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1.
Genome Res ; 32(1): 124-134, 2022 01.
Article in English | MEDLINE | ID: mdl-34876496

ABSTRACT

Current understandings of individual disease etiology and therapeutics are limited despite great need. To fill the gap, we propose a novel computational pipeline that collects potent disease gene cooperative pathways to envision individualized disease etiology and therapies. Our algorithm constructs individualized disease modules de novo, which enables us to elucidate the importance of mutated genes in specific patients and to understand the synthetic penetrance of these genes across patients. We reveal that importance of the notorious cancer drivers TP53 and PIK3CA fluctuate widely across breast cancers and peak in tumors with distinct numbers of mutations and that rarely mutated genes such as XPO1 and PLEKHA1 have high disease module importance in specific individuals. Furthermore, individualized module disruption enables us to devise customized singular and combinatorial target therapies that were highly varied across patients, showing the need for precision therapeutics pipelines. As the first analysis of de novo individualized disease modules, we illustrate the power of individualized disease modules for precision medicine by providing deep novel insights on the activity of diseased genes in individuals.


Subject(s)
Breast Neoplasms , Precision Medicine , Algorithms , Breast Neoplasms/genetics , Breast Neoplasms/therapy , Female , Humans , Mutation , Penetrance
2.
J Infect Dis ; 229(2): 473-484, 2024 Feb 14.
Article in English | MEDLINE | ID: mdl-37786979

ABSTRACT

Despite intensive characterization of immune responses after COVID-19 infection and vaccination, research examining protective correlates of vertical transmission in pregnancy are limited. Herein, we profiled humoral and cellular characteristics in pregnant women infected or vaccinated at different trimesters and in their corresponding newborns. We noted a significant correlation between spike S1-specific IgG antibody and its RBD-ACE2 blocking activity (receptor-binding domain-human angiotensin-converting enzyme 2) in maternal and cord plasma (P < .001, R > 0.90). Blocking activity of spike S1-specific IgG was significantly higher in pregnant women infected during the third trimester than the first and second trimesters. Elevated levels of 28 cytokines/chemokines, mainly proinflammatory, were noted in maternal plasma with infection at delivery, while cord plasma with maternal infection 2 weeks before delivery exhibited the emergence of anti-inflammatory cytokines. Our data support vertical transmission of protective SARS-CoV-2-specific antibodies. This vertical antibody transmission and the presence of anti-inflammatory cytokines in cord blood may offset adverse outcomes of inflammation in exposed newborns.


Subject(s)
COVID-19 , Pregnancy Complications, Infectious , Infant, Newborn , Pregnancy , Humans , Female , SARS-CoV-2 , Antibodies, Viral , Cytokines , Anti-Inflammatory Agents
3.
Arch Virol ; 168(12): 299, 2023 Nov 28.
Article in English | MEDLINE | ID: mdl-38015274

ABSTRACT

This brief report presents the findings of an epidemiological investigation into a large-scale outbreak of norovirus gastroenteritis that occurred in a hotel in Algarve, Portugal, in August 2022. A total of 244 cases were reported, primarily affecting Portuguese families, with the parents aged 40-50 years and the children aged 0-19 years. Reported symptoms included vomiting, nausea, abdominal pain, and diarrhoea. Norovirus genotype GI.3 [P3] was detected in stool samples from eight probable cases, while food samples tested negative for norovirus and common pathogenic bacteria. The investigation data collected suggest that the source of the outbreak was likely in the hotel's common areas, with subsequent person-to-person transmission in other areas. The final report emphasizes the importance of improving outbreak prevention and control measures, including the development of a foodborne outbreak investigation protocol, the establishment of an outbreak response team, and the enhancement of regional laboratory capacity.


