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1.
Sultan Qaboos Univ Med J ; 24(1): 85-90, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38434468

ABSTRACT

Objectives: Inflammatory bowel disease (IBD), generally comprising Crohn's disease (CD) and ulcerative colitis (UC), has become a significant global public health concern in the last decade. This study aimed to determine the alternations in the whole genomic expression profile of patients with IBD in this geographic location for the first time, as there are very few articles in the literature addressing this specific aspect of the field. Methods: The study was conducted in Erbil Governorate in the Kurdistan region of Iraq from July 2021 to July 2022. The genome expression profiles of 10 patients with IBD were compared to their matched controls. The sequences used in the design of the array were selected from GenBank®, dbEST and RefSeq. Whole blood RNA was extracted and hybridisation was conducted on the GeneChip® human genome U133A 2.0 array. The Scanner 3000 was used to scan high-resolution images and the General Comprehensive Operating System was used to read the results. Results: The upregulated genes shared between patients with UC and CD were RIT2, BCL2L1, MDM2 and FKBP8, while the downregulated genes they shared were the NFKBIB, DDX24 and RASA3 genes. Conclusions: Upregulated and downregulated gene expression patterns were detected in individuals with IBD, offering diagnostic potential and opportunities for treatment by targeting the associated pathways.


Subject(s)
Inflammatory Bowel Diseases , Transcriptome , Humans , Iraq , Inflammatory Bowel Diseases/genetics , Patients , Public Health , DEAD-box RNA Helicases
2.
J Coll Physicians Surg Pak ; 33(12): 1367-1371, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38062590

ABSTRACT

OBJECTIVE: To compare the efficacy and safety of meglumine antimoniate and miltefosine in the treatment of cutaneous leishmaniasis in Pakistan. STUDY DESIGN: Randomised-controlled trial. Place and Duration of the Study: Department of Dermatology, Combined Military Hospital, Lahore and Peshawar, from January to December 2021. METHODOLOGY: Smear positive and/or skin biopsy-confirmed cases of cutaneous leishmaniasis in adult males aged between 18-60 years were enrolled after receiving informed consent. Patients were randomly divided into Group A and Group B by lottery method. Group A received intramuscular meglumine antimoniate 15-20mg/kg/day, and Group B received oral miltefosine 50 mg thrice a day for a duration of 28 days. Data were analysed by SPSS 22. Effectiveness and safety of therapeutic agents were calculated by Independent t-test and p-value of 0.05 or less was taken as significant. RESULTS: Sixty-six patients, 33 in each group, participated in the study. Total number of cutaneous leishmaniasis lesions were 77 in Group A and 76 in Group B. The duration of lesions was 3.5 months in Group A and 3.2 months in Group B. Treatment response, in terms of complete or near complete resolution of lesions, was significantly higher in Group A as compared to Group B (p = 0.011). Both therapeutic agents had considerable side-effects with more patients withdrawn from Group A as compared to Group B (p = 0.010). CONCLUSION: Intra-muscular meglumine antimoniate was more effective in comparison to oral miltefosine in the treatment of cutaneous leishmaniasis. However, efficacy of meglumine antimoniate is mired by its side-effect profile. KEY WORDS: Cutaneous leishmaniasis, Meglumine antimoniate, Miltefosine, Efficacy, Side-effects, Adverse effects, Safety, Treatment, Old world cutaneous leishmaniasis.


