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AIDS Research and Therapy Nov 2023Human immunodeficiency virus (HIV) infection is associated with an elevated incidence of cervical cancer, and accelerated disease progression, but the underlying...
BACKGROUND
Human immunodeficiency virus (HIV) infection is associated with an elevated incidence of cervical cancer, and accelerated disease progression, but the underlying mechanisms are not well understood. This study aimed to investigate the relationship between HIV infection and epithelial-mesenchymal transition (EMT) in cervical cancer.
METHODS
Tissue samples from HIV-positive and negative patients with cervical intraepithelial neoplasia (CIN) and cervical cancer were analyzed for EMT-related proteins. Human cervical cancer SiHa cells were treated with HIV Tat and gp120 proteins to test their effects on EMT, migration, and invasion.
RESULTS
HIV-positive patients had lower E-cadherin and cytokeratin, and higher N-cadherin and vimentin levels than HIV-negative patients. HIV Tat and gp120 proteins induced EMT, migration, and invasion in SiHa cells. Transcriptome sequencing analysis revealed that, compared to the control group, the protein-treated group showed upregulation of 22 genes and downregulation of 77 genes. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses revealed the involvement of the Wnt signaling pathway in EMT. Further analysis of gene expression related to this pathway revealed upregulation of DVL1, TCF7, KRT17, and VMAC, while GSK3β, SFRP2, and CDH1 were downregulated. Immunofluorescence assay demonstrated that HIVgp120 and Tat proteins treatment induced elevated β-catenin expression with nuclear accumulation in SiHa cells.
CONCLUSIONS
The treatment of SiHa cells with HIV Tat and gp120 proteins induces EMT and activates the Wnt/β-catenin pathway, suggesting that the Wnt/β-catenin pathway may play a crucial role in promoting EMT progression in cervical lesion tissues of HIV-infected patients.
Topics: Female; Humans; beta Catenin; Uterine Cervical Neoplasms; Cell Line, Tumor; Gene Products, tat; Epithelial-Mesenchymal Transition; HIV Infections
PubMed: 37981694
DOI: 10.1186/s12981-023-00577-1 -
ELife Jan 2016A virus protein called Tat plays a dual role in HIV infection by regulating the expression of genes belonging to the virus and genes belonging to the host cells.
A virus protein called Tat plays a dual role in HIV infection by regulating the expression of genes belonging to the virus and genes belonging to the host cells.
Topics: HIV; HIV Infections; Host-Pathogen Interactions; Humans; Transcription, Genetic; Virus Replication; tat Gene Products, Human Immunodeficiency Virus
PubMed: 26783762
DOI: 10.7554/eLife.12686 -
Saudi Journal of Biological Sciences Mar 2019We have aimed to investigate the expression of genes related to rosmarinic acid (RA) synthesis and rosmarinic acid content in 2 cultivars, green (cinnamon) and purple...
We have aimed to investigate the expression of genes related to rosmarinic acid (RA) synthesis and rosmarinic acid content in 2 cultivars, green (cinnamon) and purple (red rubin) basil. Specifically, genes related to rosmarinic acid biosynthesis were cloned and characterized for . . We obtained partial cDNAs of tyrosine aminotransferase (TAT) and 4-hydroxyphenylpyruvate reductase (HPPR), which were of 323 bp and 616 bp in size, respectively. The transcription levels of most genes related to rosmarinic acid synthesis were higher in green basil compared to purple basil, except for and in the root. The highest expression was obtained in the leaves of green basil for all genes and the roots of purple basil for all genes, except for TAT. The highest rosmarinic acid content was obtained in the leaves of both cultivars, with higher RA accumulating in green basil compared to purple basil. The leaves had the highest RA content out of all plant organs, with the RA accumulation in the leaves of green basil being 1.64 times higher compared to purple basil. Further study is required to investigate whether a similar trend is observed across . cultivars of different color types.
PubMed: 30899160
DOI: 10.1016/j.sjbs.2017.03.010 -
Translational Oncology Jan 2022Clinic therapy of acute myeloid leukemia (AML) remains unsatisfactory that urges for development of novel strategies. Recent studies identified ANP32A as a novel...