Subject(s)
Norovirus , Child , Humans , Norovirus/genetics , Disease Outbreaks , Diarrhea , Portugal/epidemiology , Vomiting
4.
PLoS Pathog ; 16(10): e1008906, 2020 10.
Article in English | MEDLINE | ID: mdl-33075109

ABSTRACT

Eradication of HIV-1 by the "kick and kill" strategy requires reactivation of latent virus to cause death of infected cells by either HIV-induced or immune-mediated apoptosis. To date this strategy has been unsuccessful, possibly due to insufficient cell death in reactivated cells to effectively reduce HIV-1 reservoir size. As a possible cause for this cell death resistance, we examined whether leading latency reversal agents (LRAs) affected apoptosis sensitivity of CD4 T cells. Multiple LRAs of different classes inhibited apoptosis in CD4 T cells. Protein kinase C (PKC) agonists bryostatin-1 and prostratin induced phosphorylation and enhanced neutralizing capability of the anti-apoptotic protein BCL2 in a PKC-dependent manner, leading to resistance to apoptosis induced by both intrinsic and extrinsic death stimuli. Furthermore, HIV-1 producing CD4 T cells expressed more BCL2 than uninfected cells, both in vivo and after ex vivo reactivation. Therefore, activation of BCL2 likely contributes to HIV-1 persistence after latency reversal with PKC agonists. The effects of LRAs on apoptosis sensitivity should be considered in designing HIV cure strategies predicated upon the "kick and kill" paradigm.


Subject(s)
Apoptosis/drug effects , HIV Infections/virology , HIV-1/pathogenicity , Protein Kinase C/chemistry , Virus Latency/drug effects , CD4-Positive T-Lymphocytes/virology , HIV Infections/drug therapy , Humans , Phosphorylation , Protein Kinase C/metabolism , Proto-Oncogene Proteins c-bcl-2/metabolism , Virus Activation/drug effects , bcl-Associated Death Protein/metabolism
5.
Mol Cell ; 53(3): 369-79, 2014 Feb 06.
Article in English | MEDLINE | ID: mdl-24462115

ABSTRACT

Nitric oxide (NO) is an important signaling compound in prokaryotes and eukaryotes. In plants, NO regulates critical developmental transitions and stress responses. Here, we identify a mechanism for NO sensing that coordinates responses throughout development based on targeted degradation of plant-specific transcriptional regulators, the group VII ethylene response factors (ERFs). We show that the N-end rule pathway of targeted proteolysis targets these proteins for destruction in the presence of NO, and we establish them as critical regulators of diverse NO-regulated processes, including seed germination, stomatal closure, and hypocotyl elongation. Furthermore, we define the molecular mechanism for NO control of germination and crosstalk with abscisic acid (ABA) signaling through ERF-regulated expression of ABSCISIC ACID INSENSITIVE5 (ABI5). Our work demonstrates how NO sensing is integrated across multiple physiological processes by direct modulation of transcription factor stability and identifies group VII ERFs as central hubs for the perception of gaseous signals in plants.


Subject(s)
Arabidopsis Proteins/metabolism , Nitric Oxide/metabolism , Transcription Factors/metabolism , Abscisic Acid/metabolism , Arabidopsis Proteins/drug effects , Arabidopsis Proteins/genetics , Basic-Leucine Zipper Transcription Factors/genetics , Basic-Leucine Zipper Transcription Factors/metabolism , Gene Expression Regulation, Plant/drug effects , Germination/drug effects , Germination/physiology , Nitric Oxide/pharmacology , Oxygen/pharmacology , Plant Stomata/drug effects , Proteolysis , Signal Transduction , Transcription Factors/drug effects
6.
7.
Nucleic Acids Res ; 47(14): e82, 2019 08 22.
Article in English | MEDLINE | ID: mdl-31114928

ABSTRACT

With the emergence of genome editing technologies and synthetic biology, it is now possible to engineer genetic circuits driving a cell's phenotypic response to a stressor. However, capturing a continuous response, rather than simply a binary 'on' or 'off' response, remains a bioengineering challenge. No tools currently exist to identify gene candidates responsible for predetermining and fine-tuning cell response phenotypes. To address this gap, we devised a novel Regulostat Inferelator (RSI) algorithm to decipher intrinsic molecular devices or networks that predetermine cellular phenotypic responses. The RSI algorithm is designed to extract gene expression patterns from basal transcriptomic data in order to identify 'regulostat' constituent gene pairs, which exhibit rheostat-like mode-of-cooperation capable of fine-tuning cellular response. Our proof-of-concept study provides computational evidence for the existence of regulostats and that these networks predetermine cellular response prior to exposure to a stressor or drug. In addition, our work, for the first time, provides evidence of context-specific, drug-regulostat interactions in predetermining drug response phenotypes in cancer cells. Given RSI-inferred regulostat networks offer insights for prioritizing gene candidates capable of rendering a resistant phenotype sensitive to a given drug, we envision that this tool will be of great value in bioengineering and medicine.


