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1.
PLoS One ; 14(12): e0226485, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31869362

RESUMO

Body size reduction, also known as miniaturization, is an important evolutionary process that affects a number of physiological and phenotypic traits and helps animals conquer new ecological niches. However, this process is poorly understood at the molecular level. Here, we report genomic and transcriptomic features of arguably the smallest known insect-the parasitoid wasp, Megaphragma amalphitanum (Hymenoptera: Trichogrammatidae). In contrast to expectations, we find that the genome and transcriptome sizes of this parasitoid wasp are comparable to other members of the Chalcidoidea superfamily. Moreover, compared to other chalcid wasps the gene content of M. amalphitanum is remarkably conserved. Intriguingly, we observed significant changes in M. amalphitanum transposable element dynamics over time, in which an initial burst was followed by suppression of activity, possibly due to a recent reinforcement of the genome defense machinery. Overall, while the M. amalphitanum genomic data reveal certain features that may be linked to the unusual biological properties of this organism, miniaturization is not associated with a large decrease in genome complexity.


Assuntos
Tamanho Corporal/genética , Genoma de Inseto , Vespas/genética , Adaptação Biológica/genética , Animais , Mapeamento Cromossômico , Ecossistema , Evolução Molecular , Genes de Insetos , Especiação Genética , Interações Hospedeiro-Parasita/genética , Sistema Imunitário/metabolismo , Anotação de Sequência Molecular , Análise de Sequência de DNA , Transcriptoma/genética , Peçonhas/genética , Vespas/anatomia & histologia , Vespas/imunologia , Vespas/patogenicidade
2.
J Proteome Res ; 18(12): 4206-4214, 2019 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-31599598

RESUMO

This manuscript collects all the efforts of the Russian Consortium, bottlenecks revealed in the course of the C-HPP realization, and ways of their overcoming. One of the main bottlenecks in the C-HPP is the insufficient sensitivity of proteomic technologies, hampering the detection of low- and ultralow-copy number proteins forming the "dark part" of the human proteome. In the frame of MP-Challenge, to increase proteome coverage we suggest an experimental workflow based on a combination of shotgun technology and selected reaction monitoring with two-dimensional alkaline fractionation. Further, to detect proteins that cannot be identified by such technologies, nanotechnologies such as combined atomic force microscopy with molecular fishing and/or nanowire detection may be useful. These technologies provide a powerful tool for single molecule analysis, by analogy with nanopore sequencing during genome analysis. To systematically analyze the functional features of some proteins (CP50 Challenge), we created a mathematical model that predicts the number of proteins differing in amino acid sequence: proteoforms. According to our data, we should expect about 100 000 different proteoforms in the liver tissue and a little more in the HepG2 cell line. The variety of proteins forming the whole human proteome significantly exceeds these results due to post-translational modifications (PTMs). As PTMs determine the functional specificity of the protein, we propose using a combination of gene-centric transcriptome-proteomic analysis with preliminary fractionation by two-dimensional electrophoresis to identify chemically modified proteoforms. Despite the complexity of the proposed solutions, such integrative approaches could be fruitful for MP50 and CP50 Challenges in the framework of the C-HPP.


Assuntos
Proteínas/análise , Proteoma , Proteômica/métodos , Técnicas Biossensoriais , Eletroforese em Gel Bidimensional , Genoma Humano , Humanos , Microscopia de Força Atômica/métodos , Nanotecnologia/métodos , Processamento de Proteína Pós-Traducional , Proteínas/isolamento & purificação , Federação Russa , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Fluxo de Trabalho
3.
Int J Mol Sci ; 20(17)2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31443555

RESUMO

Carnivorous plants have the ability to capture and digest small animals as a source of additional nutrients, which allows them to grow in nutrient-poor habitats. Here we report the complete sequences of the plastid genomes of two carnivorous plants of the order Caryophyllales, Drosera rotundifolia and Nepenthes × ventrata. The plastome of D. rotundifolia is repeat-rich and highly rearranged. It lacks NAD(P)H dehydrogenase genes, as well as ycf1 and ycf2 genes, and three essential tRNA genes. Intron losses are observed in some protein-coding and tRNA genes along with a pronounced reduction of RNA editing sites. Only six editing sites were identified by RNA-seq in D. rotundifolia plastid genome and at most conserved editing sites the conserved amino acids are already encoded at the DNA level. In contrast, the N. × ventrata plastome has a typical structure and gene content, except for pseudogenization of the ccsA gene. N. × ventrata and D. rotundifolia could represent different stages of evolution of the plastid genomes of carnivorous plants, resembling events observed in parasitic plants in the course of the switch from autotrophy to a heterotrophic lifestyle.


