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Journal of Microbiology (Seoul, Korea) Aug 2022Decapping of mRNA is a key regulatory step for mRNA decay and translation. The RNA helicase, Dhh1, is known as a decapping activator and translation repressor in yeast...
Decapping of mRNA is a key regulatory step for mRNA decay and translation. The RNA helicase, Dhh1, is known as a decapping activator and translation repressor in yeast Saccharomyces cerevisiae. Dhh1 also functions as a gene-specific positive regulator in the expression of Ste12, a mating-specific transcription factor. A previous study showed that the N-erminal phosphorylation of Dhh1 regulates its association with the mRNA-binding protein, Puf6, to affect the protein translation of Ste12. Here, we investigated the roles of the phosphorylated residues of Dhh1 in yeast mating process and Ste12 expression. The phospho-deficient mutation, DHH1-T10A, was associated with decreased diploid formation during mating and decreased level of the Ste12 protein in response to α-mating pheromone. A kinase overexpression analysis revealed that Ste12 protein expression was affected by overexpression of Fus3 MAP kinase or Tpk2 kinase. Tpk2 was shown to be responsible for phosphorylation of Dhh1 at Thr10. Our study shows that overexpression of Fus3 or Tpk2 alters the Dhh1-Puf6 protein interaction and thereby affects Ste12 protein expression.
Topics: Cyclic AMP-Dependent Protein Kinases; DEAD-box RNA Helicases; Fungal Proteins; Gene Expression Regulation, Fungal; Mating Factor; Mitogen-Activated Protein Kinases; Phosphorylation; Protein Kinases; RNA, Messenger; RNA-Binding Proteins; Saccharomyces cerevisiae; Saccharomyces cerevisiae Proteins; Transcription Factors
PubMed: 35835957
DOI: 10.1007/s12275-022-2213-x -
Immunity, Inflammation and Disease Dec 2021The chromosomal region 17q21 harbors the human orosomucoid-like 3 (ORMDL3) gene and has been linked to asthma and other inflammatory diseases. ORMDL3 is involved in the...
INTRODUCTION
The chromosomal region 17q21 harbors the human orosomucoid-like 3 (ORMDL3) gene and has been linked to asthma and other inflammatory diseases. ORMDL3 is involved in the unfolded protein response (UPR), lipid metabolism, and inflammatory reactions. We investigated the effects of ORMDL3 overexpression in RBL-2H3 cells to determine the contribution of ORMDL3 to inflammatory disease development.
METHODS
We generated ORMDL3 stably overexpressing RBL-2H3 cells to assess degranulation, transcriptional upregulation of interleukin-4 (IL-4), tumor necrosis factor-α (TNF-α), monocyte chemoattractant protein-1 (MCP-1), and mitogen-activated protein kinase (MAPK) phosphorylation via FcεRI. In addition, we examined the effects of ORMDL3 overexpression on thapsigargin (TG)-mediated proinflammatory cytokine transcription and UPR by monitoring MAPK, protein kinase-like endoplasmic reticulum kinase (PERK), and inositol-requiring enzyme 1 (IRE1) phosphorylation.
RESULTS
Overexpression of ORMDL3 enhanced IL-4, TNF-α, and MCP-1 expression after FcεRI cross-linking, whereas the sphingosine-1-phosphate (S1P) agonist FTY720 suppressed this enhancement. There was no significant difference in degranulation and MAPK phosphorylation via FcεRI-mediated activation between vector-transfected and ORMDL3-overexpressing cells. ORMDL3 overexpression accelerated TG-mediated PERK phosphorylation, while MAPK phosphorylation and proinflammatory cytokine expression showed no significant changes in ORMDL3-overexpressing cells.
CONCLUSIONS
Our findings suggest that ORMDL3 plays an important role in regulating proinflammatory cytokine expression via the S1P pathway and selectively affects the UPR pathway in mast cells.
Topics: Cell Degranulation; Cytokines; Endoplasmic Reticulum; Humans; Membrane Proteins; Orosomucoid; Phosphorylation; Receptors, IgE; Thapsigargin
PubMed: 34288557
DOI: 10.1002/iid3.489 -
International Journal of Molecular... Aug 2020Post-implantation cell survival and angio-/vasculogenesis are critical for the success of cell-based regenerative strategies. The current study aimed to overexpress...
