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1.
Cancers (Basel) ; 15(23)2023 Dec 04.
Article in English | MEDLINE | ID: mdl-38067407

ABSTRACT

Secreted phosphoprotein-1 (SPP1) expression is differentially altered in many malignancies and could serve as a potential prognostic biomarker. Recent findings indicated that SPP1 possesses a broader role in bladder cancer (BC) pathogenesis than previously envisioned; however, the underlying mechanisms governing its expression, cellular localization, prognostic value and immune-related role in bladder cancer remain poorly understood. The expression and the prognosis value of SPP1 were assessed using immunohistochemistry (IHC) staining on a tissue microarray. SPP1 expression was correlated with the clinicopathological parameters, and survival analysis was calculated using a Kaplan-Meier plotter. Bioinformatics analysis of TCGA data was queried using UALCAN, CIBERSORT and TIMER datasets to decipher the biological processes enrichment pattern, protein-protein interactions and characterize tumor-infiltrating immune cells, respectively. IHC revealed that SPP1 expression is significantly associated with tumor type, stage, grade and smoking status. The Kaplan-Meier survival curve showed that low SPP1 expression is an unfavorable prognostic indicator in bladder cancer patients (p = 0.02, log-rank). The significant increased expression of the SPP1 level is associated with evident hypomethylation of the gene promoter in cancer compared to normal tissues in the TCGA-bladder dataset. Missense mutation is the most frequent genetic alteration of the SPP1 gene. Protein-protein interactions demonstrated that SPP1 shares the same network with many important genes and is involved in many signaling pathways and biological processes. TIMER reported a significant correlation between SPP1 expression and multiple immune cells infiltration. Furthermore, the expression of SPP1 was found to be positively correlated with a number of immune checkpoint genes such as PD-1 and CTLA4. The current investigation indicates that the SPP1 protein could serve as a prognostic biomarker and merit further investigation to validate its clinical usefulness in patients with bladder cancer.

2.
Microb Genom ; 9(9)2023 09.
Article in English | MEDLINE | ID: mdl-37656160

ABSTRACT

Respiratory syncytial virus (RSV), or human orthopneumovirus, is a major cause of acute lower respiratory infection (ALRI), particularly in young children, causing significant morbidity and mortality. We used pathogen genomics to characterize the population structure and genetic signatures of RSV isolates circulating in children in New South Wales between 2016 and 2018 and to understand the evolutionary dynamics of these strains in the context of publicly available RSV genomes from the region and globally. Whole-genome phylogenetic analysis demonstrated the co-circulation of a few major RSV clades in the paediatric population from Sydney. The whole-genome-based genotypes A23 (RSV-A ON1-like genotype) and B6 (RSV-B BA9-like genotype) were the predominant RSV-A and RSV-B genotypes circulating during the study period, respectively. These genotypes were characterized with high levels of diversity of predicted N- and O-linked glycosylation patterns in both the G and F glycoproteins. Interestingly, a novel 72-nucleotide triplication in the sequence that corresponds to the C-terminal region of the G gene was identified in four of the A23 genotype sequenced in this study. Consistently, the population dynamics analysis demonstrated a continuous increase in the effective population size of A23 and B6 genotypes globally. Further investigations including functional mapping of mutations and identifying the impact of sequence changes on virus fitness are highly required. This study highlights the potential impact of an integrated approach that uses WG-based phylogeny and studying selective pressure events in understanding the emergence and dissemination of RSV genotypes.