Subject(s)
Antiprotozoal Agents , Leishmaniasis, Cutaneous , Organometallic Compounds , Adult , Male , Humans , Adolescent , Young Adult , Middle Aged , Meglumine Antimoniate/therapeutic use , Antiprotozoal Agents/adverse effects , Meglumine/adverse effects , Organometallic Compounds/adverse effects , Injections, Intramuscular , Leishmaniasis, Cutaneous/drug therapy , Treatment Outcome
3.
Am J Perinatol ; 2023 Jun 19.
Article in English | MEDLINE | ID: mdl-37216975

ABSTRACT

OBJECTIVE: The objective of this study is to examine risk factors and adverse outcomes related to preeclampsia with severe features complicated by pulmonary edema. STUDY DESIGN: This is a nested case-control study of all patients with preeclampsia with severe features who delivered in a tertiary, urban, academic medical center over a 1-year period. The primary exposure was pulmonary edema and the primary outcome was a composite of severe maternal morbidity (SMM), defined according to the Centers for Disease Control and Prevention and based on International Classification of Diseases, 10th revision, Clinical Modification codes. Secondary outcomes included postpartum length of stay, maternal intensive care unit admission, 30-day readmission, and discharge on antihypertensive medication. A multivariable logistic regression model adjusting for clinical characteristics related to the primary outcome was used to determine adjusted odds ratios (aOR) as measures of effect. RESULTS: Of 340 patients with severe preeclampsia, there were seven cases of pulmonary edema (2.1%). Pulmonary edema was associated with lower parity, autoimmune disease, earlier gestational age at diagnosis of preeclampsia and at delivery, and cesarean section. Patients with pulmonary edema demonstrated increased odds of SMM (aOR: 10.11, 95% confidence interval [CI]: 2.13-47.90), extended postpartum length of stay (aOR: 32.56, 95% CI: 3.95-268.45), and intensive care unit admission (aOR: 102.85, 95% CI: 7.43-1422.92) compared with those without pulmonary edema. CONCLUSION: Pulmonary edema is associated with adverse maternal outcomes among patients with severe preeclampsia, and is more likely to affect patients who are nulliparous, have an autoimmune disease, and are diagnosed preterm. KEY POINTS: · Pulmonary edema increases odds of severe maternal morbidity in preeclamptics.. · Pulmonary edema prolongs postpartum and intensive care unit stay in preeclamptics.. · Risk factors for pulmonary edema include nulliparity and autoimmune disease.. · Earlier diagnosis of severe preeclampsia increases risk of pulmonary edema..

5.
Exp Gerontol ; 167: 111908, 2022 10 01.
Article in English | MEDLINE | ID: mdl-35932934

ABSTRACT

Aging is a process that occurs in tissues and across species, leading to the degradation of many biological processes. We previously demonstrated that rabbits are a feasible model for studying aging due to their genetic homology and relatively short lifespan in comparison to humans. We utilized a cPILOT multiplexing strategy to identify proteomic changes in spleen tissues of young, middle, and old aged rabbits. We identified 63 proteins that change significantly (p < 0.05) with age and notably these proteins relate to nucleotide and RNA binding, DNA repair, actin regulation, and immune system pathways. Here, we explore the implications of aging in the spleen and demonstrate the utility of a rabbit model to understand aging processes.


Subject(s)
Proteomics , Spleen , Aging/metabolism , Animals , Humans , Longevity , Proteins , Rabbits
6.
J Med Ethics ; 2021 Jan 29.
Article in English | MEDLINE | ID: mdl-33514636

ABSTRACT

Migrant workers in dormitories are an attractive source of clinical trial participants. However, they are a vulnerable population that has been disproportionately affected by the COVID-19 pandemic. Guidelines on recruiting vulnerable populations (such as prisoners, children or the mentally impaired) for clinical trials have long been established, but ethical considerations for migrant workers have been neglected. This article aims to highlight and explain what researchers recruiting migrant workers must be cognizant of, and offers recommendations to address potential concerns. The considerations raised in this article include: three types of illiteracy, power dynamics, the risks associated with communal living and potential benefits to the migrant workers as well as researchers.