Subject(s)
Algorithms , Computational Biology/methods , Gene Expression Profiling/methods , Gene Expression Regulation , Gene Regulatory Networks/genetics , Cell Line, Tumor , Computer Simulation , Humans , Phenotype
8.
Neurosurg Focus ; 50(2): E10, 2021 02.
Article in English | MEDLINE | ID: mdl-33524942

ABSTRACT

Oncolytic viruses (OVs) are a class of immunotherapeutic agents with promising preclinical results for the treatment of glioblastoma (GBM) but have shown limited success in recent clinical trials. Advanced bioengineering principles from disciplines such as synthetic and systems biology are needed to overcome the current challenges faced in developing effective OV-based immunotherapies for GBMs, including off-target effects and poor clinical responses. Synthetic biology is an emerging field that focuses on the development of synthetic DNA constructs that encode networks of genes and proteins (synthetic genetic circuits) to perform novel functions, whereas systems biology is an analytical framework that enables the study of complex interactions between host pathways and these synthetic genetic circuits. In this review, the authors summarize synthetic and systems biology concepts for developing programmable, logic-based OVs to treat GBMs. Programmable OVs can increase selectivity for tumor cells and enhance the local immunological response using synthetic genetic circuits. The authors discuss key principles for developing programmable OV-based immunotherapies, including how to 1) select an appropriate chassis, a vector that carries a synthetic genetic circuit, and 2) design a synthetic genetic circuit that can be programmed to sense key signals in the GBM microenvironment and trigger release of a therapeutic payload. To illustrate these principles, some original laboratory data are included, highlighting the need for systems biology studies, as well as some preliminary network analyses in preparation for synthetic biology applications. Examples from the literature of state-of-the-art synthetic genetic circuits that can be packaged into leading candidate OV chassis are also surveyed and discussed.


Subject(s)
Glioblastoma , Oncolytic Virotherapy , Oncolytic Viruses , Glioblastoma/genetics , Glioblastoma/therapy , Humans , Immunotherapy , Oncolytic Viruses/genetics , Systems Biology , Tumor Microenvironment
9.
Eur J Clin Microbiol Infect Dis ; 39(9): 1761-1770, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32494956

ABSTRACT

Neisseria gonorrhoeae antimicrobial resistance (AMR) and gonorrhea disease burden remain major public health concerns worldwide. To contribute to the supranational demands to monitor and manage the spread of antimicrobial-resistant N. gonorrhoeae, the Portuguese NIH promoted the creation of the National Laboratory Network for Neisseria gonorrhoeae Collection (PTGonoNet). The present study reports the N. gonorrhoeae major AMR trends observed from 2003 up to 2018. All isolates described in the present study constitute the opportunistic ongoing N. gonorrhoeae isolate collection supported by the National Reference Laboratory for Sexually Transmitted Infections of the Portuguese NIH, enrolling strains isolated in 35 different public and private laboratories. Minimum inhibitory concentrations were determined using E-tests for azithromycin, benzylpenicillin, cefixime, ceftriaxone, ciprofloxacin, gentamicin, spectinomycin and tetracycline. Molecular typing was determined using NG-MAST. AMR data of 2596 country-spread isolates show that 87.67% of all N. gonorrhoeae isolates presented decreased susceptibility to at least one antimicrobial. A continuous decreased susceptibility and resistance to penicillin, tetracycline and ciprofloxacin can be observed along the years. However, no decreased susceptibility to cephalosporins was observed until 2018, while for azithromycin, this was always low. The most common observed NG-MAST genogroups were G1407, G7445, G225, G2, and G1034. This study evidences the advantages of a nationwide collection of isolates and of centralized AMR testing to respond to supranational (EURO-GASP) requirements while providing unprecedented data on AMR in the context of 15 years of surveillance.