Assuntos
Evolução Biológica , Drosera/genética , Genomas de Plastídeos , Genômica , Biologia Computacional/métodos , Drosera/parasitologia , Duplicação Gênica , Rearranjo Gênico , Genes de Plantas , Genômica/métodos , Edição de RNA
4.
PLoS One ; 14(7): e0219434, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31276557

RESUMO

Recombinant human follicle stimulating hormone (FSH), produced in Chinese hamster ovary (CHO) cells, is widely used for treatment of fertility disorders and is subject to biosimilars development. Cell lines with high specific productivities may simplify the FSH production process. Here, we used our previously established expression system based on vector p1.1 to create new cell lines secreting heterodimeric FSH protein. To this end, we linked open reading frames of both FSH subunits by the wild-type internal ribosome entry site from the encephalomyocarditis virus (EMCV IRES). Intact and double-negative for the dihydrofolate reductase CHO cells were stably transfected by the FSH-coding plasmids. Stably transfected intact cells showed higher level of the FSH secretion and were utilized for subsequent methotrexate-driven transgene amplification, which doubled their productivity. The excess of the free α-subunit was corrected by transfecting the cells by the additional p1.1-based plasmid encoding the ß-subunit of the FSH. Clonal cell lines obtained secreted mostly the heterodimeric FSH and possessed specific productivities up to 12.3±1.7 pg/cell/day. Candidate clonal cell line C-P1.3-FSH-G4 maintained a constant specific productivity for at least 2 months of culturing without the section pressure. The resulting FSH protein conformed to the international pharmaceutical quality criteria as evidenced by the receptor binding kinetics, distribution pattern of hormone isoforms and biological activity. In conclusion, our expression system offers a simple and cost-effective approach to production of FSH.


Assuntos
Hormônio Foliculoestimulante Humano/genética , Hormônio Foliculoestimulante Humano/metabolismo , Expressão Gênica , Vetores Genéticos/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Animais , Células CHO , Linhagem Celular , Cricetulus , Ensaio de Imunoadsorção Enzimática , Ordem dos Genes , Humanos , Hibridização in Situ Fluorescente , Plasmídeos/genética , Reação em Cadeia da Polimerase , Polissacarídeos , Sensibilidade e Especificidade
5.
Eur J Hum Genet ; 27(10): 1589-1598, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31231134

RESUMO

Renal cell carcinoma (RCC) has an undisputed genetic component and a stable 2:1 male to female sex ratio in its incidence across populations, suggesting possible sexual dimorphism in its genetic susceptibility. We conducted the first sex-specific genome-wide association analysis of RCC for men (3227 cases, 4916 controls) and women (1992 cases, 3095 controls) of European ancestry from two RCC genome-wide scans and replicated the top findings using an additional series of men (2261 cases, 5852 controls) and women (1399 cases, 1575 controls) from two independent cohorts of European origin. Our study confirmed sex-specific associations for two known RCC risk loci at 14q24.2 (DPF3) and 2p21(EPAS1). We also identified two additional suggestive male-specific loci at 6q24.3 (SAMD5, male odds ratio (ORmale) = 0.83 [95% CI = 0.78-0.89], Pmale = 1.71 × 10-8 compared with female odds ratio (ORfemale) = 0.98 [95% CI = 0.90-1.07], Pfemale = 0.68) and 12q23.3 (intergenic, ORmale = 0.75 [95% CI = 0.68-0.83], Pmale = 1.59 × 10-8 compared with ORfemale = 0.93 [95% CI = 0.82-1.06], Pfemale = 0.21) that attained genome-wide significance in the joint meta-analysis. Herein, we provide evidence of sex-specific associations in RCC genetic susceptibility and advocate the necessity of larger genetic and genomic studies to unravel the endogenous causes of sex bias in sexually dimorphic traits and diseases like RCC.