7.
Cureus ; 13(11): e19656, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34976452

ABSTRACT

Gestational trophoblastic diseases, which include molar pregnancy, have an increased risk of complications associated with the thyroid gland. This condition is mainly caused by elevated levels of beta-human chorionic gonadotropin produced during pregnancy, which is exaggerated in molar pregnancy and can lead to thyrotoxicosis. Hence, it is important to recognize the signs and symptoms of hyperthyroidism among women of childbearing age to prevent complications such as thyroid storm. Medical management of thyroid storm before surgery is critical to prevent adverse maternal outcomes. Here, we report a rare case of impending thyroid storm induced by molar pregnancy.

8.
Data Brief ; 31: 105701, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32490075

ABSTRACT

Here, we present a proteomics dataset of liver proteins to understand aging in rabbits, which complements the publication "Quantitative proteomics to study aging in rabbit liver" [1]. This dataset was generated to understand the molecular basis and metabolic changes of aging processes in liver, which is the main organ involved in metabolism, detoxification, transport, and signaling. Proteins from young, middle, and old age rabbits were extracted and digested. Generated peptides were labeled with light or heavy dimethyl groups at their N-termini, while lysine amines were labeled with TMT10-plex using a cPILOT workflow [2]. Labeled peptides were fractionated by basic pH reverse phase chromatography and analyzed with online reverse phase LC coupled with tandem mass spectrometry (MS/MS and MS3). The RAW files were generated using a Fusion Lumos Orbitrap mass spectrometer (Thermo Scientific) and processed with Proteome Discoverer (PD) version 2.2 to generate a list of identified and quantified proteins. Data was searched against the Rabbit UniProtKB redundant database. A total of 3,867 proteins were identified corresponding to 2,586 protein groups and 22,229 peptides. Dynamic levels of age-related proteins associated with fat metabolism, mitochondrial dysfunction, and protein degradation were detected. The mass spectrometry proteomics data (RAW files) and processed Proteome Discoverer 2.2 files (MSF files) have been deposited to the Proteomics Identification Database (PRIDE) ProteomeXchange Consortium and can be accessed with the dataset identifier PDX013220 (http://www.ebi.ac.uk/pride/archive/projects/PXD013220).

9.
Mech Ageing Dev ; 187: 111227, 2020 04.
Article in English | MEDLINE | ID: mdl-32126221

ABSTRACT

Aging globally effects cellular and organismal metabolism across a range of mammalian species, including humans and rabbits. Rabbits (Oryctolagus cuniculus are an attractive model system of aging due to their genetic similarity with humans and their short lifespans. This model can be used to understand metabolic changes in aging especially in major organs such as liver where we detected pronounced variations in fat metabolism, mitochondrial dysfunction, and protein degradation. Such changes in the liver are consistent across several mammalian species however in rabbits the downstream effects of these changes have not yet been explored. We have applied proteomics to study changes in the liver proteins from young, middle, and old age rabbits using a multiplexing cPILOT strategy. This resulted in the identification of 2,586 liver proteins, among which 45 proteins had significant p < 0.05) changes with aging. Seven proteins were differentially-expressed at all ages and include fatty acid binding protein, aldehyde dehydrogenase, enoyl-CoA hydratase, 3-hydroxyacyl CoA dehydrogenase, apolipoprotein C3, peroxisomal sarcosine oxidase, adhesion G-protein coupled receptor, and glutamate ionotropic receptor kinate. Insights to how alterations in metabolism affect protein expression in liver have been gained and demonstrate the utility of rabbit as a model of aging.