Subject(s)
Anti-Bacterial Agents/pharmacology , Gonorrhea/epidemiology , Neisseria gonorrhoeae/isolation & purification , Adolescent , Adult , Child , Demography , Drug Resistance, Bacterial , Female , Gonorrhea/drug therapy , Gonorrhea/microbiology , Humans , Male , Microbial Sensitivity Tests , Middle Aged , Molecular Epidemiology , Neisseria gonorrhoeae/drug effects , Neisseria gonorrhoeae/genetics , Portugal/epidemiology , Specimen Handling , Young Adult
10.
J Stroke Cerebrovasc Dis ; 29(4): 104691, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32067853

ABSTRACT

BACKGROUND AND PURPOSE: Acute ischemic stroke (AIS) severity and clinical course are less known in direct oral anticoagulants (DOAC) users. We aimed to explore the outcome of AIS in patients pretreated with vitamin-K-antagonists (VKA) and DOAC. METHODS: A retrospective study was performed. Patients pretreated with oral anticoagulants (OAC) for nonvalvular atrial fibrillation admitted for AIS in a stroke unit between 2016-01-01 and 2018-08-31 were included. The primary endpoint was mortality during the hospital stay, and secondary endpoints were neurologic improvement at stroke unit discharge and good functional outcome 90 days after AIS. RESULTS: A total of 156 patients were included (83 on VKA and 73 on DOAC). Stroke severity (defined by NIHSS on admission) was comparable in both groups (AVK 13.0 [4.0-20.0] versus DOAC 11.0 [4.0-17.0], P = .435). Infratherapeutic levels and/or inappropriate low dose of OAC was also similar between groups (P = .152) and was not associated with stroke severity (P = .631) or mortality (P = .788). VKA (OR 12.616, P = .035, 95%CI 1.19-133.64) and PH2 hemorrhagic transformation (OR 7.516, P = .024, 95%CI 1.31-43.20) were associated with higher mortality in multivariate analysis. Higher stroke severity (OR .101, P < .001, 95%CI .037-.279) and VKA usage (OR .212, P = .003, 95%CI .08-.58) were associated with worse functional outcome at 3 months. Reperfusion therapy was significantly associated with neurologic improvement during stroke unit stay (OR 3.969, P = .009, 95%CI 1.42-11.11) but not with the functional outcome (P = .063). CONCLUSIONS: Nonvalvular atrial fibrillation patients pretreated with DOAC admitted for AIS had a better outcome when compared to VKA, although stroke severity was similar between groups.


Subject(s)
Anticoagulants/administration & dosage , Antithrombins/administration & dosage , Atrial Fibrillation/drug therapy , Brain Ischemia/etiology , Stroke/etiology , Vitamin K/antagonists & inhibitors , Administration, Oral , Aged , Aged, 80 and over , Anticoagulants/adverse effects , Antithrombins/adverse effects , Atrial Fibrillation/complications , Atrial Fibrillation/diagnosis , Brain Ischemia/diagnosis , Brain Ischemia/mortality , Brain Ischemia/therapy , Disability Evaluation , Female , Hospital Mortality , Humans , Male , Recovery of Function , Retrospective Studies , Risk Assessment , Risk Factors , Severity of Illness Index , Stroke/diagnosis , Stroke/mortality , Stroke/therapy , Time Factors , Treatment Outcome
11.
Nucleic Acids Res ; 44(10): e100, 2016 06 02.
Article in English | MEDLINE | ID: mdl-26975659