Subject(s)
Genomics , Respiratory Tract Infections , Child , Humans , Child, Preschool , Phylogeny , Respiratory Syncytial Viruses , Genotype , Australia
3.
J Clin Lab Anal ; 35(2): e23628, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33305405

ABSTRACT

Papillary thyroid carcinoma (PTC) is the most common endocrine malignancy among other endocrine tumors, and BRAFV600E is a frequent genetic mutation occurring in the disease. Although different molecular techniques, most importantly sequencing has been widely recognized as a gold standard but molecular diagnosis remains an expensive, laborious, and time-intensive process. Recently, immunohistochemistry (IHC) with anti-BRAF V600E (VE1) antibody has increased practical utility and implemented clinically for the detection of BRAFV600E mutation. Therefore, the study aimed to evaluate diagnostic accuracy of VE1 IHC for detecting the BRAFV600E mutation frequency and clinical implementation in diagnostic laboratories. In this study, 72 formalin fixed paraffin-embedded tissues (FFPE) were used to determine the BRAFV600E mutation status using IHC and Sanger sequencing. The mutation was found in 29% and 28% cases using IHC and Sanger sequencing, respectively. Furthermore, the results showed 100% sensitivity, 98.07% specificity, 95.2% positive predictive value, and 100% negative predictive value. Notably, significant associations were found between BRAFV600E status and tumor stage, tumor focality, and extrathyroidal extensions, respectively. VE1 IHC was found to be a highly sensitive, specific, and diagnostically accurate method in this cohort. Therefore, BRAFV600E detection through IHC has been considered as the best tailored technique for routine pathology laboratories.


Subject(s)
DNA Mutational Analysis/methods , Immunohistochemistry/methods , Proto-Oncogene Proteins B-raf/genetics , Thyroid Cancer, Papillary/genetics , Thyroid Neoplasms/genetics , Adult , Antibodies , Female , Humans , Male , Middle Aged , Proto-Oncogene Proteins B-raf/immunology , Retrospective Studies , Thyroid Cancer, Papillary/pathology , Thyroid Neoplasms/pathology
4.
Nat Commun ; 11(1): 2763, 2020 06 02.
Article in English | MEDLINE | ID: mdl-32488076

ABSTRACT

Malaria parasites complete their intra-erythrocytic developmental cycle (IDC) in multiples of 24 h suggesting a circadian basis, but the mechanism controlling this periodicity is unknown. Combining in vivo and in vitro approaches utilizing rodent and human malaria parasites, we reveal that: (i) 57% of Plasmodium chabaudi genes exhibit daily rhythms in transcription; (ii) 58% of these genes lose transcriptional rhythmicity when the IDC is out-of-synchrony with host rhythms; (iii) 6% of Plasmodium falciparum genes show 24 h rhythms in expression under free-running conditions; (iv) Serpentine receptor 10 (SR10) has a 24 h transcriptional rhythm and disrupting it in rodent malaria parasites shortens the IDC by 2-3 h; (v) Multiple processes including DNA replication, and the ubiquitin and proteasome pathways, are affected by loss of coordination with host rhythms and by disruption of SR10. Our results reveal malaria parasites are at least partly responsible for scheduling the IDC and coordinating their development with host daily rhythms.


Subject(s)
Circadian Rhythm/physiology , Erythropoiesis/physiology , Host-Parasite Interactions/physiology , Malaria/metabolism , Protozoan Proteins/metabolism , Receptors, G-Protein-Coupled/metabolism , Secologanin Tryptamine Alkaloids/metabolism , Animals , Caenorhabditis elegans Proteins , Disease Models, Animal , Female , Gene Expression , Host-Parasite Interactions/genetics , Humans , Malaria/parasitology , Mice , Mice, Knockout , Plasmodium chabaudi/genetics , Plasmodium chabaudi/growth & development , Plasmodium falciparum/genetics , Plasmodium falciparum/growth & development , Protozoan Proteins/genetics , Receptors, G-Protein-Coupled/genetics , Rodentia , Transcriptome
5.
J Clin Microbiol ; 54(8): 2014-22, 2016 08.
Article in English | MEDLINE | ID: mdl-27225410