Subject(s)
Aging/metabolism , Gene Expression Regulation , Liver/metabolism , Models, Biological , Proteome/biosynthesis , Proteomics , Aging/genetics , Animals , Male , Rabbits
10.
Mol Cell Proteomics ; 18(4): 669-685, 2019 04.
Article in English | MEDLINE | ID: mdl-30635358

ABSTRACT

Immune sensing of Mycobacterium tuberculosis relies on recognition by macrophages. Mycobacterial cord factor, trehalose-6,6'-dimycolate (TDM), is the most abundant cell wall glycolipid and binds to the C-type lectin receptor (CLR) MINCLE. To explore the kinase signaling linking the TDM-MINCLE interaction to gene expression, we employed quantitative phosphoproteome analysis. TDM caused upregulation of 6.7% and suppressed 3.8% of the 14,000 phospho-sites identified on 3727 proteins. MINCLE-dependent phosphorylation was observed for canonical players of CLR signaling (e.g. PLCγ, PKCδ), and was enriched for PKCδ and GSK3 kinase motifs. MINCLE-dependent activation of the PI3K-AKT-GSK3 pathway contributed to inflammatory gene expression and required the PI3K regulatory subunit p85α. Unexpectedly, a substantial fraction of TDM-induced phosphorylation was MINCLE-independent, a finding paralleled by transcriptome data. Bioinformatics analysis of both data sets concurred in the requirement for MINCLE for innate immune response pathways and processes. In contrast, MINCLE-independent phosphorylation and transcriptome responses were linked to cell cycle regulation. Collectively, our global analyses show substantial reprogramming of macrophages by TDM and reveal a dichotomy of MINCLE-dependent and -independent signaling linked to distinct biological responses.


Subject(s)
Cord Factors/metabolism , Lectins, C-Type/metabolism , Macrophages/metabolism , Membrane Proteins/metabolism , Phosphoproteins/metabolism , Proteome/metabolism , Proteomics , Signal Transduction , Animals , Cell Cycle/genetics , Cell Proliferation/genetics , Cell Survival/genetics , Cord Factors/pharmacology , Cytokines/metabolism , Enzyme Activation/drug effects , Gene Expression Regulation/drug effects , Glycolipids/metabolism , Kinetics , Macrophage Activation/drug effects , Macrophage Activation/genetics , Macrophages/drug effects , Mice, Inbred C57BL , Mitogen-Activated Protein Kinases/metabolism , Mycobacterium tuberculosis/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Phosphorylation/drug effects , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction/drug effects , Syk Kinase/metabolism , Transcriptome/genetics , Trehalose/metabolism
11.
Proteomes ; 6(2)2018 Apr 17.
Article in English | MEDLINE | ID: mdl-29673200

ABSTRACT

Corynebacterium ulcerans is an emerging pathogen, which is increasingly recognized as an etiological agent of diphtheria, but can also evoke ulcers of the skin and systemic infections in humans. Besides man, the bacteria can colonize a wide variety of different animals, including cattle and pet animals, which might serve as a reservoir for human infections. In this study, surface-located proteins and the exoproteome of two Corynebacterium ulcerans strains were analyzed, since these may have key roles in the interaction of the pathogen with host cells. Strain 809 was isolated from a fatal case of human respiratory tract infection, while strain BR-AD22 was isolated from a nasal swap of an asymptomatic dog. While a very similar pattern of virulence factors was observed in the culture supernatant and surface protein fractions of the two strains, proteome analyses revealed a higher stability of 809 cells compared to strain BR-AD22. During exponential growth, 17% of encoded proteins of strain 809 were detectable in the medium, while 38% of the predicted proteins encoded by the BR-AD22 chromosome were found. Furthermore, the data indicate differential expression of phospholipase D and a cell wall-associated hydrolase, since these were only detected in strain BR-AD22.