Clinic therapy of acute myeloid leukemia (AML) remains unsatisfactory that urges for development of novel strategies. Recent studies identified ANP32A as a novel biomarker of unfavorable outcome of leukemia, which promoted leukemogenesis by increasing H3 acetylation and the expression of lipid metabolism genes. It is of great significance to investigate whether targeting ANP32A is a novel strategy for leukemia therapy. To target ANP32A, we identified a peptide that competed with ANP32A to bind to histone 3 (termed as H3-binding peptide, H3BP). Disrupting ANP32A and H3 interaction by the overexpression of H3BP-GFP fusion protein mimicked the effect of ANP32A knockdown, impaired H3 acetylation on multiple locus of target genes, reduced proliferation, and caused apoptosis in leukemia cells. Furthermore, a synthesized membrane-penetrating peptide TAT-H3BP effectively entered into leukemia cells and phenocopied such effect. In vivo, TAT-H3BP showed potent efficacy against leukemia: Intra-tumor injection of TAT-H3BP significantly reduced the volume of subcutaneous tumors in nude mice and recipient mice engrafted with TAT-H3BP-pretreated 6133/MPL W515L cells exhibited ameliorated leukemia burden and prolonged survival. Noticeably, TAT-H3BP efficiently suppressed proliferation and colony-forming unit of human primary AML cells without affecting normal cord blood cells. Our findings demonstrate that intervening the physical interaction of ANP32A with H3 impairs the oncogenicity of ANP32A and may be a promising therapeutic strategy against AML.
PubMed: 34678588
DOI: 10.1016/j.tranon.2021.101245 -
Virus Research May 2018For the production of viral genomic RNA, HIV-1 is dependent on an early viral protein, Tat, which is required for high-level transcription. The quantity of viral RNA...
For the production of viral genomic RNA, HIV-1 is dependent on an early viral protein, Tat, which is required for high-level transcription. The quantity of viral RNA detectable in blood of HIV-1 infected individuals varies dramatically, and a factor involved could be the efficiency of Tat protein variants to stimulate RNA transcription. HIV-1 virulence, measured by set-point viral load, has been observed to increase over time in the Netherlands and elsewhere. Investigation of tat gene evolution in clinical isolates could discover a role of Tat in this changing virulence. A dataset of 291 Dutch HIV-1 subtype B tat genes, derived from full-length HIV-1 genome sequences from samples obtained between 1985-2012, was used to analyse the evolution of Tat. Twenty-two patient-derived tat genes, and the control Tat were analysed for their capacity to stimulate expression of an LTR-luciferase reporter gene construct in diverse cell lines, as well as for their ability to complement a tat-defective HIV-1 clone. Analysis of 291 historical tat sequences from the Netherlands showed ample amino acid (aa) variation between isolates, although no specific mutations were selected for over time. Of note, however, the encoded protein varied its length over the years through the loss or gain of stop codons in the second exon. In transmission clusters, a selection against the shorter Tat86 ORF was apparent in favour of the more common Tat101 version, likely due to negative selection against Tat86 itself, although random drift, transmission bottlenecks, or linkage to other variants could also explain the observation. There was no correlation between Tat length and set-point viral load; however, the number of non-intermediate variants in our study was small. In addition, variation in the length of Tat did not significantly change its capacity to stimulate transcription. From 1985 till 2012, variation in the length of the HIV-1 subtype B tat gene is increasingly found in the Dutch epidemic. However, as Tat proteins did not differ significantly in their capacity to stimulate transcription elongation in vitro, the increased HIV-1 virulence seen in recent years could not be linked to an evolving viral Tat protein.
Topics: Codon; Evolution, Molecular; Gene Expression Regulation, Viral; Genome, Viral; HIV Infections; HIV Long Terminal Repeat; HIV-1; Humans; Luciferases; Netherlands; Open Reading Frames; RNA, Viral; Transcription, Genetic; Transcriptional Activation; Viral Load; tat Gene Products, Human Immunodeficiency Virus
PubMed: 29654800
DOI: 10.1016/j.virusres.2018.04.008 -
Frontiers in Plant Science 2018MAFF303099 is a rhizobial strain that nodulates spp. A MAFF303099 mutant strain affected in the gene was generated. This strain presented an altered protein...
MAFF303099 is a rhizobial strain that nodulates spp. A MAFF303099 mutant strain affected in the gene was generated. This strain presented an altered protein secretion level to the culture supernatant and also a higher sensitivity to SDS. Its nodulation phenotype on showed the induction of small and colorless nodules, and in a larger number than those induced by the wild-type strain. In addition, these nodules presented defects in the degree of occupation by rhizobia. Two Rieske Fe/S proteins, encoded by the and genes, were predicted as potential Tat substrates in MAFF303099. The transcriptional expression of and genes was analyzed under different oxygen growth conditions. The gene was expressed constitutively, while the expression of the gene was only detected under anaerobic and microaerophilic conditions. Both genes were down-regulated in the mutant strain. and mRNAs from the wild-type strain were detected in nodules. Using a translational reporter peptide fusion, we found that the Mll2707 protein was only detectable in the wild-type strain. On the other hand, although Mlr0970 protein was detected in wild-type and mutant strains, its association with the membrane was favored in the wild-type strain. The and the mutant strains were affected in the cytochrome c oxidase activity. These results confirm that Mll2707 is required for cytochrome c-dependent respiration and that Tat functionality is required for the correct activity of Mll2707. The mutant strain showed a nodulation phenotype similar to the mutant strain, although it presented only a slight difference in comparison with wild-type strain in terms of nodule occupation. No defective phenotype was observed in the nodulation with the mutant strain. These results indicate that, of the two Rieske Fe/S proteins coded by MAFF303099, only Mll2707 expression is required for the induction of effective nodules, and that the functionality of the Tat system is necessary not only for the correct function of this protein, but also for some other protein required in an earlier stage of the nodulation process.