Assuntos
Carcinoma de Células Renais/epidemiologia , Carcinoma de Células Renais/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Neoplasias Renais/epidemiologia , Neoplasias Renais/genética , Biologia Computacional , Feminino , Humanos , Masculino , Razão de Chances , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Fatores Sexuais
6.
BMC Genomics ; 20(1): 399, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31117933

RESUMO

BACKGROUND: The three epidemiologically important Opisthorchiidae liver flukes Opisthorchis felineus, O. viverrini, and Clonorchis sinensis, are believed to harbour similar potencies to provoke hepatobiliary diseases in their definitive hosts, although their populations have substantially different ecogeographical aspects including habitat, preferred hosts, population structure. Lack of O. felineus genomic data is an obstacle to the development of comparative molecular biological approaches necessary to obtain new knowledge about the biology of Opisthorchiidae trematodes, to identify essential pathways linked to parasite-host interaction, to predict genes that contribute to liver fluke pathogenesis and for the effective prevention and control of the disease. RESULTS: Here we present the first draft genome assembly of O. felineus and its gene repertoire accompanied by a comparative analysis with that of O. viverrini and Clonorchis sinensis. We observed both noticeably high heterozygosity of the sequenced individual and substantial genetic diversity in a pooled sample. This indicates that potency of O. felineus population for rapid adaptive response to control and preventive measures of opisthorchiasis is higher than in O. viverrini and C. sinensis. We also have found that all three species are characterized by more intensive involvement of trans-splicing in RNA processing compared to other trematodes. CONCLUSION: All revealed peculiarities of structural organization of genomes are of extreme importance for a proper description of genes and their products in these parasitic species. This should be taken into account both in academic and applied research of epidemiologically important liver flukes. Further comparative genomics studies of liver flukes and non-carcinogenic flatworms allow for generation of well-grounded hypotheses on the mechanisms underlying development of cholangiocarcinoma associated with opisthorchiasis and clonorchiasis as well as species-specific mechanisms of these diseases.


Assuntos
Cricetinae/parasitologia , Cyprinidae/parasitologia , Genoma Helmíntico , Genômica/métodos , Proteínas de Helminto/genética , Opistorquíase/epidemiologia , Opisthorchis/genética , Sequência de Aminoácidos , Animais , Clonorquíase/epidemiologia , Clonorquíase/genética , Clonorquíase/parasitologia , Clonorchis sinensis/genética , Opistorquíase/genética , Opistorquíase/parasitologia , Homologia de Sequência
7.
Int J Syst Evol Microbiol ; 69(7): 1953-1959, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31038447

RESUMO

Strain LBB-42T was isolated from sediment sampled at Lake Beloe Bordukovskoe, located in the Moscow region (Russia). Phylogenetic analyses based on 16S rRNA gene sequencing results assigned the strain to the genus Magnetospirillum. Major fatty acids were C16 : 1ω7c, C16 : 0 and C18 : 1 ω9/C18 : 1 ω7. Genome sequencing revealed a genome size of 4.40 Mbp and a G+C content of 63.4 mol%. The average nucleotide identity and digital DNA-DNA hybridization values suggested that strain LBB-42T represents a new species, for which we propose the name Magnetospirillum kuznetsovii sp. nov., with the type strain LBB-42T (=VKM B-3270T=KCTC 15749T).


Assuntos
Lagos/microbiologia , Magnetospirillum/classificação , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Magnetospirillum/isolamento & purificação , Moscou , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Federação Russa , Análise de Sequência de DNA
8.
PLoS Med ; 16(1): e1002724, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30605491