12.
J Gen Virol ; 98(10): 2569-2581, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28949903

ABSTRACT

Nuclear egress of herpesvirus capsids is mediated by a multi-component nuclear egress complex (NEC) assembled by a heterodimer of two essential viral core egress proteins. In the case of human cytomegalovirus (HCMV), this core NEC is defined by the interaction between the membrane-anchored pUL50 and its nuclear cofactor, pUL53. NEC protein phosphorylation is considered to be an important regulatory step, so this study focused on the respective role of viral and cellular protein kinases. Multiply phosphorylated pUL50 varieties were detected by Western blot and Phos-tag analyses as resulting from both viral and cellular kinase activities. In vitro kinase analyses demonstrated that pUL50 is a substrate of both PKCα and CDK1, while pUL53 can also be moderately phosphorylated by CDK1. The use of kinase inhibitors further illustrated the importance of distinct kinases for core NEC phosphorylation. Importantly, mass spectrometry-based proteomic analyses identified five major and nine minor sites of pUL50 phosphorylation. The functional relevance of core NEC phosphorylation was confirmed by various experimental settings, including kinase knock-down/knock-out and confocal imaging, in which it was found that (i) HCMV core NEC proteins are not phosphorylated solely by viral pUL97, but also by cellular kinases; (ii) both PKC and CDK1 phosphorylation are detectable for pUL50; (iii) no impact of PKC phosphorylation on NEC functionality has been identified so far; (iv) nonetheless, CDK1-specific phosphorylation appears to be required for functional core NEC interaction. In summary, our findings provide the first evidence that the HCMV core NEC is phosphorylated by cellular kinases, and that the complex pattern of NEC phosphorylation has functional relevance.


Subject(s)
Cyclin-Dependent Kinases/metabolism , Cytomegalovirus/metabolism , Protein Kinase C-alpha/metabolism , Viral Proteins/metabolism , Virus Release/physiology , Active Transport, Cell Nucleus , CDC2 Protein Kinase , Cell Nucleus/metabolism , Cyclin-Dependent Kinases/antagonists & inhibitors , Humans , Mass Spectrometry , Phosphorylation , Protein Kinase C-alpha/antagonists & inhibitors , Protein Kinase C-alpha/genetics
13.
Prog Chem Org Nat Prod ; 106: 203-240, 2017.
Article in English | MEDLINE | ID: mdl-28762090

ABSTRACT

Peptidylarginine deiminase (PAD) enzymes are of enormous interest in biomedicine. They catalyze the conversion of a positively-charged guanidinium at an arginine side chain into a neutral ureido group. As a result of this conversion, proteins acquire the non-ribosomally encoded amino acid "citrulline". This imposes critical influences on the structure and function of the target molecules. In multiple sclerosis, myelin hyper-citrullination promotes demyelination by reducing its compaction and triggers auto-antibody production. Immune responses to citrulline-containing proteins play a central role in the pathogenesis of autoimmune diseases. Moreover, auto-antibodies, specific to citrullinated proteins, such as collagen type I and II and filaggrin, are early detectable in rheumatoid arthritis, serving as diagnostic markers of the disease. Despite their significance, little is understood about the role in demyelinating disorders, diversified cancers, and auto-immune diseases. To impart their biological and pathological effects, it is crucial to better understand the reaction mechanism, kinetic properties, substrate selection, and specificities of peptidylarginine deiminase isoforms.Many aspects of PAD biochemistry and physiology have been ignored in past, but, herein is presented a comprehensive survey to improve our current understandings of the underlying mechanism and regulation of PAD enzymes.


Subject(s)
Autoimmune Diseases/enzymology , Hydrolases/metabolism , Arthritis, Rheumatoid , Filaggrin Proteins , Humans , Protein Isoforms , Protein-Arginine Deiminases , Substrate Specificity
14.
Adv Exp Med Biol ; 974: 21-48, 2017.
Article in English | MEDLINE | ID: mdl-28353223

