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1.
Sci Rep ; 12(1): 17498, 2022 10 19.
Article in English | MEDLINE | ID: mdl-36261669

ABSTRACT

Urban waterbodies are one of the most pertinent issues involved in multiple aspects of Sustainable Development Goals (SDGs). However, waterbodies in large Chinese cities are highly vulnerable to urban-land expansion, which is mostly due to economic development, population growth, and rural-urban migration. In this work, we selected 159 Chinese cities of over one million in population to investigate the encroachment on waterbodies due to rapid urbanization from 1990 to 2018. Overall, 20.6% of natural waterbody area was lost during this period to urban expansion, and this fraction varied from city to city which was related to waterbody abundance. With the acceleration of urbanization, waterbody occupation is becoming more serious (P < 0.01). However, in all cities, this encroachment has eased since 2010, which justifies the effective implementation of national-scale policies to conserve urban waterbodies. Meanwhile, gains have occurred during urbanization, in addition to the loss of waterbodies. Especially, cities lacking waterbody placed a greater emphasis on ecological factors, whose urban waterbody areas showed an increasing trend. In the future, ecological resources, including waterbody, should be considered in urban planning to provide reasonable protection to waterbodies in the quest for urban sustainability.


Subject(s)
Sustainable Growth , Urbanization , Humans , Cities , Population Dynamics , China , Urban Population
2.
Ann Rheum Dis ; 81(3): 406-415, 2022 03.
Article in English | MEDLINE | ID: mdl-34789453

ABSTRACT

OBJECTIVES: Drug reaction with eosinophilia and systemic symptoms (DRESS) is a severe, delayed hypersensitivity reaction (DHR). We observed DRESS to inhibitors of interleukin 1 (IL-1) or IL-6 in a small group of patients with Still's disease with atypical lung disease. We sought to characterise features of patients with Still's disease with DRESS compared with drug-tolerant Still's controls. We analysed human leucocyte antigen (HLA) alleles for association to inhibitor-related DHR, including in a small Kawasaki disease (KD) cohort. METHODS: In a case/control study, we collected a multicentre series of patients with Still's disease with features of inhibitor-related DRESS (n=66) and drug-tolerant Still's controls (n=65). We retrospectively analysed clinical data from all Still's subjects and typed 94/131 for HLA. European Still's-DRESS cases were ancestry matched to International Childhood Arthritis Genetics Consortium paediatric Still's cases (n=550) and compared for HLA allele frequencies. HLA association also was analysed using Still's-DRESS cases (n=64) compared with drug-tolerant Still's controls (n=30). KD subjects (n=19) were similarly studied. RESULTS: Still's-DRESS features included eosinophilia (89%), AST-ALT elevation (75%) and non-evanescent rash (95%; 88% involving face). Macrophage activation syndrome during treatment was frequent in Still's-DRESS (64%) versus drug-tolerant Still's (3%; p=1.2×10-14). We found striking enrichment for HLA-DRB1*15 haplotypes in Still's-DRESS cases versus INCHARGE Still's controls (p=7.5×10-13) and versus self-identified, ancestry-matched Still's controls (p=6.3×10-10). In the KD cohort, DRB1*15:01 was present only in those with suspected anakinra reactions. CONCLUSIONS: DRESS-type reactions occur among patients treated with IL-1/IL-6 inhibitors and strongly associate with common HLA-DRB1*15 haplotypes. Consideration of preprescription HLA typing and vigilance for serious reactions to these drugs are warranted.


Subject(s)
Antirheumatic Agents/adverse effects , HLA-DRB1 Chains/genetics , Hypersensitivity, Delayed/genetics , Still's Disease, Adult-Onset/drug therapy , Still's Disease, Adult-Onset/genetics , Adult , Alleles , Case-Control Studies , Drug Hypersensitivity Syndrome/genetics , Drug Hypersensitivity Syndrome/immunology , Drug Tolerance/genetics , Female , HLA-DRB1 Chains/immunology , Haplotypes , Humans , Hypersensitivity, Delayed/immunology , Interleukin-1/antagonists & inhibitors , Interleukin-6/antagonists & inhibitors , Male , Mucocutaneous Lymph Node Syndrome/drug therapy , Mucocutaneous Lymph Node Syndrome/genetics , Retrospective Studies , Still's Disease, Adult-Onset/immunology
3.
PLoS Genet ; 17(7): e1009675, 2021 07.
Article in English | MEDLINE | ID: mdl-34324497