PubMed: 30515183
DOI: 10.3389/fpls.2018.01686 -
Archives of Medical Science : AMS Sep 2012Carbonic anhydrase III (CAIII) is remarkably abundant in slow skeletal muscles. It has multiple biological activities which could dissipate or resist some...
INTRODUCTION
Carbonic anhydrase III (CAIII) is remarkably abundant in slow skeletal muscles. It has multiple biological activities which could dissipate or resist some fatigue-related substances. In this study, we purified trans-activating transcriptional activator (TAT) fused CAIII protein and investigated its effect on C2C12 cell apoptosis induced by hypoxia/reoxygenation.
MATERIAL AND METHODS
The CAIII and TAT-CAIII genes were constructed, cloned into plasmid pET28a and expressed in Escherichia coli BL21 (DE3). The fusion proteins were purified with a nickel-nitrilotriacetic acid affinity chromatography column and then verified by Western blot and phosphatase activity staining subsequently. The C2C12 cells were treated respectively with serum-free medium containing 1 μM TAT-CAIII or 1 μM CAIII for 1 h and the intracellular distributions of fusion proteins were observed by indirect immunofluorescence. The effect of TAT-CAIII on C2C12 cell apoptosis induced by hypoxia/reoxygenation was detected by flow cytometry.
RESULTS
The CAIII and TAT-CAIII fusion proteins were expressed and purified successfully. After being cultured for 1 h, green fluorescence was visible in TAT-CAIII group cells under the fluorescence microscope, while no fluorescence was found in the CAIII group. Compared with the oxygen-glucose deprivation group, the apoptosis rate of C2C12 cells induced by hypoxia/reoxygenation in the TAT-CAIII group decreased significantly (p < 0.001).
CONCLUSIONS
The purified TAT-CAIII could be transferred into cells efficiently and clearly decreased the apoptosis rate of C2C12 cells induced by hypoxia/reoxygenation, which indicated that it had antioxidative activity. This study lays an experimental basis for future research on the relationship between CAIII and muscle fatigue.
PubMed: 23056085
DOI: 10.5114/aoms.2012.30295 -
Oncology Reports Mar 2019Hepatocellular carcinoma (HCC) is a lethal malignancy with high morbidity and mortality rates worldwide. The identification of prognosis‑associated biomarkers is...
Hepatocellular carcinoma (HCC) is a lethal malignancy with high morbidity and mortality rates worldwide. The identification of prognosis‑associated biomarkers is crucial to improve HCC patient survival. The present study aimed to explore potential predictive biomarkers for HCC. Differentially expressed genes (DEGs) were analyzed in the GSE36376 dataset using GEO2R. Hub genes were identified and further investigated for prognostic value in HCC patients. A risk score model and nomogram were constructed to predict HCC prognosis using the prognosis‑associated genes and clinical factors. Pearson's correlation was employed to show interactions among hub genes. Gene enrichment analysis was performed to identify detailed biological processes and pathways. A total of 71 DEGs were obtained and seven (ADH4, CYP2C8, CYP2C9, CYP8B1, SLC22A1, TAT and HSD17B13, all adjusted P≤0.05) of the 10 hub genes were identified as prognosis‑related genes for survival analysis in HCC patients, including alcohol dehydrogenase 4 (class II), pi polypeptide (ADH4), cytochrome p450 family 2 subfamily C member 8 (CYP2C8), cytochrome P450 family 2 subfamily C member 9 (CYP2C9), cytochrome P450 family 8 subfamily B member 1 (CYP8B1), solute carrier family 22 member 1 (SLC22A1), tyrosine aminotransferase (TAT) and hydroxysteroid 17‑β dehydrogenase 13 (HSD17B13). The risk score model could predict HCC prognosis and the nomogram visualized gene expression and clinical factors of probability for HCC prognosis. The majority of genes showed significant Pearson's correlations with others (41 Pearson correlations P≤0.01, four Pearson correlations P>0.05). GO analysis revealed that terms such as 'chemical carcinogenesis' and 'drug metabolism‑cytochrome P450' were enriched and may prove helpful to elucidate the mechanisms of hepatocarcinogenesis. Hub genes ADH4, CYP2C8, CYP2C9, CYP8B1, SLC22A1, TAT and HSD17B13 may be useful as predictive biomarkers for HCC prognosis.