ABSTRACT

Biomarker research for Alzheimer's disease (AD) has been growing rapidly over recent years especially as the number of persons affected by this disease is nearing approximately 46 million worldwide. Single biomarker assays are challenging to establish since AD is multifactorial and complex. In addition to the classic signs of diminished cognition and memory, AD patients can also exhibit symptoms which may be confused with some psychiatric disorders, such as depression. No molecular biomarkers have been established or translated into clinical tools although recent efforts have resulted in addition of molecular biomarker profiles to the National Institute of Neurological and Communicative Disorders and Stroke and Alzheimer's Disease and Related Disorders Association criteria for research purposes. The three accepted molecular biomarkers are amyloid-ßeta peptide 1-42, total tau protein and hyperphosphorylated tau at threonine 181 in human cerebrospinal fluid (CSF). Aside from these three CSF markers, a number of potential candidates have been identified in CSF and other body fluids. In order to identify biomarkers for diagnosis, early prevention, prognosis and response to therapeutic treatment, multiplex biomarker tests will be required. These include multiplex immunoassay and mass spectrometry-based proteomics platforms. Proteomics analyses of bodily fluids such as plasma are growing in number and providing potential targets for further investigation and validation in AD research. This chapter highlights proteomic biomarker assays and their applications and potential use for clinical diagnosis and prognosis of AD.


Subject(s)
Alzheimer Disease/diagnosis , Biomarkers/analysis , Proteomics/methods , Alzheimer Disease/epidemiology , Alzheimer Disease/metabolism , Alzheimer Disease/psychology , Blood Proteins/analysis , Body Fluids/chemistry , Cerebrospinal Fluid Proteins/analysis , Electrophoresis, Gel, Two-Dimensional , Humans , Immunoassay/methods , Mass Spectrometry/methods , Nerve Tissue Proteins/analysis , Risk Factors , Sensitivity and Specificity , Symptom Assessment
15.
Cell Microbiol ; 19(1)2017 01.
Article in English | MEDLINE | ID: mdl-27328359

ABSTRACT

The obligate intracellular bacterium Coxiella burnetii causes the zoonotic disease Q-fever. Coxiella pathogenesis depends on a functional type IV secretion system (T4SS). The T4SS effector AnkG inhibits pathogen-induced host cell apoptosis, which is believed to be important for the establishment of a persistent infection. However, the mode of action of AnkG is not fully understood. We have previously demonstrated that binding of AnkG to p32 is crucial for migration of AnkG into the nucleus and that nuclear localization of AnkG is essential for its anti-apoptotic activity. Here, we compared the activity of AnkG from the C. burnetii strains Nine Mile and Dugway. Although there is only a single amino acid exchange at residue 11, we observed a difference in anti-apoptotic activity and nuclear migration. Mutation of amino acid 11 to glutamic acid, threonine or valine results in AnkG mutants that had lost the anti-apoptotic activity and the ability to migrate into the nucleus. We identified Importin-α1 to bind to AnkG, but not to the mutants and concluded that binding of AnkG to p32 and Importin-α1 is essential for migration into the nucleus. Also during Coxiella infection binding of AnkG to p32 and Importin-α1 is crucial for nuclear localization of AnkG.


Subject(s)
Bacterial Proteins/metabolism , Carrier Proteins/metabolism , Coxiella burnetii/physiology , Host-Pathogen Interactions , Mitochondrial Proteins/metabolism , Virulence Factors/metabolism , alpha Karyopherins/metabolism , Active Transport, Cell Nucleus , Amino Acid Substitution , Bacterial Proteins/genetics , Cell Line , DNA Mutational Analysis , Humans , Protein Binding , Virulence Factors/genetics
16.
Virus Res ; 227: 6-14, 2017 01 02.
Article in English | MEDLINE | ID: mdl-27693920