ABSTRACT

Emerging evidence indicates that tRNA-derived small RNAs (tsRNAs) are involved in fine-tuning gene expression and become dysregulated in various cancers. We recently showed that the 22nt LeuCAG3´tsRNA from the 3´ end of tRNALeu is required for efficient translation of a ribosomal protein mRNA and ribosome biogenesis. Inactivation of this 3´tsRNA induced apoptosis in rapidly dividing cells and suppressed the growth of a patient-derived orthotopic hepatocellular carcinoma in mice. The mechanism involved in the generation of the 3´tsRNAs remains elusive and it is unclear if the 3´-ends of 3´tsRNAs are aminoacylated. Here we report an enzymatic method utilizing exonuclease T to determine the 3´charging status of tRNAs and tsRNAs. Our results showed that the LeuCAG3´tsRNA, and two other 3´tsRNAs are fully aminoacylated. When the leucyl-tRNA synthetase (LARS1) was inhibited, there was no change in the total tRNALeu concentration but a reduction in both the charged tRNALeu and LeuCAG3´tsRNA, suggesting the 3´tsRNAs are fully charged and originated solely from the charged mature tRNA. Altering LARS1 expression or the expression of various tRNALeu mutants were also shown to affect the generation of the LeuCAG3´tsRNA further suggesting they are created in a highly regulated process. The fact that the 3´tsRNAs are aminoacylated and their production is regulated provides additional insights into their importance in post-transcriptional gene regulation that includes coordinating the production of the protein synthetic machinery.


Subject(s)
RNA, Transfer/biosynthesis , RNA, Transfer/genetics , Transfer RNA Aminoacylation/genetics , Amino Acids/genetics , Gene Expression/genetics , Gene Expression Regulation/genetics , HeLa Cells , Humans , Leucine/genetics , Leucine/metabolism , RNA Processing, Post-Transcriptional , RNA, Small Untranslated/genetics , RNA, Small Untranslated/metabolism , RNA, Transfer/metabolism , Ribosomal Proteins , Transfer RNA Aminoacylation/physiology
4.
Nat Commun ; 12(1): 3397, 2021 06 07.
Article in English | MEDLINE | ID: mdl-34099665

ABSTRACT

It is known that an RNA's structure determines its biological function, yet current RNA structure probing methods only capture partial structure information. The ability to measure intact (i.e., full length) RNA structures will facilitate investigations of the functions and regulation mechanisms of small RNAs and identify short fragments of functional sites. Here, we present icSHAPE-MaP, an approach combining in vivo selective 2'-hydroxyl acylation and mutational profiling to probe intact RNA structures. We further showcase the RNA structural landscape of substrates bound by human Dicer based on the combination of RNA immunoprecipitation pull-down and icSHAPE-MaP small RNA structural profiling. We discover distinct structural categories of Dicer substrates in correlation to both their binding affinity and cleavage efficiency. And by tertiary structural modeling constrained by icSHAPE-MaP RNA structural data, we find the spatial distance measuring as an influential parameter for Dicer cleavage-site selection.


Subject(s)
DEAD-box RNA Helicases/metabolism , Nucleic Acid Conformation , RNA/chemistry , Ribonuclease III/metabolism , Computational Biology , DEAD-box RNA Helicases/genetics , Gene Knockdown Techniques , HEK293 Cells , Humans , Mutagenesis, Site-Directed , Protein Binding/genetics , RNA/genetics , RNA/metabolism , RNA Probes , RNA-Seq , Ribonuclease III/genetics , Substrate Specificity/genetics
5.
Hum Gene Ther ; 31(9-10): 553-564, 2020 05.
Article in English | MEDLINE | ID: mdl-32024384