Topics: Biomarkers, Tumor; Carcinoma, Hepatocellular; Computational Biology; Datasets as Topic; Gene Expression Profiling; Gene Expression Regulation, Neoplastic; Gene Regulatory Networks; Hepatectomy; Humans; Liver Neoplasms; Nomograms; Survival Analysis; Treatment Outcome
PubMed: 30628708
DOI: 10.3892/or.2019.6953 -
MBio Jun 2021The cell envelope of Gram-negative bacteria consists of two membranes surrounding the periplasm and peptidoglycan layer. β-Lactam antibiotics target the periplasmic...
The cell envelope of Gram-negative bacteria consists of two membranes surrounding the periplasm and peptidoglycan layer. β-Lactam antibiotics target the periplasmic penicillin-binding proteins that synthesize peptidoglycan, resulting in cell death. The primary means by which bacterial species resist the effects of β-lactam drugs is to populate the periplasmic space with β-lactamases. Resistance to β-lactam drugs is spread by lateral transfer of genes encoding β-lactamases from one species of bacteria to another. However, the resistance phenotype depends in turn on these "alien" protein sequences being recognized and exported across the cytoplasmic membrane by either the Sec or Tat protein translocation machinery of the new bacterial host. Here, we examine BKC-1, a carbapenemase from an unknown bacterial source that has been identified in a single clinical isolate of Klebsiella pneumoniae. BKC-1 was shown to be located in the periplasm, and functional in both K. pneumoniae and Escherichia coli. Sequence analysis revealed the presence of an unusual signal peptide with a twin arginine motif and a duplicated hydrophobic region. Biochemical assays showed this signal peptide directs BKC-1 for translocation by both Sec and Tat translocons. This is one of the few descriptions of a periplasmic protein that is functionally translocated by both export pathways in the same organism, and we suggest it represents a snapshot of evolution for a β-lactamase adapting to functionality in a new host. Bacteria can readily acquire plasmids via lateral gene transfer (LGT). These plasmids can carry genes for virulence and antimicrobial resistance (AMR). Of growing concern are LGT events that spread β-lactamases, particularly carbapenemases, and it is important to understand what limits this spread. This study provides insight into the sequence features of BKC-1 that exemplify the limitations on the successful biogenesis of β-lactamases, which is one factor limiting the spread of AMR phenotypes by LGT. With a very simple evolutionary adaptation, BKC-1 could become a more effective carbapenemase, underscoring the need to understand the evolution, adaptability, and functional assessment of newly reported β-lactamases rapidly and thoroughly.
Topics: Anti-Bacterial Agents; Bacterial Proteins; Biological Transport; Escherichia coli; Gene Products, tat; Humans; Klebsiella Infections; Klebsiella pneumoniae; Microbial Sensitivity Tests; Periplasm; SEC Translocation Channels; beta-Lactamases; beta-Lactams
PubMed: 34154411
DOI: 10.1128/mBio.01302-21 -
ASN Neuro Oct 2016White matter injury has been frequently reported in HIV patients. Previous studies showed that HIV-1 Tat (transactivator of transcription), a viral protein that is...
White matter injury has been frequently reported in HIV patients. Previous studies showed that HIV-1 Tat (transactivator of transcription), a viral protein that is produced and secreted by HIV-infected cells, is toxic to young, immature oligodendrocytes (OLGs). Adding Tat to the culture medium reduced the viability of immature OLGs, and the surviving OLGs exhibited reduced process networks. OLGs produce and secrete autotaxin (ATX), an ecto-enzyme containing a lysophospholipase D (lysoPLD) activity that converts lysophosphatidylcholine (LPC) to lysophosphatidic acid (LPA), a lipid signaling molecule that stimulates OLG differentiation. We hypothesized that Tat affects OLG development by interfering with the ATX-LPA signaling pathway. Our data show that Tat treatment leads to changes in the expression of OLG differentiation genes and the area of OLG process networks, both of which can be rescued by LPA. Tat-treated OLGs showed no change in LPA receptor expression but significantly decreased extracellular ATX levels and lysoPLD activity. In Tat transgenic mice, expression of Tat in vivo leads to decreased OLG ATX secretion. Furthermore, co-immunoprecipitation experiments revealed a potential physical interaction between Tat and ATX. Together, these data strongly suggest two functional implications of Tat blocking ATX's lysoPLD activity. On one hand, it attenuates OLG differentiation, and on the other hand it interferes with the protective effects of LPA on OLG process morphology.
PubMed: 27659560
DOI: 10.1177/1759091416669618