Post-implantation cell survival and angio-/vasculogenesis are critical for the success of cell-based regenerative strategies. The current study aimed to overexpress B-cell lymphoma 2 () gene in dental pulp stem cells (DPSCs) and examine the anti-apoptotic and angio-/vasculogenic effects both in-vitro and in-vivo. DPSCs were transduced with Bcl-2-green fluorescent protein (GFP) lentiviral particles and examined for cell proliferation and apoptosis. The cells were cultured under normoxic or hypoxic (0.5 mM CoCl) conditions and examined for the expression of angiogenic factors and effects on endothelial cell proliferation, migration and vessel morphogenesis. Cells with or without hypoxic preconditioning were used in in-vivo Matrigel plug assay to study the post-implantation cell survival and angio-/vasculogenesis. Bcl-2-overexpressing-DPSCs showed significantly lower apoptosis than that of null-GFP-DPSCs under serum-free conditions. Under hypoxia, Bcl-2-overexpressing-DPSCs expressed significantly higher levels of vascular endothelial growth factor compared to that under normoxia and null-GFP-DPSCs. Consequently, Bcl-2-overexpressing-DPSCs significantly enhanced endothelial cell proliferation, migration and vascular tube formation on Matrigel. Immunohistological assessment of in-vivo transplanted Matrigel plugs showed significantly higher cell survival and vasculature in hypoxic preconditioned Bcl-2-overexpressing-DPSC group compared to null-GFP-DPSC group. In conclusion, Bcl-2 overexpression and hypoxic-preconditioning could be synergistically used to enhance post-implantation cell survival and angio-/vasculogenic properties of DPSCs.
Topics: Animals; Cell Differentiation; Cell Hypoxia; Cell Proliferation; Cell Survival; Cells, Cultured; Dental Pulp; Human Umbilical Vein Endothelial Cells; Humans; Hypoxia-Inducible Factor 1, alpha Subunit; Lentivirus; Mice; Proto-Oncogene Proteins c-bcl-2; Stem Cell Transplantation; Stem Cells; Transduction, Genetic; Vascular Endothelial Growth Factor A
PubMed: 32859045
DOI: 10.3390/ijms21176159 -
Open Life Sciences 2021Vascular hyporesponsiveness in the shock decompensation period is an important factor leading to death. Myosin light chain 20 (MLC) is the main effector protein that...
Vascular hyporesponsiveness in the shock decompensation period is an important factor leading to death. Myosin light chain 20 (MLC) is the main effector protein that regulates vascular reactivity. However, whether the change in semicarbazide-sensitive amine oxidase (SSAO) expression during hypoxia can change the MLC phosphorylation level, and its underlying mechanism were not clear. The amine oxidase copper containing 3 (AOC3) overexpressing adenovirus vector was constructed and transfected into rat intestinal microvascular endothelial cells (RIMECs) to overexpress SSAO, and the RIMECs were co-cultured with rat intestinal microvascular smooth muscle cells (RIMSCs). The changes in SSAO/inducible nitric oxide synthase (iNOS)/Rho associate coiled-coil containing protein kinase 1 (ROCK1) expression levels and MLC phosphorylation level were detected. Here we found that the increased SSAO by AOC3 overexpression can decrease the iNOS expression level and its activity after hypoxia. In addition, RIMSCs co-cultured with RIMECs overexpressed with AOC3 gene had significantly higher ROCK1 protein level and MLC phosphorylation level than RIMSCs co-cultured with normal RIMECs. Our study demonstrated that SSAO overexpression can significantly inhibit iNOS activity, promote RhoA/ROCK pathway activation, and increase the phosphorylation level of MLC, which might be the potential mechanism in relieving the vascular hyporesponsiveness during shock decompensation.
PubMed: 34722886
DOI: 10.1515/biol-2021-0114 -
Oxidative Medicine and Cellular... 2022Tumor necrosis factor--induced protein 8-like 2 (TIPE2), a novel immunoregulatory protein, has been reported to regulate inflammation and apoptosis. The role of TIPE2 in...
BACKGROUND
Tumor necrosis factor--induced protein 8-like 2 (TIPE2), a novel immunoregulatory protein, has been reported to regulate inflammation and apoptosis. The role of TIPE2 in cardiovascular disease, especially cardiac hypertrophy, has not been elucidated. Thus, the aim of the present study was to explore the role of TIPE2 in cardiac hypertrophy.
METHODS
Mice were subjected to aortic banding (AB) to induce an adverse hypertrophic model. To overexpress TIPE2, mice were injected with a lentiviral vector expressing TIPE2. Echocardiographic and hemodynamic analyses were used to evaluate cardiac function. Neonatal rat cardiomyocytes (NRCMs) and mouse peritoneal macrophages (MPMs) were isolated and stimulated with angiotensin II. NRCMs and MPM were also cocultured and stimulated with angiotensin II. Cells were transfected with Lenti-TIPE2 to overexpress TIPE2.
RESULTS
TIPE2 expression levels were downregulated in hypertrophic mouse hearts and in macrophages in heart tissue. TIPE2 overexpression attenuated pressure overload-induced cardiac hypertrophy, fibrosis, and cardiac dysfunction. Moreover, we found that TIPE2 overexpression in neonatal cardiomyocytes did not relieve the angiotensin II-induced hypertrophic response in vitro. Furthermore, TIPE2 overexpression downregulated TLR4 and NF-B signaling in macrophages but not in cardiomyocytes, which led to diminished inflammation in macrophages and consequently reduced the activation of hypertrophic Akt signaling in cardiomyocytes. TLR4 inhibition by TAK-242 did not enhance the antihypertrophic effect of TIPE2 overexpression.
CONCLUSIONS
The present study indicated that TIPE2 represses macrophage activation by targeting TLR4, subsequently inhibiting cardiac hypertrophy.