RESUMO

BACKGROUND: Several obesity-related factors have been associated with renal cell carcinoma (RCC), but it is unclear which individual factors directly influence risk. We addressed this question using genetic markers as proxies for putative risk factors and evaluated their relation to RCC risk in a mendelian randomization (MR) framework. This methodology limits bias due to confounding and is not affected by reverse causation. METHODS AND FINDINGS: Genetic markers associated with obesity measures, blood pressure, lipids, type 2 diabetes, insulin, and glucose were initially identified as instrumental variables, and their association with RCC risk was subsequently evaluated in a genome-wide association study (GWAS) of 10,784 RCC patients and 20,406 control participants in a 2-sample MR framework. The effect on RCC risk was estimated by calculating odds ratios (ORSD) for a standard deviation (SD) increment in each risk factor. The MR analysis indicated that higher body mass index increases the risk of RCC (ORSD: 1.56, 95% confidence interval [CI] 1.44-1.70), with comparable results for waist-to-hip ratio (ORSD: 1.63, 95% CI 1.40-1.90) and body fat percentage (ORSD: 1.66, 95% CI 1.44-1.90). This analysis further indicated that higher fasting insulin (ORSD: 1.82, 95% CI 1.30-2.55) and diastolic blood pressure (DBP; ORSD: 1.28, 95% CI 1.11-1.47), but not systolic blood pressure (ORSD: 0.98, 95% CI 0.84-1.14), increase the risk for RCC. No association with RCC risk was seen for lipids, overall type 2 diabetes, or fasting glucose. CONCLUSIONS: This study provides novel evidence for an etiological role of insulin in RCC, as well as confirmatory evidence that obesity and DBP influence RCC risk.


Assuntos
Carcinoma de Células Renais/etiologia , Neoplasias Renais/etiologia , Obesidade/complicações , Glicemia/análise , Pressão Sanguínea , Índice de Massa Corporal , Carcinoma de Células Renais/genética , Diabetes Mellitus Tipo 2/complicações , Feminino , Marcadores Genéticos , Estudo de Associação Genômica Ampla , Humanos , Insulina/sangue , Neoplasias Renais/genética , Lipídeos/sangue , Masculino , Análise da Randomização Mendeliana , Obesidade/genética , Fatores de Risco
9.
Int J Genomics ; 2018: 7203469, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29850475

RESUMO

Monotropa hypopitys is a mycoheterotrophic, nonphotosynthetic plant acquiring nutrients from the roots of autotrophic trees through mycorrhizal symbiosis, and, similar to other extant plants, forming asymmetrical lateral organs during development. The members of the YABBY family of transcription factors are important players in the establishment of leaf and leaf-like organ polarity in plants. This is the first report on the identification of YABBY genes in a mycoheterotrophic plant devoid of aboveground vegetative organs. Seven M. hypopitys YABBY members were identified and classified into four clades. By structural analysis of putative encoded proteins, we confirmed the presence of YABBY-defining conserved domains and identified novel clade-specific motifs. Transcriptomic and qRT-PCR analyses of different tissues revealed MhyYABBY transcriptional patterns, which were similar to those of orthologous YABBY genes from other angiosperms. These data should contribute to the understanding of the role of the YABBY genes in the regulation of developmental and physiological processes in achlorophyllous leafless plants.

10.
Mitochondrial DNA B Resour ; 3(2): 1259-1260, 2018 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-33474484

RESUMO

Carnivorous plants have the ability to capture and digest small animals as a source of additional nutrients, which allows them to grow in nutrient-poor habitats. This study reports the complete mitochondrial genome sequence of a pitcher plant Nepenthes x ventrata. It was 520,764 bp in size with a GC content of 44.17% and contained 37 protein-coding genes, 2 pseudogenes, 18 tRNA genes and 3 rRNA genes. Four tRNA genes and the rps11 gene were probably transferred to mitochondrion form the chloroplast genome. Phylogenetic analysis confirmed that N. x ventrata belongs to the order Caryophyllales.

11.
Nat Commun ; 8: 15724, 2017 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-28598434

RESUMO

Previous genome-wide association studies (GWAS) have identified six risk loci for renal cell carcinoma (RCC). We conducted a meta-analysis of two new scans of 5,198 cases and 7,331 controls together with four existing scans, totalling 10,784 cases and 20,406 controls of European ancestry. Twenty-four loci were tested in an additional 3,182 cases and 6,301 controls. We confirm the six known RCC risk loci and identify seven new loci at 1p32.3 (rs4381241, P=3.1 × 10-10), 3p22.1 (rs67311347, P=2.5 × 10-8), 3q26.2 (rs10936602, P=8.8 × 10-9), 8p21.3 (rs2241261, P=5.8 × 10-9), 10q24.33-q25.1 (rs11813268, P=3.9 × 10-8), 11q22.3 (rs74911261, P=2.1 × 10-10) and 14q24.2 (rs4903064, P=2.2 × 10-24). Expression quantitative trait analyses suggest plausible candidate genes at these regions that may contribute to RCC susceptibility.