ABSTRACT

The sequential chain of interactions altering the binary state of a biomolecule represents the 'information flow' within a cellular network that determines phenotypic properties. Given the lack of computational tools to dissect context-dependent networks and gene activities, we developed NetDecoder, a network biology platform that models context-dependent information flows using pairwise phenotypic comparative analyses of protein-protein interactions. Using breast cancer, dyslipidemia and Alzheimer's disease as case studies, we demonstrate NetDecoder dissects subnetworks to identify key players significantly impacting cell behaviour specific to a given disease context. We further show genes residing in disease-specific subnetworks are enriched in disease-related signalling pathways and information flow profiles, which drive the resulting disease phenotypes. We also devise a novel scoring scheme to quantify key genes-network routers, which influence many genes, key targets, which are influenced by many genes, and high impact genes, which experience a significant change in regulation. We show the robustness of our results against parameter changes. Our network biology platform includes freely available source code (http://www.NetDecoder.org) for researchers to explore genome-wide context-dependent information flow profiles and key genes, given a set of genes of particular interest and transcriptome data. More importantly, NetDecoder will enable researchers to uncover context-dependent drug targets.


Subject(s)
Computational Biology/methods , Protein Interaction Maps , Software , Transcriptome , Algorithms , Alzheimer Disease/genetics , Alzheimer Disease/metabolism , Breast Neoplasms/genetics , Breast Neoplasms/metabolism , Databases, Factual , Dyslipidemias/genetics , Dyslipidemias/metabolism , Female , Gene Regulatory Networks , Humans , Signal Transduction
12.
Proc Natl Acad Sci U S A ; 112(32): 9860-5, 2015 Aug 11.
Article in English | MEDLINE | ID: mdl-26216971

ABSTRACT

Antibody-based therapeutics have now had success in the clinic. The affinity and specificity of the antibody for the target ligand determines the specificity of therapeutic delivery and off-target side effects. The discovery and optimization of high-affinity antibodies to important therapeutic targets could be significantly improved by the availability of a robust, eukaryotic display technology comparable to phage display that would overcome the protein translation limitations of microorganisms. The use of eukaryotic cells would improve the diversity of the displayed antibodies that can be screened and optimized as well as more seamlessly transition into a large-scale mammalian expression system for clinical production. In this study, we demonstrate that the replication and polypeptide display characteristics of a eukaryotic retrovirus, avian leukosis virus (ALV), offers a robust, eukaryotic version of bacteriophage display. The binding affinity of a model single-chain Fv antibody was optimized by using ALV display, improving affinity >2,000-fold, from micromolar to picomolar levels. We believe ALV display provides an extension to antibody display on microorganisms and offers virus and cell display platforms in a eukaryotic expression system. ALV display should enable an improvement in the diversity of properly processed and functional antibody variants that can be screened and affinity-optimized to improve promising antibody candidates.


Subject(s)
Antibodies/metabolism , Avian Leukosis Virus/metabolism , Cell Surface Display Techniques/methods , Eukaryotic Cells/metabolism , Amino Acid Sequence , Animals , Cell Line , Chickens , Complementarity Determining Regions , Glycoproteins/metabolism , Humans , Kinetics , Laminin/metabolism , Molecular Sequence Data , Mutagenesis , Mutant Proteins/chemistry , Mutant Proteins/metabolism , Protein Binding , Recombinant Fusion Proteins/metabolism , Single-Chain Antibodies/metabolism , Viral Envelope Proteins/metabolism , Virion/metabolism , Virus Replication
13.
Blood ; 125(4): 658-67, 2015 Jan 22.
Article in English | MEDLINE | ID: mdl-25452615

ABSTRACT

Follicular lymphoma (FL), an indolent neoplasm caused by a t(14;18) chromosomal translocation that juxtaposes the BCL2 gene and immunoglobulin locus, has a variable clinical course and frequently undergoes transformation to an aggressive lymphoma. Although BCL2 mutations have been previously described, their relationship to FL progression remains unclear. In this study, we evaluated the frequency and nature of BCL2 mutations in 2 independent cohorts of grade 1 and 2 FLs, along with the correlation between BCL2 mutations, transformation risk, and survival. The prevalence of BCL2 coding sequence mutations was 12% in FL at diagnosis and 53% at transformation (P < .0001). The presence of these BCL2 mutations at diagnosis correlated with an increased risk of transformation (hazard ratio 3.6; 95% CI, 2.0-6.2; P < .0001) and increased risk of death due to lymphoma (median survival of 9.5 years with BCL2 mutations vs 20.4 years without; P = .012). In a multivariate analysis, BCL2 mutations and high FL international prognostic index were independent risk factors for transformation and death due to lymphoma. Some mutant Bcl-2 proteins exhibited enhanced antiapoptotic capacity in vitro. Accordingly, BCL2 mutations can affect antiapoptotic Bcl-2 function, are associated with increased activation-induced cytidine deaminase expression, and correlate with increased risk of transformation and death due to lymphoma.