ABSTRACT

Despite early successes using recombinant adeno-associated virus (rAAV) vectors in clinical gene therapy trials, limitations remain making additional advancements a necessity. Some of the challenges include variable levels of pre-existing neutralizing antibodies and poor transduction in specific target tissues and/or diseases. In addition, readministration of an rAAV vector is in general not possible due to the immune response against the capsid. Recombinant adeno-associated virus (AAV) vectors with novel capsids can be isolated in nature or developed through different directed evolution strategies. However, in most cases, the process of AAV selection is not well understood and new strategies are required to define the best parameters to develop more efficient and functional rAAV capsids. Therefore, the use of barcoding for AAV capsid libraries, which can be screened by high-throughput sequencing, provides a powerful tool to track AAV capsid evolution and potentially improve AAV capsid library screens. In this study, we examined how different parameters affect the screen of two different AAV libraries in two human cell types. We uncovered new and unexpected insights in how to maximize the likelihood of obtaining AAV variants with the desired properties. The major findings of the study are the following. (1) Inclusion of helper-virus for AAV replication can selectively propagate variants that can replicate to higher titers, but are not necessarily better at transduction. (2) Competition between AAVs with specific capsids can take place in cells that have been infected with different AAVs. (3) The use of low multiplicity of infections for infection results in more variation between screens and is not optimal at selecting the most desired capsids. (4) Using multiple rounds of selection can be counterproductive. We conclude that each of these parameters should be taken into consideration when screening AAV libraries for enhanced properties of interest.


Subject(s)
Capsid/metabolism , Dependovirus/genetics , Genetic Vectors/genetics , Biodiversity , Cell Line , Directed Molecular Evolution , Gene Library , Gene Transfer Techniques , Genome, Viral , HaCaT Cells , Helper Viruses , High-Throughput Nucleotide Sequencing , Humans , Reproducibility of Results , Transduction, Genetic , Virus Replication
6.
Cell Rep ; 29(12): 3816-3824.e4, 2019 12 17.
Article in English | MEDLINE | ID: mdl-31851915

ABSTRACT

tRNA-derived small RNAs (tsRNAs) have been implicated in many cellular processes, yet the detailed mechanisms are not well defined. We previously found that the 3' end of Leu-CAG tRNA-derived small RNA (LeuCAG3'tsRNA) regulates ribosome biogenesis in humans by maintaining ribosomal protein S28 (RPS28) levels. The tsRNA binds to coding (CDS) and non-coding 3' UTR sequence in the RPS28 mRNA, altering its secondary structure and enhancing its translation. Here we report that the functional 3' UTR target site is present in primates while the CDS target site is present in many vertebrates. We establish that this tsRNA also regulates mouse Rps28 translation by interacting with the CDS target site. We further establish that the change in mRNA translation occurred at a post-initiation step in both species. Overall, our results suggest that LeuCAG3'tsRNA might maintain ribosome biogenesis through a conserved gene regulatory mechanism in vertebrates.


Subject(s)
Leucine/genetics , Protein Biosynthesis , Protein Processing, Post-Translational , RNA, Messenger/genetics , RNA, Small Untranslated/genetics , RNA, Transfer/genetics , Ribosomal Proteins/metabolism , Animals , Humans , Leucine/metabolism , Mice , Phylogeny , RNA, Messenger/metabolism , RNA, Small Untranslated/metabolism , RNA, Transfer/metabolism , Ribosomal Proteins/genetics
7.
JCI Insight ; 4(22)2019 11 14.
Article in English | MEDLINE | ID: mdl-31723052

ABSTRACT

While gene transfer using recombinant adeno-associated viral (rAAV) vectors has shown success in some clinical trials, there remain many tissues that are not well transduced. Because of the recent success in reprogramming islet-derived cells into functional ß cells in animal models, we constructed 2 highly complex barcoded replication competent capsid shuffled libraries and selected for high-transducing variants on primary human islets. We describe the generation of a chimeric AAV capsid (AAV-KP1) that facilitates transduction of primary human islet cells and human embryonic stem cell-derived ß cells with up to 10-fold higher efficiency compared with previously studied best-in-class AAV vectors. Remarkably, this chimeric capsid also enabled transduction of both mouse and human hepatocytes at very high levels in a humanized chimeric mouse model, thus providing a versatile vector that has the potential to be used in both preclinical testing and human clinical trials for liver-based diseases and diabetes.