Assuntos
Carcinoma de Células Renais/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Neoplasias Renais/genética , Adolescente , Adulto , Idoso , Feminino , Loci Gênicos , Mutação em Linhagem Germinativa , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Polimorfismo de Nucleotídeo Único , População Branca/genética , Adulto Jovem
12.
Genom Data ; 11: 60-61, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27995074

RESUMO

Monotropa hypopitys (pinesap) is a non-photosynthetic obligately mycoheterotrophic plant of the family Ericaceae. It obtains the carbon and other nutrients from the roots of surrounding autotrophic trees through the associated mycorrhizal fungi. In order to understand the evolutionary changes in the plant genome associated with transition to a heterotrophic lifestyle, we performed de novo transcriptomic analysis of M. hypopitys using next-generation sequencing. We obtained the RNA-Seq data from flowers, flower bracts and roots with haustoria using Illumina HiSeq2500 platform. The raw data obtained in this study can be available in NCBI SRA database with accession number of SRP069226. A total of 10.3 GB raw sequence data were obtained, corresponding to 103,357,809 raw reads. A total of 103,025,683 reads were filtered after removing low-quality reads and trimming the adapter sequences. The Trinity program was used to de novo assemble 98,349 unigens with an N50 of 1342 bp. Using the TransDecoder program, we predicted 43,505 putative proteins. 38,416 unigenes were annotated in the Swiss-Prot protein sequence database using BLASTX. The obtained transcriptomic data will be useful for further studies of the evolution of plant genomes upon transition to a non-photosynthetic lifestyle and the loss of photosynthesis-related functions.

13.
Genome Announc ; 4(4)2016 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-27516508

RESUMO

We report here the draft genome sequences of two recently isolated magnetotactic species, Magnetospirillum moscoviense BB-1 and Magnetospirillum marisnigri SP-1. The genome of M. moscoviense BB-1 has 4,164,497 bp, 65.2% G+C content, and comprises 207 contigs. The genome of M. marisnigri SP-1 consists of 131 contigs and has a length of 4,619,819 bp and 64.7% G+C content.

14.
J Proteome Res ; 15(11): 4030-4038, 2016 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-27527821

RESUMO

A gene-centric approach was applied for a large-scale study of expression products of a single chromosome. Transcriptome profiling of liver tissue and HepG2 cell line was independently performed using two RNA-Seq platforms (SOLiD and Illumina) and also by Droplet Digital PCR (ddPCR) and quantitative RT-PCR. Proteome profiling was performed using shotgun LC-MS/MS as well as selected reaction monitoring with stable isotope-labeled standards (SRM/SIS) for liver tissue and HepG2 cells. On the basis of SRM/SIS measurements, protein copy numbers were estimated for the Chromosome 18 (Chr 18) encoded proteins in the selected types of biological material. These values were compared with expression levels of corresponding mRNA. As a result, we obtained information about 158 and 142 transcripts for HepG2 cell line and liver tissue, respectively. SRM/SIS measurements and shotgun LC-MS/MS allowed us to detect 91 Chr 18-encoded proteins in total, while an intersection between the HepG2 cell line and liver tissue proteomes was ∼66%. In total, there were 16 proteins specifically observed in HepG2 cell line, while 15 proteins were found solely in the liver tissue. Comparison between proteome and transcriptome revealed a poor correlation (R2 ≈ 0.1) between corresponding mRNA and protein expression levels. The SRM and shotgun data sets (obtained during 2015-2016) are available in PASSEL (PASS00697) and ProteomeExchange/PRIDE (PXD004407). All measurements were also uploaded into the in-house Chr 18 Knowledgebase at http://kb18.ru/protein/matrix/416126 .