Subject(s)
Cell Transformation, Neoplastic/genetics , Lymphoma, Follicular/genetics , Lymphoma, Follicular/mortality , Mutation , Proto-Oncogene Proteins c-bcl-2/genetics , Adult , Age Factors , Aged , Aged, 80 and over , Cell Transformation, Neoplastic/metabolism , Cell Transformation, Neoplastic/pathology , Chromosomes, Human, Pair 14/genetics , Chromosomes, Human, Pair 14/metabolism , Chromosomes, Human, Pair 18/genetics , Chromosomes, Human, Pair 18/metabolism , Cohort Studies , Cytidine Deaminase/biosynthesis , Cytidine Deaminase/genetics , Disease-Free Survival , Female , Gene Expression Regulation, Enzymologic/genetics , Gene Expression Regulation, Neoplastic/drug effects , Humans , Immunoglobulins/genetics , Immunoglobulins/metabolism , Lymphoma, Follicular/metabolism , Male , Middle Aged , Prevalence , Proto-Oncogene Proteins c-bcl-2/metabolism , Risk Factors , Survival Rate
14.
Biomed Microdevices ; 19(4): 81, 2017 Sep 07.
Article in English | MEDLINE | ID: mdl-28884359

ABSTRACT

Microfluidics, the science of engineering fluid streams at the micrometer scale, offers unique tools for creating and controlling gradients of soluble compounds. Gradient generation can be used to recreate complex physiological microenvironments, but is also useful for screening purposes. For example, in a single experiment, adherent cells can be exposed to a range of concentrations of the compound of interest, enabling high-content analysis of cell behaviour and enhancing throughput. In this study, we present the development of a microfluidic screening platform where, by means of diffusion, gradients of soluble compounds can be generated and sustained. This platform enables the culture of adherent cells under shear stress-free conditions, and their exposure to a soluble compound in a concentration gradient-wise manner. The platform consists of five serial cell culture chambers, all coupled to two lateral fluid supply channels that are used for gradient generation through a source-sink mechanism. Furthermore, an additional inlet and outlet are used for cell seeding inside the chambers. Finite element modeling was used for the optimization of the design of the platform and for validation of the dynamics of gradient generation. Then, as a proof-of-concept, human osteosarcoma MG-63 cells were cultured inside the platform and exposed to a gradient of Cytochalasin D, an actin polymerization inhibitor. This set-up allowed us to analyze cell morphological changes over time, including cell area and eccentricity measurements, as a function of Cytochalasin D concentration by using fluorescence image-based cytometry.


Subject(s)
Cytochalasin D/pharmacology , Lab-On-A-Chip Devices , Microfluidic Analytical Techniques/methods , Optical Imaging , Osteosarcoma , Shear Strength , Cell Culture Techniques/instrumentation , Cell Culture Techniques/methods , Cell Line, Tumor , Humans , Optical Imaging/instrumentation , Optical Imaging/methods , Osteosarcoma/metabolism , Osteosarcoma/pathology
15.
Biotechnol Bioeng ; 114(4): 717-739, 2017 04.
Article in English | MEDLINE | ID: mdl-27618194

ABSTRACT

Osteoarthritis (OA) affects a large number of the population, and its incidence is showing a growing trend with the increasing life span. OA is the most prevalent joint condition worldwide, and currently, there is no functional cure for it. This review seeks to briefly overview the management of knee OA concerning standardized pharmaceutical and clinical approaches, as well as the new biotechnological horizons of OA treatment. The potential of biomaterials and state of the art of advanced therapeutic approaches, such as cell and gene therapy focused primarily on cartilage regeneration are the main subjects of this review. Biotechnol. Bioeng. 2017;114: 717-739. © 2016 Wiley Periodicals, Inc.