ABSTRACT

Stress granules (SGs) are structures within cells that regulate gene expression during stress response, e.g. viral infection. In mammalian cells assembly of SGs is dependent on the Ras-GAP SH3-domain-binding protein (G3BP). The C-terminal domain of the viral nonstructural protein 3 (nsP3) of Semliki Forest virus (SFV) forms a complex with mammalian G3BP and sequesters it into viral RNA replication complexes in a manner that inhibits the formation of SGs. The binding domain of nsP3 to HsG3BP was mapped to two tandem 'FGDF' repeat motifs close to the C-terminus of the viral proteins. It was speculated that plant viruses employ a similar strategy to inhibit SG function. This study identifies an Arabidopsis thaliana NTF2-RRM domain-containing protein as a G3BP-like protein (AtG3BP), which localizes to plant SGs. Moreover, the nuclear shuttle protein (NSP) of the begomovirus abutilon mosaic virus (AbMV), which harbors a 'FVSF'-motif at its C-terminal end, interacts with the AtG3BP-like protein, as does the 'FNGSF'-motif containing NSP of pea necrotic yellow dwarf virus (PNYDV), a member of the Nanoviridae family. We therefore propose that SG formation upon stress is conserved between mammalian and plant cells and that plant viruses may follow a similar strategy to inhibit plant SG function as it has been shown for their mammalian counterparts.


Subject(s)
Geminiviridae/physiology , Nanovirus/physiology , RNA Recognition Motif Proteins/metabolism , Viral Nonstructural Proteins/metabolism , Arabidopsis/virology , Cytoplasmic Granules/metabolism , Pisum sativum/virology , Plant Cells , Protein Binding , Protein Transport , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Stress, Physiological
17.
FEBS Open Bio ; 6(11): 1141-1154, 2016 11.
Article in English | MEDLINE | ID: mdl-27833854

ABSTRACT

Eukaryotic nuclei are subdivided into subnuclear structures. Among the most prominent of these structures are the nucleolus and the PML nuclear bodies (PML-NBs). PML-NBs are spherical multiprotein aggregates of varying size localized in the interchromosomal area. PML-NB formation is dependent on the presence of the promyelocytic leukemia protein (PML) as well as on post-translational modification of core components by covalent attachment of the small ubiquitin-like modifier (SUMO). So far, PML-NBs as well as PML have been described in mammalian cells only, whereas no orthologs are known in the plant kingdom. In order to investigate conserved mechanisms in PML targeting, we expressed human PML (hPML) fused to the GFP in Nicotiana benthamiana. Using confocal laser scanning microscopy and coimmunoprecipitation followed by mass spectrometric analysis, we found the fusion protein in association with nucleolar constituents. Importantly, mutants of hPML, which are no longer SUMOylated, showed altered localizations, implying SUMO-dependent targeting of hPML in plants as has previously been shown for mammalian cells. Interestingly, in the presence of proteasome inhibitors, hPML could also be found in the nucleolus of mammalian cells suggesting conserved targeting mechanisms of PML across kingdoms. Finally, Solanum tuberosum COP1, a proposed PML-like protein from plants, was fused to the red fluorescent protein (RFP) and coexpressed with hPML::eGFP. Microscopic analysis confirmed the localization of COP1::RFP in nuclear speckles. However, hPML::eGFP did not colocalize with COP1::RFP. Hence, we conclude that plants do not possess specialized PML-NBs, but that their functions may be covered by other subnuclear structures like the nucleolus. Database Proteomics data have been deposited to the ProteomeXchange Consortium with the identifier PXD004254.

18.
Viruses ; 8(8)2016 08 18.
Article in English | MEDLINE | ID: mdl-27548200

ABSTRACT

The human cytomegalovirus (HCMV)-encoded cyclin-dependent kinase (CDK) ortholog pUL97 associates with human cyclin B1 and other types of cyclins. Here, the question was addressed whether cyclin interaction of pUL97 and additional viral proteins is detectable by mass spectrometry-based approaches. Proteomic data were validated by coimmunoprecipitation (CoIP), Western blot, in vitro kinase and bioinformatic analyses. Our findings suggest that: (i) pUL97 shows differential affinities to human cyclins; (ii) pUL97 inhibitor maribavir (MBV) disrupts the interaction with cyclin B1, but not with other cyclin types; (iii) cyclin H is identified as a new high-affinity interactor of pUL97 in HCMV-infected cells; (iv) even more viral phosphoproteins, including all known substrates of pUL97, are detectable in the cyclin-associated complexes; and (v) a first functional validation of pUL97-cyclin B1 interaction, analyzed by in vitro kinase assay, points to a cyclin-mediated modulation of pUL97 substrate preference. In addition, our bioinformatic analyses suggest individual, cyclin-specific binding interfaces for pUL97-cyclin interaction, which could explain the different strengths of interactions and the selective inhibitory effect of MBV on pUL97-cyclin B1 interaction. Combined, the detection of cyclin-associated proteins in HCMV-infected cells suggests a complex pattern of substrate phosphorylation and a role of cyclins in the fine-modulation of pUL97 activities.