Subject(s)
Capsid/chemistry , Dependovirus/genetics , Genetic Therapy/methods , Genetic Vectors/genetics , Animals , Cells, Cultured , Diabetes Mellitus , Embryonic Stem Cells/cytology , Embryonic Stem Cells/metabolism , Gene Library , Gene Transfer Techniques , HEK293 Cells , Hepatocytes/cytology , Hepatocytes/metabolism , Humans , Islets of Langerhans/cytology , Islets of Langerhans/metabolism , Mice
8.
Ann Rheum Dis ; 78(12): 1722-1731, 2019 12.
Article in English | MEDLINE | ID: mdl-31562126

ABSTRACT

OBJECTIVE: To investigate the characteristics and risk factors of a novel parenchymal lung disease (LD), increasingly detected in systemic juvenile idiopathic arthritis (sJIA). METHODS: In a multicentre retrospective study, 61 cases were investigated using physician-reported clinical information and centralised analyses of radiological, pathological and genetic data. RESULTS: LD was associated with distinctive features, including acute erythematous clubbing and a high frequency of anaphylactic reactions to the interleukin (IL)-6 inhibitor, tocilizumab. Serum ferritin elevation and/or significant lymphopaenia preceded LD detection. The most prevalent chest CT pattern was septal thickening, involving the periphery of multiple lobes ± ground-glass opacities. The predominant pathology (23 of 36) was pulmonary alveolar proteinosis and/or endogenous lipoid pneumonia (PAP/ELP), with atypical features including regional involvement and concomitant vascular changes. Apparent severe delayed drug hypersensitivity occurred in some cases. The 5-year survival was 42%. Whole exome sequencing (20 of 61) did not identify a novel monogenic defect or likely causal PAP-related or macrophage activation syndrome (MAS)-related mutations. Trisomy 21 and young sJIA onset increased LD risk. Exposure to IL-1 and IL-6 inhibitors (46 of 61) was associated with multiple LD features. By several indicators, severity of sJIA was comparable in drug-exposed subjects and published sJIA cohorts. MAS at sJIA onset was increased in the drug-exposed, but was not associated with LD features. CONCLUSIONS: A rare, life-threatening lung disease in sJIA is defined by a constellation of unusual clinical characteristics. The pathology, a PAP/ELP variant, suggests macrophage dysfunction. Inhibitor exposure may promote LD, independent of sJIA severity, in a small subset of treated patients. Treatment/prevention strategies are needed.


Subject(s)
Arthritis, Juvenile/complications , Lung Diseases/epidemiology , Lung/diagnostic imaging , Biopsy , Child , Child, Preschool , Female , Follow-Up Studies , Humans , Incidence , Infant , Lung Diseases/diagnosis , Lung Diseases/etiology , Male , Prognosis , Retrospective Studies , Survival Rate/trends , Tomography, X-Ray Computed , United States/epidemiology
9.
Nat Commun ; 9(1): 5321, 2018 12 14.
Article in English | MEDLINE | ID: mdl-30552326

ABSTRACT

miR-122 is a highly expressed liver microRNA that is activated perinatally and aids in regulating cholesterol metabolism and promoting terminal differentiation of hepatocytes. Disrupting expression of miR-122 can re-activate embryo-expressed adult-silenced genes, ultimately leading to the development of hepatocellular carcinoma (HCC). Here we interrogate the liver transcriptome at various time points after genomic excision of miR-122 to determine the cellular consequences leading to oncogenesis. Loss of miR-122 leads to specific and progressive increases in expression of imprinted clusters of microRNAs and mRNA transcripts at the Igf2 and Dlk1-Dio3 loci that could be curbed by re-introduction of exogenous miR-122. mRNA targets of other abundant hepatic microRNAs are functionally repressed leading to widespread hepatic transcriptional de-regulation. Together, this reveals a transcriptomic framework for the hepatic response to loss of miR-122 and the outcome on other microRNAs and their cognate gene targets.