Subject(s)
Osteoarthritis, Knee/therapy , Biocompatible Materials , Cartilage, Articular/cytology , Cartilage, Articular/physiology , Genetic Therapy , Humans , Tissue Engineering
16.
Nature ; 479(7373): 415-8, 2011 Oct 23.
Article in English | MEDLINE | ID: mdl-22020279

ABSTRACT

Plants and animals are obligate aerobes, requiring oxygen for mitochondrial respiration and energy production. In plants, an unanticipated decline in oxygen availability (hypoxia), as caused by roots becoming waterlogged or foliage submergence, triggers changes in gene transcription and messenger RNA translation that promote anaerobic metabolism and thus sustain substrate-level ATP production. In contrast to animals, oxygen sensing has not been ascribed to a mechanism of gene regulation in response to oxygen deprivation in plants. Here we show that the N-end rule pathway of targeted proteolysis acts as a homeostatic sensor of severe low oxygen levels in Arabidopsis, through its regulation of key hypoxia-response transcription factors. We found that plants lacking components of the N-end rule pathway constitutively express core hypoxia-response genes and are more tolerant of hypoxic stress. We identify the hypoxia-associated ethylene response factor group VII transcription factors of Arabidopsis as substrates of this pathway. Regulation of these proteins by the N-end rule pathway occurs through a characteristic conserved motif at the amino terminus initiating with Met-Cys. Enhanced stability of one of these proteins, HRE2, under low oxygen conditions improves hypoxia survival and reveals a molecular mechanism for oxygen sensing in plants via the evolutionarily conserved N-end rule pathway. SUB1A-1, a major determinant of submergence tolerance in rice, was shown not to be a substrate for the N-end rule pathway despite containing the N-terminal motif, indicating that it is uncoupled from N-end rule pathway regulation, and that enhanced stability may relate to the superior tolerance of Sub1 rice varieties to multiple abiotic stresses.


Subject(s)
Arabidopsis/metabolism , Cell Hypoxia , Homeostasis , Acclimatization , Anaerobiosis/drug effects , Anaerobiosis/genetics , Arabidopsis/drug effects , Arabidopsis/genetics , Arabidopsis Proteins/metabolism , Cell Hypoxia/drug effects , Cell Hypoxia/genetics , Ethylenes/pharmacology , Floods , Gene Expression Regulation, Plant/drug effects , Homeostasis/drug effects , Immersion , Oryza/drug effects , Oryza/metabolism , Oxygen/metabolism , Oxygen/pharmacology , Proteolysis/drug effects , RNA, Messenger/genetics , RNA, Messenger/metabolism , RNA, Plant/genetics , RNA, Plant/metabolism , Transcription Factors/metabolism
17.
Biochim Biophys Acta ; 1853(7): 1658-71, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25827952

ABSTRACT

Bcl-2, the founding member of a family of apoptotic regulators, was initially identified as the protein product of a gene that is translocated and overexpressed in greater than 85% of follicular lymphomas (FLs). Thirty years later we now understand that anti-apoptotic Bcl-2 family members modulate the intrinsic apoptotic pathway by binding and neutralizing the mitochondrial permeabilizers Bax and Bak as well as a variety of pro-apoptotic proteins, including the cellular stress sensors Bim, Bid, Puma, Bad, Bmf and Noxa. Despite extensive investigation of all of these proteins, important questions remain. For example, how Bax and Bak breach the outer mitochondrial membrane remains poorly understood. Likewise, how the functions of anti-apoptotic Bcl-2 family members such as eponymous Bcl-2 are affected by phosphorylation or cancer-associated mutations has been incompletely defined. Finally, whether Bcl-2 family members can be successfully targeted for therapeutic advantage is only now being investigated in the clinic. Here we review recent advances in understanding Bcl-2 family biology and biochemistry that begin to address these questions.