Subject(s)
Cyclin-Dependent Kinases/metabolism , Cyclins/metabolism , Cytomegalovirus/physiology , Host-Pathogen Interactions , Viral Proteins/metabolism , Blotting, Western , Cell Line , Computational Biology , Humans , Immunoprecipitation , Proteomics
19.
Proteomes ; 3(4): 411-423, 2015 Nov 12.
Article in English | MEDLINE | ID: mdl-28248277

ABSTRACT

Clavibacter michiganensis, subsp. michiganensis is a Gram-positive plant pathogen infecting tomato (Solanum lycopersicum). Despite a considerable economic importance due to significant losses of infected plants and fruits, knowledge about virulence factors of C. michiganensis subsp. michiganensis and host-pathogen interactions on a molecular level are rather limited. In the study presented here, the proteome of culture supernatants from C. michiganensis subsp. michiganensis NCPPB382 was analyzed. In total, 1872 proteins were identified in M9 and 1766 proteins in xylem mimicking medium. Filtration of supernatants before protein precipitation reduced these to 1276 proteins in M9 and 976 proteins in the xylem mimicking medium culture filtrate. The results obtained indicate that C. michiganensis subsp. michiganensis reacts to a sucrose- and glucose-depleted medium similar to the xylem sap by utilizing amino acids and host cell polymers as well as their degradation products, mainly peptides, amino acids and various C5 and C6 sugars. Interestingly, the bacterium expresses the previously described virulence factors Pat-1 and CelA not exclusively after host cell contact in planta but already in M9 minimal and xylem mimicking medium.

20.
Elife ; 32014 Jun 23.
Article in English | MEDLINE | ID: mdl-24957336

ABSTRACT

Peptidoglycans (PGNs) are immunogenic bacterial surface patterns that trigger immune activation in metazoans and plants. It is generally unknown how complex bacterial structures such as PGNs are perceived by plant pattern recognition receptors (PRRs) and whether host hydrolytic activities facilitate decomposition of bacterial matrices and generation of soluble PRR ligands. Here we show that Arabidopsis thaliana, upon bacterial infection or exposure to microbial patterns, produces a metazoan lysozyme-like hydrolase (lysozyme 1, LYS1). LYS1 activity releases soluble PGN fragments from insoluble bacterial cell walls and cleavage products are able to trigger responses typically associated with plant immunity. Importantly, LYS1 mutant genotypes exhibit super-susceptibility to bacterial infections similar to that observed on PGN receptor mutants. We propose that plants employ hydrolytic activities for the decomposition of complex bacterial structures, and that soluble pattern generation might aid PRR-mediated immune activation in cell layers adjacent to infection sites.


Subject(s)
Arabidopsis/immunology , Arabidopsis/microbiology , Bacteria/metabolism , Cell Wall/metabolism , Plant Immunity , Arabidopsis/genetics , Base Sequence , Gene Expression Regulation, Plant , Hydrolysis , Ligands , Molecular Sequence Data , Muramidase/chemistry , Peptides/chemistry , Peptidoglycan/chemistry , Plants, Genetically Modified/immunology , Plants, Genetically Modified/microbiology , Sequence Homology, Nucleic Acid , Nicotiana/genetics , Nicotiana/microbiology
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