Subject(s)
Carcinoma, Hepatocellular/metabolism , Gene Expression Regulation, Neoplastic/genetics , Liver Neoplasms/metabolism , Liver/metabolism , MicroRNAs/genetics , MicroRNAs/metabolism , Animals , Calcium-Binding Proteins , Carcinogenesis/genetics , Carcinogenesis/metabolism , Carcinoma, Hepatocellular/genetics , Gene Expression Profiling , HEK293 Cells , Hepatocytes/metabolism , Humans , Insulin-Like Growth Factor II , Intercellular Signaling Peptides and Proteins/metabolism , Iodide Peroxidase/metabolism , Liver Neoplasms/genetics , Membrane Proteins/metabolism , Mice , Mice, Knockout , RNA, Messenger/metabolism , Transcriptome
10.
Mol Ther Methods Clin Dev ; 10: 144-155, 2018 Sep 21.
Article in English | MEDLINE | ID: mdl-30101152

ABSTRACT

Skeletal muscle is ideal for passive vaccine administration as it is easily accessible by intramuscular injection. Recombinant adeno-associated virus (rAAV) vectors are in consideration for passive vaccination clinical trials for HIV and influenza. However, greater human skeletal muscle transduction is needed for therapeutic efficacy than is possible with existing serotypes. To bioengineer capsids with therapeutic levels of transduction, we utilized a directed evolution approach to screen libraries of shuffled AAV capsids in pools of surgically resected human skeletal muscle cells from five patients. Six rounds of evolution were performed in various muscle cell types, and evolved variants were validated against existing muscle-tropic serotypes rAAV1, 6, and 8. We found that evolved variants NP22 and NP66 had significantly increased primary human and rhesus skeletal muscle fiber transduction from surgical explants ex vivo and in various primary and immortalized myogenic lines in vitro. Importantly, we demonstrated reduced seroreactivity compared to existing serotypes against normal human serum from 50 adult donors. These capsids represent powerful tools for human skeletal muscle expression and secretion of antibodies from passive vaccines.

11.
Mol Ther ; 26(1): 289-303, 2018 01 03.
Article in English | MEDLINE | ID: mdl-29055620

ABSTRACT

Existing recombinant adeno-associated virus (rAAV) serotypes for delivering in vivo gene therapy treatments for human liver diseases have not yielded combined high-level human hepatocyte transduction and favorable humoral neutralization properties in diverse patient groups. Yet, these combined properties are important for therapeutic efficacy. To bioengineer capsids that exhibit both unique seroreactivity profiles and functionally transduce human hepatocytes at therapeutically relevant levels, we performed multiplexed sequential directed evolution screens using diverse capsid libraries in both primary human hepatocytes in vivo and with pooled human sera from thousands of patients. AAV libraries were subjected to five rounds of in vivo selection in xenografted mice with human livers to isolate an enriched human-hepatotropic library that was then used as input for a sequential on-bead screen against pooled human immunoglobulins. Evolved variants were vectorized and validated against existing hepatotropic serotypes. Two of the evolved AAV serotypes, NP40 and NP59, exhibited dramatically improved functional human hepatocyte transduction in vivo in xenografted mice with human livers, along with favorable human seroreactivity profiles, compared with existing serotypes. These novel capsids represent enhanced vector delivery systems for future human liver gene therapy applications.


Subject(s)
Capsid Proteins/genetics , Dependovirus/genetics , Genetic Engineering , Genetic Vectors/genetics , Liver/metabolism , Transduction, Genetic , Animals , Capsid Proteins/chemistry , Female , Gene Transfer Techniques , Hepatocytes/metabolism , Heterografts , Humans , Male , Mice , Models, Molecular , Protein Conformation
12.
Nature ; 552(7683): 57-62, 2017 12 07.
Article in English | MEDLINE | ID: mdl-29186115

ABSTRACT

Transfer-RNA-derived small RNAs (tsRNAs; also called tRNA-derived fragments) are an abundant class of small non-coding RNAs whose biological roles are not well understood. Here we show that inhibition of a specific tsRNA, LeuCAG3'tsRNA, induces apoptosis in rapidly dividing cells in vitro and in a patient-derived orthotopic hepatocellular carcinoma model in mice. This tsRNA binds at least two ribosomal protein mRNAs (RPS28 and RPS15) to enhance their translation. A decrease in translation of RPS28 mRNA blocks pre-18S ribosomal RNA processing, resulting in a reduction in the number of 40S ribosomal subunits. These data establish a post-transcriptional mechanism that can fine-tune gene expression during different physiological states and provide a potential new target for treating cancer.


