão Genética , Concentração de Íons de Hidrogênio , Mutação , Estabilidade Proteica , Sorogrupo , Ativação Viral/efeitos dos fármacos , Replicação Viral
17.
Eur Biophys J ; 44(7): 589-98, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26233759

RESUMO

The mechanosensitive channel of large conductance MscL is a well-characterized mechanically gated non-selective ion channel, which often serves as a prototype mechanosensitive channel for mechanotransduction studies. However, there are some discrepancies between MscL constructs used in these studies, most notably unintended heterogeneous expression from some MscL expression constructs. In this study we investigate the possible cause of this expression pattern, and compare the original non-homogenously expressing constructs with our new homogeneously expressing one to confirm that there is little functional difference between them. In addition, a new MscL construct has been developed with an improved molar extinction coefficient at 280 nm, enabling more accurate protein quantification.


Assuntos
Proteínas de Escherichia coli/metabolismo , Canais Iônicos/metabolismo , Sequência de Aminoácidos , Códon , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Canais Iônicos/química , Canais Iônicos/genética , Lipossomos/metabolismo , Dados de Sequência Molecular , Estrutura Terciária de Proteína
18.
J Oral Maxillofac Surg ; 73(1): 194.e1-9, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25511968

RESUMO

Hyperparathyroidism-jaw tumor (HPT-JT) was first observed by Jackson in 1958 in a family who exhibited hyperparathyroidism and recurrent pancreatitis. The author noticed the presence of jaw tumors in the affected family and reported them as fibrous dysplasia. However, it was not until 1990 that a familial variety of hyperparathyroidism with fibro-osseous jaw tumors was recognized as HPT-JT syndrome and reported as a clinically and genetically distinct syndrome. Hyperparathyroidism generally arises from glandular hyperplasia or parathyroid adenomas, with only about 1% of cases resulting from parathyroid carcinoma. However, parathyroid carcinoma develops in about 15% of HPT-JT patients. The true incidence of HPT-JT is unknown, although the prevalence of about 100 published cases suggests its rarity. Twenty percent of HPT-JT cases have renal hamartomas or tumors, and female patients with HPT-JT have been reported to have carcinoma of the uterus. This syndrome appears to arise from a variety of mutations that deactivate the tumor suppressor gene CDC73 (also known as HRPT2) and its production of the tumor suppressor protein parafibromin. Functional parafibromin has 531 amino acids, and mutations result in a short nonfunctional protein. CDC73 disorders exhibit dominant germline gene behavior, with varying degrees of penetration. In most cases an affected person has 1 parent with the condition, which raises the need for family investigation and genetic counseling. We report a case of HPT-JT syndrome in a male patient who presented to the local community hospital 6 years previously with a history of back pain. Investigations showed elevated serum parathyroid hormone and calcium levels, and a technetium 99m sestamibi parathyroid scan showed increased activity at the site of the lower left gland that proved to be a substernal parathyroid carcinoma. The patient's parathyroid hormone level dropped from 126 to 97 pg/mL at 5 minutes and was 65 pg/mL at 10 minutes after excision of the gland, and the calcium chemistry findings returned to normal. Parathyroid histologic analysis showed substantial cytologic atypia with nuclear pleomorphism and prominent nucleoli, but infrequent mitoses. Although the capsule was described as showing foci of vascular invasion by the carcinoma, there has been no evidence of recurrence. Six years later, the patient presented with bilateral mandibular cemento-ossifying fibromas, but no evidence of hyperparathyroidism. The larger left tumor was excised and immediately reconstructed with an autogenous iliac crest bone graft, and the right lesion was enucleated. There has been no recurrence in 12 months. This case illustrates that the hyperparathyroidism and the fibro-osseous tumors are independent features of the persistent germline tumor suppressor gene (CDC73) mutation. The syndromic fibro-osseous tumors are odontogenic cemento-ossifying fibromas, which only occur in the jaws.