Assuntos
Cromossomos Humanos Par 18 , Perfilação da Expressão Gênica , Proteoma/análise , Bases de Dados de Proteínas , Perfilação da Expressão Gênica/métodos , Células Hep G2 , Humanos , Fígado/química , Proteínas/análise , Proteoma/genética , Proteômica/métodos , RNA Mensageiro/análise
15.
Plant Mol Biol ; 91(4-5): 441-58, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27097902

RESUMO

Myco-heterotroph Monotropa hypopitys is a widely spread perennial herb used to study symbiotic interactions and physiological mechanisms underlying the development of non-photosynthetic plant. Here, we performed, for the first time, transcriptome-wide characterization of M. hypopitys miRNA profile using high throughput Illumina sequencing. As a result of small RNA library sequencing and bioinformatic analysis, we identified 55 members belonging to 40 families of known miRNAs and 17 putative novel miRNAs unique for M. hypopitys. Computational screening revealed 206 potential mRNA targets for known miRNAs and 31 potential mRNA targets for novel miRNAs. The predicted target genes were described in Gene Ontology terms and were found to be involved in a broad range of metabolic and regulatory pathways. The identification of novel M. hypopitys-specific miRNAs, some with few target genes and low abundances, suggests their recent evolutionary origin and participation in highly specialized regulatory mechanisms fundamental for non-photosynthetic biology of M. hypopitys. This global analysis of miRNAs and their potential targets in M. hypopitys provides a framework for further investigation of miRNA role in the evolution and establishment of non-photosynthetic myco-heterotrophs.


Assuntos
Ericaceae/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Sequenciamento de Nucleotídeos em Larga Escala/métodos , MicroRNAs/genética , Sequência de Bases , Sequência Conservada/genética , Ontologia Genética , MicroRNAs/metabolismo , Anotação de Sequência Molecular , Conformação de Ácido Nucleico , Filogenia , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo
16.
Mitochondrial DNA B Resour ; 1(1): 212-213, 2016 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-33473455

RESUMO

Plastid genomes of parasitic plants represent apt systems, in which the effects of relaxed selective pressure on photosynthetic function are studied. The complete chloroplast genome sequence of nonphotosynthetic mycoheterotrophic plant Monotropa hypopitys was determined. With only 19 protein-coding, four rRNA and 17 tRNA genes in 34 800 bp long genome, it is one of the most reduced plastid genomes characterized until now. Monotropa chloroplast genome lacks all genes encoding photosynthetic functions and RNA polymerase subunits but retains most of the ribosomal protein genes and housekeeping genes infA and matK. Monotropa represents the late stages of chloroplast genome decay following the transition to heterotrophy.

17.
BMC Plant Biol ; 16(Suppl 3): 238, 2016 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-28105941

RESUMO

BACKGROUND: Chloroplasts of most plants are responsible for photosynthesis and contain a conserved set of about 110 genes that encode components of housekeeping gene expression machinery and photosynthesis-related functions. Heterotrophic plants obtaining nutrients from other organisms and their plastid genomes represent model systems in which to study the effects of relaxed selective pressure on photosynthetic function. The most evident is a reduction in the size and gene content of the plastome, which correlates with the loss of genes encoding photosynthetic machinery which become unnecessary. Transition to a non-photosynthetic lifestyle is expected also to relax the selective pressure on photosynthetic machinery in the nuclear genome, however, the corresponding changes are less known. RESULTS: Here we report the complete sequence of the plastid genome of Monotropa hypopitys, an achlorophyllous obligately mycoheterotrophic plant belonging to the family Ericaceae. The plastome of M. hypopitys is greatly reduced in size (35,336 bp) and lacks the typical quadripartite structure with two single-copy regions and an inverted repeat. Only 45 genes remained presumably intact- those encoding ribosomal proteins, ribosomal and transfer RNA and housekeeping genes infA, matK, accD and clpP. The clpP and accD genes probably remain functional, although their sequences are highly diverged. The sets of genes for ribosomal protein and transfer RNA are incomplete relative to chloroplasts of a photosynthetic plant. Comparison of the plastid genomes of two subspecies-level isolates of M. hypopitys revealed major structural rearrangements associated with repeat-driven recombination and the presence of isolate-specific tRNA genes. Analysis of the M. hypopitys transcriptome by RNA-Seq showed the absence of expression of nuclear-encoded components of photosystem I and II reaction center proteins, components of cytochrome b6f complex, ATP synthase, ribulose bisphosphate carboxylase components, as well as chlorophyll from protoporphyrin IX biosynthesis pathway. CONCLUSIONS: With the complete loss of genes related to photosynthesis, NADH dehydrogenase, plastid-encoded RNA polymerase and ATP synthase, the M. hypopitys plastid genome is among the most functionally reduced ones characteristic of obligate non-photosynthetic parasitic species. Analysis of the M. hypopitys transcriptome revealed coordinated evolution of the nuclear and plastome genomes and the loss of photosynthesis-related functions in both genomes.