Subject(s)
RNA, Small Untranslated/genetics , RNA, Transfer, Leu/genetics , Ribosomal Proteins/biosynthesis , Ribosomes/genetics , Ribosomes/metabolism , Animals , Apoptosis/drug effects , Apoptosis/genetics , Base Pairing , Base Sequence , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/pathology , Carcinoma, Hepatocellular/therapy , Cell Proliferation/drug effects , Cell Proliferation/genetics , Cell Survival/drug effects , Cell Survival/genetics , Female , HCT116 Cells , HEK293 Cells , HeLa Cells , Humans , Liver Neoplasms/genetics , Liver Neoplasms/pathology , Liver Neoplasms/therapy , Male , Mice , Oligonucleotides, Antisense/genetics , Oligonucleotides, Antisense/pharmacology , Oligonucleotides, Antisense/therapeutic use , Protein Biosynthesis/drug effects , Protein Biosynthesis/genetics , RNA, Messenger/chemistry , RNA, Messenger/genetics , RNA, Messenger/metabolism , RNA, Ribosomal, 18S/genetics , RNA, Ribosomal, 18S/metabolism , RNA, Small Untranslated/antagonists & inhibitors , RNA, Transfer, Leu/antagonists & inhibitors , Ribosomal Proteins/genetics , Ribosome Subunits, Small, Eukaryotic/metabolism , Ribosomes/drug effects , Substrate Specificity/genetics , Xenograft Model Antitumor Assays
13.
BMC Res Notes ; 8: 72, 2015 Mar 08.
Article in English | MEDLINE | ID: mdl-25889517

ABSTRACT

BACKGROUND: Whole-exome sequencing (WES) is a popular next-generation sequencing technology used by numerous laboratories with various levels of statistical and analytical expertise. Centralized databases, such as the Sequence Read Archive and the European Nucleotide Archive, allow data to be reanalyzed by independent labs to confirm results and derive additional insights. Access to new and shared data highlights the necessity for software that both lowers the statistical and analytical expertise required to generate results and promotes reproducible methodology among laboratories. FINDINGS: We have developed fastq2vcf, a pipeline that automates the genomic variant calling process using multiple callers. Fastq2vcf offers improved flexibility, efficiency, and reproducibility by seamlessly integrating several leading sequencing analysis tools. It outputs not only the annotated variant call set for each caller, but also the consensus variant call set shared by different callers. Furthermore, it can be customized and extended easily. CONCLUSIONS: Our software tool automatically generates executable command lines for a variety of tools required for analyzing WES data. It is also highly configurable and provides users with complete control of the processing procedure, making it easy to submit and track jobs in both single workstation and parallelized computing environments. By using this pipeline, WES analysis can be easily reproduced.


Subject(s)
Exome , High-Throughput Nucleotide Sequencing/methods , Software , Benchmarking , Humans , Quality Control , Reproducibility of Results
14.
Cancer Res ; 74(12): 3228-37, 2014 Jun 15.
Article in English | MEDLINE | ID: mdl-24713434

ABSTRACT

Prostate cancer remains the second leading cause of cancer death in American men and there is an unmet need for biomarkers to identify patients with aggressive disease. In an effort to identify biomarkers of recurrence, we performed global RNA sequencing on 106 formalin-fixed, paraffin-embedded prostatectomy samples from 100 patients at three independent sites, defining a 24-gene signature panel. The 24 genes in this panel function in cell-cycle progression, angiogenesis, hypoxia, apoptosis, PI3K signaling, steroid metabolism, translation, chromatin modification, and transcription. Sixteen genes have been associated with cancer, with five specifically associated with prostate cancer (BTG2, IGFBP3, SIRT1, MXI1, and FDPS). Validation was performed on an independent publicly available dataset of 140 patients, where the new signature panel outperformed markers published previously in terms of predicting biochemical recurrence. Our work also identified differences in gene expression between Gleason pattern 4 + 3 and 3 + 4 tumors, including several genes involved in the epithelial-to-mesenchymal transition and developmental pathways. Overall, this study defines a novel biomarker panel that has the potential to improve the clinical management of prostate cancer.