Assuntos
Adenoma/genética , Fibroma/genética , Mutação em Linhagem Germinativa/genética , Hiperparatireoidismo/genética , Neoplasias Maxilomandibulares/genética , Proteínas Supressoras de Tumor/genética , Adulto , Carcinoma/genética , Códon/genética , Códon de Terminação/genética , Fibroma Ossificante/genética , Seguimentos , Deleção de Genes , Humanos , Masculino , Neoplasias Mandibulares/genética , Tumores Odontogênicos/genética , Neoplasias das Paratireoides/genética
19.
Int J Mol Sci ; 16(10): 25031-49, 2015 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-26492246

RESUMO

To understand the molecular evolution of mitochondrial genomes (mitogenomes) in the genus Odontobutis, the mitogenome of Odontobutis yaluensis was sequenced and compared with those of another four Odontobutis species. Our results displayed similar mitogenome features among species in genome organization, base composition, codon usage, and gene rearrangement. The identical gene rearrangement of trnS-trnL-trnH tRNA cluster observed in mitogenomes of these five closely related freshwater sleepers suggests that this unique gene order is conserved within Odontobutis. Additionally, the present gene order and the positions of associated intergenic spacers of these Odontobutis mitogenomes indicate that this unusual gene rearrangement results from tandem duplication and random loss of large-scale gene regions. Moreover, these mitogenomes exhibit a high level of sequence variation, mainly due to the differences of corresponding intergenic sequences in gene rearrangement regions and the heterogeneity of tandem repeats in the control regions. Phylogenetic analyses support Odontobutis species with shared gene rearrangement forming a monophyletic group, and the interspecific phylogenetic relationships are associated with structural differences among their mitogenomes. The present study contributes to understanding the evolutionary patterns of Odontobutidae species.


Assuntos
Ordem dos Genes/genética , Genoma Mitocondrial/genética , Perciformes/genética , Animais , Códon/genética , Evolução Molecular , Variação Genética/genética , Perciformes/classificação , Filogenia , Sequências de Repetição em Tandem/genética
20.
Mol Phylogenet Evol ; 78: 314-23, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24929245

RESUMO

Mitochondrial sequences have long been used to examine vertebrate phylogenetic relationships. The extensive use of mitochondrial data reflects the ease of obtaining mitochondrial sequences and its relatively rapid coalescence time. Mitochondrial genomes typically do not undergo recombination, so the entire mitogenome should have the same underlying gene tree. Thus, given appropriate analyses, conflict among estimates of phylogeny from different mitochondrial regions should not exist. However, estimates of phylogeny based upon different mitochondrial regions can exhibit incongruence. Conflict in phylogenetic signal among mitochondrial regions has been observed in galliform birds for the position of the Odontophoridae (New World quail). To explore this, we expanded sampling to 47 galliform mitogenomes, adding six new mitogenomes, which included representatives of two previously unsampled families. Analyses of complete mitogenomes recovered a well-supported topology that was congruent with expectations from multi-locus studies. However, when analyzing individual regions, we found conflicting positions for the Odontophoridae and several other relationships at multiple taxonomic levels. We tested multiple analytical strategies to reduce incongruence among regions, including partitioning by codon position, using mixture and codon-based models, RY coding, and excluding potentially misleading sites. No approach consistently reduced the conflict among mitochondrial regions at any taxonomic level. The biological attributes of both strongly misleading and non-misleading sites were essentially identical. Increasing taxa actually appeared to increase conflicting signal, even when taxa were selected to break up long branches. Collectively, our results indicate that analyzing mitochondrial data remains difficult, although analyzing complete mitogenomes resulted in a good estimate of the mitochondrial gene tree.


Assuntos
Galliformes/classificação , Genoma Mitocondrial , Filogenia , Animais , Códon , Galliformes/genética , Genes Mitocondriais , Dados de Sequência Molecular , Análise de Sequência de DNA
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