ABSTRACT

Human infections with Salmonella enterica subspecies enterica serovar Senftenberg are often associated with exposure to poultry flocks, farm environments, or contaminated food. The recent emergence of multidrug-resistant isolates has raised public health concerns. In this study, comparative genomics and phenotypic analysis were used to characterize 14 Salmonella Senftenberg clinical isolates recovered from multiple outbreaks in Shenzhen and Shanghai, China, between 2002 and 2011. Single-nucleotide polymorphism analyses identified two phylogenetically distinct clades of S Senftenberg, designated SC1 and SC2, harboring variations in Salmonella pathogenicity island 1 (SPI-1) and SPI-2 and exhibiting distinct biochemical and phenotypic signatures. Although the two variants shared the same serotype, the SC2 isolates of sequence type 14 (ST14) harbored intact SPI-1 and -2 and hence were characterized by possessing efficient invasion capabilities. In contrast, the SC1 isolates had structural deletion patterns in both SPI-1 and -2 that correlated with an impaired capacity to invade cultured human cells and also the year of their isolation. These atypical SC1 isolates also lacked the capacity to produce hydrogen sulfide. These findings highlight the emergence of atypical Salmonella Senftenberg variants in China and provide genetic validation that variants lacking SPI-1 and regions of SPI-2, which leads to impaired invasion capacity, can still cause clinical disease. These data have identified an emerging public health concern and highlight the need to strengthen surveillance to detect the prevalence and transmission of nontyphoidal Salmonella species.


Subject(s)
Disease Outbreaks , Salmonella Infections/epidemiology , Salmonella Infections/microbiology , Salmonella enterica/classification , Salmonella enterica/isolation & purification , Serogroup , Adult , Aged , Bacterial Typing Techniques , China/epidemiology , Cluster Analysis , Female , Genotype , Humans , Male , Middle Aged , Phenotype , Phylogeny , Polymorphism, Single Nucleotide , Salmonella enterica/genetics , Young Adult
6.
Genome Res ; 24(10): 1676-85, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25015382

ABSTRACT

Global production of chickens has trebled in the past two decades and they are now the most important source of dietary animal protein worldwide. Chickens are subject to many infectious diseases that reduce their performance and productivity. Coccidiosis, caused by apicomplexan protozoa of the genus Eimeria, is one of the most important poultry diseases. Understanding the biology of Eimeria parasites underpins development of new drugs and vaccines needed to improve global food security. We have produced annotated genome sequences of all seven species of Eimeria that infect domestic chickens, which reveal the full extent of previously described repeat-rich and repeat-poor regions and show that these parasites possess the most repeat-rich proteomes ever described. Furthermore, while no other apicomplexan has been found to possess retrotransposons, Eimeria is home to a family of chromoviruses. Analysis of Eimeria genes involved in basic biology and host-parasite interaction highlights adaptations to a relatively simple developmental life cycle and a complex array of co-expressed surface proteins involved in host cell binding.


Subject(s)
Eimeria/genetics , Genome, Protozoan , Protozoan Proteins/genetics , Animals , Cell Line , Chickens , Chromosome Mapping , Coccidiosis/parasitology , Coccidiosis/veterinary , Eimeria/classification , Gene Expression Profiling , Phylogeny , Poultry Diseases/parasitology , Proteome , Synteny
7.
PLoS Pathog ; 9(5): e1003346, 2013 May.
Article in English | MEDLINE | ID: mdl-23675298