Subject(s)
Biomarkers, Tumor/metabolism , Neoplasm Recurrence, Local/metabolism , Prostatic Neoplasms/metabolism , Transcriptome , Adult , Biomarkers, Tumor/genetics , Fixatives/chemistry , Formaldehyde/chemistry , Gene Expression Profiling , Humans , Kaplan-Meier Estimate , Male , Neoplasm Grading , Neoplasm Recurrence, Local/mortality , Neoplasm Recurrence, Local/pathology , Proportional Hazards Models , Prostatic Neoplasms/mortality , Prostatic Neoplasms/pathology , Sequence Analysis, RNA
15.
Infect Genet Evol ; 22: 192-200, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24161299

ABSTRACT

While the nonstructural gene (NS) of the influenza A virus plays a crucial role in viral virulence and replication, the complete understanding of its molecular phylogeny and evolutionary dynamics remains lacking. In this study, the phylogenetic analysis of 7581 NS sequences revealed ten distinct lineages within alleles A and B: three host-specific (human, classical swine and equine), two reassortment-originated (A(H1N1)pdm09 and triple reassortment swine), one transmission-originated (Eurasian swine), and two geographically isolated avian (Eurasian/Oceanian and North American) for allele A and two geographically isolated avian (Eurasian/Oceanian and North American) for allele B. The average nucleotide substitution rates of the lineages range from 1.24×10(-3) (equine) to 4.34×10(-3) (A(H1N1)pdm09) substitutions per site per year. The selection pressure analysis demonstrated that the dN/dS ratio of the NS gene in A(H1N1)pdm09 lineage was higher than its closely related triple reassortant swine, which could be attributed to the adaptation to the new host and/or intensive surveillance after the inter-species transmission from swine to human. The positive selection sites were found in all lineages except the equine lineage and mostly in the NS1 region. The positive selection sites 22, 26, 226, 227 and 230 of the human lineage are significant because these residues participate in either forming the dimerization of the two RNA binding domain (RBD) monomers or blocking the replication of host genes. Residues at position 171 provide hydrophobic interactions with hydrophobic residues at p85ß and thus induce viral cell growth. The lineages and evolutionary dynamics of influenza A NS gene obtained in this study, along with the studies of other gene segments, are expected to improve the early detection of new viruses and thus have the potential to enhance influenza surveillance.


Subject(s)
Evolution, Molecular , Influenza A virus/classification , Influenza A virus/genetics , Orthomyxoviridae Infections/virology , Viral Nonstructural Proteins/genetics , Animals , Birds , Horses , Humans , Influenza, Human/virology , Phylogeny , Swine , Viral Nonstructural Proteins/chemistry
16.
PLoS One ; 7(7): e38665, 2012.
Article in English | MEDLINE | ID: mdl-22808012

ABSTRACT

BACKGROUND: Influenza neuraminidase (NA) is an important surface glycoprotein and plays a vital role in viral replication and drug development. The NA is found in influenza A and B viruses, with nine subtypes classified in influenza A. The complete knowledge of influenza NA evolutionary history and phylodynamics, although critical for the prevention and control of influenza epidemics and pandemics, remains lacking. METHODOLOGY/PRINCIPAL FINDINGS: Evolutionary and phylogenetic analyses of influenza NA sequences using Maximum Likelihood and Bayesian MCMC methods demonstrated that the divergence of influenza viruses into types A and B occurred earlier than the divergence of influenza A NA subtypes. Twenty-three lineages were identified within influenza A, two lineages were classified within influenza B, and most lineages were specific to host, subtype or geographical location. Interestingly, evolutionary rates vary not only among lineages but also among branches within lineages. The estimated tMRCAs of influenza lineages suggest that the viruses of different lineages emerge several months or even years before their initial detection. The d(N)/d(S) ratios ranged from 0.062 to 0.313 for influenza A lineages, and 0.257 to 0.259 for influenza B lineages. Structural analyses revealed that all positively selected sites are at the surface of the NA protein, with a number of sites found to be important for host antibody and drug binding. CONCLUSIONS/SIGNIFICANCE: The divergence into influenza type A and B from a putative ancestral NA was followed by the divergence of type A into nine NA subtypes, of which 23 lineages subsequently diverged. This study provides a better understanding of influenza NA lineages and their evolutionary dynamics, which may facilitate early detection of newly emerging influenza viruses and thus improve influenza surveillance.