Assuntos
Ericaceae/genética , Genoma de Planta/genética , Genomas de Plastídeos/genética , Fotossíntese/genética , Proteínas de Plantas/genética , Sequência de Aminoácidos , Evolução Biológica , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Alinhamento de Sequência
19.
Indian J Microbiol ; 55(4): 440-6, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26543270

RESUMO

Pravastatin is one of the most popular cholesterol-lowering drugs. Its industrial production represents a two-stage process including the microbial production of compactin and its further biocatalytic conversion to pravastatin. To increase a conversion rate, a higher compactin content in fermentation medium should be used; however, high compactin concentrations inhibit microbial growth. Therefore, the improvement of the compactin resistance of a producer still remains a relevant problem. A multi-step random UV mutagenesis of a Streptomyces xanthochromogenes strain RIA 1098 and the further selection of high-yield compactin-resistant mutants have resulted in a highly productive compactin-resistant strain S 33-1. After the fermentation medium improvement, the maximum bioconversion rate of this strain has reached 91 % at the daily compactin dose equal to 1 g/L and still remained high (83 %) even at the doubled dose (2 g/L). A 1-year study of the mutant strain stability has proved a stable inheritance of its characteristics that provides this strain to be very promising for the pravastatin-producing industry.

20.
Vaccine ; 33(29): 3392-7, 2015 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-25937448

RESUMO

The extracellular domain of the transmembrane protein M2 (M2e) of influenza A virus is a promising target for the development of "universal" vaccines against influenza. M2e is a poor immunogen by itself; however, when M2e is linked to an appropriate carrier, such as hepatitis B virus core (HBc) particles, it becomes highly immunogenic. Insertions of target peptides into the surface-exposed major immunodominant loop region (MIR) of the HBc antigen are especially immunogenic, but such insertions often affect the protein folding and formation of recombinant virus-like particles. To facilitate an appropriate conformation of the M2e insert, we introduced flexible linkers at the junction points between the insert and flanking HBc sequences. This approach allowed the construction of recombinant HBc particles carrying 1, 2 and 4 copies of M2e in the MIR region. These particles were produced in Escherichia coli and purified to homogeneity. The immune response and protective activity of hybrid HBc particles in mice correlated with the number of inserted M2e peptides: the highest immunogenicity and complete protection of mice against the lethal challenge by influenza virus was observed with particles carrying four copies of M2e. The possibility of the simultaneous presentation of M2e peptides from several important influenza strains on a single HBc particle could also facilitate the development of a broad-specificity vaccine efficient not only against influenza A strains of human origin but also for newly emerging strains of animal origin, such as the avian influenza.


Assuntos
Epitopos/imunologia , Vacinas contra Influenza/imunologia , Vacinas de Partículas Semelhantes a Vírus/imunologia , Proteínas da Matriz Viral/imunologia , Animais , Modelos Animais de Doenças , Epitopos/genética , Escherichia coli/genética , Feminino , Expressão Gênica , Antígenos do Núcleo do Vírus da Hepatite B/genética , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/genética , Camundongos Endogâmicos BALB C , Mutagênese Insercional , Infecções por Orthomyxoviridae/prevenção & controle , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Análise de Sobrevida , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Vacinas de Partículas Semelhantes a Vírus/administração & dosagem , Vacinas de Partículas Semelhantes a Vírus/genética , Proteínas da Matriz Viral/genética
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