ABSTRACT

The apicomplexan parasite Theileria annulata transforms infected host cells, inducing uncontrolled proliferation and clonal expansion of the parasitized cell population. Shortly after sporozoite entry into the target cell, the surrounding host cell membrane is dissolved and an array of host cell microtubules (MTs) surrounds the parasite, which develops into the transforming schizont. The latter does not egress to invade and transform other cells. Instead, it remains tethered to host cell MTs and, during mitosis and cytokinesis, engages the cell's astral and central spindle MTs to secure its distribution between the two daughter cells. The molecular mechanism by which the schizont recruits and stabilizes host cell MTs is not known. MT minus ends are mostly anchored in the MT organizing center, while the plus ends explore the cellular space, switching constantly between phases of growth and shrinkage (called dynamic instability). Assuming the plus ends of growing MTs provide the first point of contact with the parasite, we focused on the complex protein machinery associated with these structures. We now report how the schizont recruits end-binding protein 1 (EB1), a central component of the MT plus end protein interaction network and key regulator of host cell MT dynamics. Using a range of in vitro experiments, we demonstrate that T. annulata p104, a polymorphic antigen expressed on the schizont surface, functions as a genuine EB1-binding protein and can recruit EB1 in the absence of any other parasite proteins. Binding strictly depends on a consensus SxIP motif located in a highly disordered C-terminal region of p104. We further show that parasite interaction with host cell EB1 is cell cycle regulated. This is the first description of a pathogen-encoded protein to interact with EB1 via a bona-fide SxIP motif. Our findings provide important new insight into the mode of interaction between Theileria and the host cell cytoskeleton.


Subject(s)
Antigens, Protozoan/metabolism , Host-Parasite Interactions/physiology , Microtubule-Associated Proteins/metabolism , Microtubules/parasitology , Theileria annulata/physiology , Amino Acid Sequence , Animals , Antigens, Protozoan/genetics , Blotting, Western , COS Cells , Cattle , Chlorocebus aethiops , Fluorescent Antibody Technique , Humans , Mice , Microtubules/metabolism , Molecular Sequence Data , Protein Transport/physiology , Schizonts/metabolism
8.
BMC Bioinformatics ; 11: 160, 2010 Mar 30.
Article in English | MEDLINE | ID: mdl-20353553

ABSTRACT

BACKGROUND: Small molecular cofactors or ligands play a crucial role in the proper functioning of cells. Accurate annotation of their target proteins and binding sites is required for the complete understanding of reaction mechanisms. Nicotinamide adenine dinucleotide (NAD+ or NAD) is one of the most commonly used organic cofactors in living cells, which plays a critical role in cellular metabolism, storage and regulatory processes. In the past, several NAD binding proteins (NADBP) have been reported in the literature, which are responsible for a wide-range of activities in the cell. Attempts have been made to derive a rule for the binding of NAD+ to its target proteins. However, so far an efficient model could not be derived due to the time consuming process of structure determination, and limitations of similarity based approaches. Thus a sequence and non-similarity based method is needed to characterize the NAD binding sites to help in the annotation. In this study attempts have been made to predict NAD binding proteins and their interacting residues (NIRs) from amino acid sequence using bioinformatics tools. RESULTS: We extracted 1556 proteins chains from 555 NAD binding proteins whose structure is available in Protein Data Bank. Then we removed all redundant protein chains and finally obtained 195 non-redundant NAD binding protein chains, where no two chains have more than 40% sequence identity. In this study all models were developed and evaluated using five-fold cross validation technique on the above dataset of 195 NAD binding proteins. While certain type of residues are preferred (e.g. Gly, Tyr, Thr, His) in NAD interaction, residues like Ala, Glu, Leu, Lys are not preferred. A support vector machine (SVM) based method has been developed using various window lengths of amino acid sequence for predicting NAD interacting residues and obtained maximum Matthew's correlation coefficient (MCC) 0.47 with accuracy 74.13% at window length 17. We also developed a SVM based method using evolutionary information in the form of position specific scoring matrix (PSSM) and obtained maximum MCC 0.75 with accuracy 87.25%. CONCLUSION: For the first time a sequence-based method has been developed for the prediction of NAD binding proteins and their interacting residues, in the absence of any prior structural information. The present model will aid in the understanding of NAD+ dependent mechanisms of action in the cell. To provide service to the scientific community, we have developed a user-friendly web server, which is available from URL http://www.imtech.res.in/raghava/nadbinder/.


Subject(s)
NAD/chemistry , Proteins/chemistry , Amino Acid Sequence , Binding Sites , Databases, Protein , Pattern Recognition, Automated/methods , Proteins/metabolism , Sequence Alignment , Sequence Analysis, Protein
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