Subject(s)
Influenza A virus/genetics , Influenza B virus/genetics , Neuraminidase/genetics , Phylogeny , Viral Proteins/genetics , Animals , Bayes Theorem , Biological Evolution , Birds/virology , Humans , Influenza A virus/classification , Influenza A virus/enzymology , Influenza B virus/classification , Influenza B virus/enzymology , Influenza in Birds/virology , Influenza, Human/virology , Models, Molecular , Neuraminidase/classification , Orthomyxoviridae Infections/virology , Sequence Analysis, DNA , Viral Proteins/classification
17.
Infect Genet Evol ; 11(8): 2125-32, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21763464

ABSTRACT

Influenza A viral nucleoprotein (NP) plays a critical role in virus replication and host adaptation, however, the underlying molecular evolutionary dynamics of NP lineages are less well-understood. In this study, large-scale analyses of 5094 NP nucleotide sequences revealed eight distinct evolutionary lineages, including three host-specific lineages (human, classical swine and equine), two cross-host lineages (Eurasian avian-like swine and swine-origin human pandemic H1N1 2009) and three geographically isolated avian lineages (Eurasian, North American and Oceanian). The average nucleotide substitution rate of the NP lineages was estimated to be 2.4 × 10(-3) substitutions per site per year, with the highest value observed in pandemic H1N1 2009 (3.4 × 10(-3)) and the lowest in equine (0.9 × 10(-3)). The estimated time of most recent common ancestor (TMRCA) for each lineage demonstrated that the earliest human lineage was derived around 1906, and the latest pandemic H1N1 2009 lineage dated back to December 17, 2008. A marked time gap was found between the times when the viruses emerged and were first sampled, suggesting the crucial role for long-term surveillance of newly emerging viruses. The selection analyses showed that human lineage had six positive selection sites, whereas pandemic H1N1 2009, classical swine, Eurasian avian and Eurasian swine had only one or two sites. Protein structure analyses revealed several positive selection sites located in epitope regions or host adaptation regions, indicating strong adaptation to host immune system pressures in influenza viruses. Along with previous studies, this study provides new insights into the evolutionary dynamics of influenza A NP lineages. Further lineage analyses of other gene segments will allow better understanding of influenza A virus evolution and assist in the improvement of global influenza surveillance.


Subject(s)
Evolution, Molecular , Influenza A Virus, H1N1 Subtype/genetics , Nucleoproteins/classification , Nucleoproteins/genetics , Viral Proteins/classification , Viral Proteins/genetics , Animals , Base Sequence , Humans , Influenza A Virus, H1N1 Subtype/classification , Influenza, Human/genetics , Influenza, Human/virology , Molecular Sequence Data , Nucleoproteins/chemistry , Orthomyxoviridae Infections/genetics , Orthomyxoviridae Infections/virology , Pandemics , Phylogeny , Protein Conformation , Sequence Alignment , Sequence Analysis, RNA , Swine , Viral Proteins/chemistry
20.
Infect Genet Evol ; 11(5): 803-11, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21382522

ABSTRACT

The pandemic (H1N1) 2009 virus is unique in many aspects, especially in its genetics and evolution. In this paper, we examine the molecular mechanisms underlying the evolution of this novel virus through a comprehensive bioinformatics analysis, and present results in the context of a review of the literature. The pandemic virus was found to arise from a reassortment of two swine viruses, each of which ultimately arose from interspecies transmission. It experienced fast evolutionary rates and strong selection pressures, diverging into two different clusters at the early pandemic stage. Cluster I became extinct at the end of 2009 whereas Cluster II continued to circulate at much lower rates in 2010. Therefore, on August 10 of 2010 the WHO declared the end of the pandemic. Important mutations associated with host specificity, virulence, and drug resistance were detected in the pandemic virus, indicating effective transmission and increased severity in humans. Much has been learned about the evolutionary dynamics of this pandemic virus; however, it is still impossible to predict when the next pandemic will occur and which virus will be responsible. Improved surveillance at different levels (both national and international) and in different hosts (especially in swine) appears to be crucial for early detection and prevention of future influenza pandemics.


Subject(s)
Biological Evolution , Influenza A Virus, H1N1 Subtype/genetics , Influenza, Human/epidemiology , Influenza, Human/virology , Orthomyxoviridae Infections/veterinary , Pandemics , Animals , Humans , Orthomyxoviridae Infections/epidemiology , Orthomyxoviridae Infections/virology , Population Surveillance
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