Subject(s)
Disease Progression , Neoplasms/metabolism , Neoplasms/pathology , Proto-Oncogene Proteins c-bcl-2/metabolism , Amino Acid Sequence , Animals , Apoptosis , Humans , Models, Biological , Molecular Sequence Data , Molecular Targeted Therapy , Proto-Oncogene Proteins c-bcl-2/chemistry , Proto-Oncogene Proteins c-bcl-2/genetics
18.
Appl Environ Microbiol ; 81(23): 8155-63, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26386065

ABSTRACT

Meat and meat products are important sources of human intestinal infections. We report the isolation of Helicobacter pullorum strains from chicken meat. Bacteria were isolated from 4 of the 17 analyzed fresh chicken meat samples, using a membrane filter method. MIC determination revealed that the four strains showed acquired resistance to ciprofloxacin; one was also resistant to erythromycin, and another one was resistant to tetracycline. Whole-genome sequencing of the four strains and comparative genomics revealed important genetic traits within the H. pullorum species, such as 18 highly polymorphic genes (including a putative new cytotoxin gene), plasmids, prophages, and a complete type VI secretion system (T6SS). The T6SS was found in three out of the four isolates, suggesting that it may play a role in H. pullorum pathogenicity and diversity. This study suggests that the emerging pathogen H. pullorum can be transmitted to humans by chicken meat consumption/contact and constitutes an important contribution toward a better knowledge of the genetic diversity within the H. pullorum species. In addition, some genetic traits found in the four strains provide relevant clues to how this species may promote adaptation and virulence.


Subject(s)
Anti-Bacterial Agents/pharmacology , Drug Resistance, Bacterial , Food Microbiology , Genome, Bacterial , Helicobacter/drug effects , Helicobacter/genetics , Meat/microbiology , Animals , Chickens , Ciprofloxacin/pharmacology , Erythromycin/pharmacology , Helicobacter/isolation & purification , Helicobacter/pathogenicity , Microbial Sensitivity Tests , Sequence Analysis, DNA , Tetracycline/pharmacology , Virulence
19.
Drug Discov Today ; 29(1): 103825, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37967790

ABSTRACT

With increasing human life expectancy, the global medical burden of chronic diseases is growing. Hence, chronic diseases are a pressing health concern and will continue to be in decades to come. Chronic diseases often involve multiple malfunctioning organs in the body. An imminent question is how interorgan crosstalk contributes to the etiology of chronic diseases. We conceived the locked-state model (LoSM), which illustrates how interorgan communication can give rise to body-wide memory-like properties that 'lock' healthy or pathological conditions. Next, we propose cutting-edge systems biology and artificial intelligence strategies to decipher chronic multiorgan locked states. Finally, we discuss the clinical implications of the LoSM and assess the power of systems-based therapies to dismantle pathological multiorgan locked states while improving treatments for chronic diseases.


Subject(s)
Artificial Intelligence , Network Pharmacology , Humans , Life Expectancy , Chronic Disease
20.
Cancers (Basel) ; 16(4)2024 Feb 18.
Article in English | MEDLINE | ID: mdl-38398213

ABSTRACT

Cancer is a complex disease involving the deregulation of intricate cellular systems beyond genetic aberrations and, as such, requires sophisticated computational approaches and high-dimensional data for optimal interpretation. While conventional artificial intelligence (AI) models excel in many prediction tasks, they often lack interpretability and are blind to the scientific hypotheses generated by researchers to enable cancer discoveries. Here we propose that hypothesis-driven AI, a new emerging class of AI algorithm, is an innovative approach to uncovering the complex etiology of cancer from big omics data. This review exemplifies how hypothesis-driven AI is different from conventional AI by citing its application in various areas of oncology including tumor classification, patient stratification, cancer gene discovery, drug response prediction, and tumor spatial organization. Our aim is to stress the feasibility of incorporating domain knowledge and scientific hypotheses to craft the design of new AI algorithms. We showcase the power of hypothesis-driven AI in making novel cancer discoveries that can be overlooked by conventional AI methods. Since hypothesis-driven AI is still in its infancy, open questions such as how to better incorporate new knowledge and biological perspectives to ameliorate bias and improve interpretability in the design of AI algorithms still need to be addressed. In conclusion, hypothesis-driven AI holds great promise in the discovery of new mechanistic and functional insights that explain the complexity of cancer etiology and potentially chart a new roadmap to improve treatment regimens for individual patients.

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