Topics: Angiotensin II; Animals; Cardiomegaly; Disease Models, Animal; Inflammation; Intracellular Signaling Peptides and Proteins; Macrophages; Mice; Mice, Inbred C57BL; Myocytes, Cardiac; Rats; Toll-Like Receptor 4; Tumor Necrosis Factor-alpha
PubMed: 35528518
DOI: 10.1155/2022/9469143 -
Current Genetics Apr 2021Under thermal stress, different protein quality control (PQC) strategies are activated to maintain an intact proteome, which may vary from one model system to another.... (Review)
Review
Under thermal stress, different protein quality control (PQC) strategies are activated to maintain an intact proteome, which may vary from one model system to another. Hence thermo-sensitive proteins that lose their active conformation might be refolded with the aid of chaperones or removed by the ubiquitin-proteasome system or the process of autophagy. We have recently developed thermo-sensitive reporters to study PQC in fission yeast and shown the relevance of a third adaptation strategy: the sequestration of misfolded proteins into inclusions which will prevent a rapid degradation and allow the refolding once stress ends. These protein inclusions, protein aggregate centers (PACs), contain a broad spectrum of misfolding/aggregation-prone proteins and chaperones involved in their assembly or dissolution. The chaperone couple Mas5/Ssa2 plays a crucial role in PAC formation, whereas the Hsp104 chaperone promotes their disassembly. The absence of aggregates observed in cells lacking Mas5 could be also explained by the activation of the transcription factor Hsf1 and the induction of chaperone genes, we have excluded this possibility here demonstrating that increased Hsf1 activity and the subsequent overexpression of chaperones do not prevent the assembly of protein aggregates. Protein deposition at certain locations also constitutes a tactic to inactivate proteins temporally. This is the case of Pyp1, the main phosphatase of the stress response kinase Sty1. Upon stress imposition, misfolded Pyp1 is sequestered into cytosolic protein foci while active Sty1 at the nucleus switches on the transcriptional response. In conclusion, we propose that the assembly of aggregation-like foci, PACs in fission yeast, is a crucial PQC strategy during heat stress, and that the Hsp40 chaperone Mas5 is required for PAC assembly and connects physiological and heat-shock triggered PQC.
Topics: HSP40 Heat-Shock Proteins; HSP70 Heat-Shock Proteins; Heat-Shock Proteins; Heat-Shock Response; Molecular Chaperones; Phosphoric Monoester Hydrolases; Protein Folding; Protein Serine-Threonine Kinases; Protein-Tyrosine Kinases; Saccharomyces cerevisiae; Saccharomyces cerevisiae Proteins
PubMed: 33386485
DOI: 10.1007/s00294-020-01135-2 -
PloS One 2019The Acinetobacter baumannii BlsA photoreceptor has an N-terminal (NT) BLUF domain and a C-terminal (CT) amino acid sequence with no significant homology to characterized...
The Acinetobacter baumannii BlsA photoreceptor has an N-terminal (NT) BLUF domain and a C-terminal (CT) amino acid sequence with no significant homology to characterized bacterial proteins. In this study, we tested the biological role of specific residues located in these BlsA regions. Site-directed mutagenesis, surface motility assays at 24°C and protein overexpression showed that residues Y7, Q51 and W92 are essential for not only light-regulated motility, but also BlsA's solubility when overexpressed in a heterologous host. In contrast, residues A29 and F32, the latter representing a difference when compared with other BLUF-containing photoreceptors, do not play a major role in BlsA's biological functions. Analysis of the CT region showed that the deletion of the last five BlsA residues has no significant effect on the protein's light-sensing and motility regulatory functions, but the deletion of the last 14 residues as well as K144E and K145E substitutions significantly alter light-regulated motility responses. In contrast to the NT mutants, these CT derivatives were overexpressed and purified to homogeneity to demonstrate that although these mutations do not significantly affect flavin binding and photocycling, they do affect BlsA's photodynamic properties. Notably, these mutations map within a potential fifth α-helical component that could play a role in predicted interactions between regulatory partners and BlsA, which could function as a monomer according to gel filtration data. All these observations indicate that although BlsA shares common structural and functional properties with unrelated photoreceptors, it also exhibits unique features that make it a distinct BLUF photoreceptor.
Topics: Acinetobacter baumannii; Bacterial Proteins; Mutation; Protein Domains
PubMed: 31415622
DOI: 10.1371/journal.pone.0220918 -
Molecular Carcinogenesis Mar 2022The FoxQ1 is an oncogenic transcription factor that is overexpressed in basal-like and luminal-type human breast cancers when compared to the normal mammary tissue. The...
The FoxQ1 is an oncogenic transcription factor that is overexpressed in basal-like and luminal-type human breast cancers when compared to the normal mammary tissue. The FoxQ1 is implicated in mammary tumor progression. However, the mechanism by which FoxQ1 promotes mammary tumorigenesis is not fully understood. In this study, we present experimental evidence for a novel function of FoxQ1 in the regulation of complex I activity of the electron transport chain. The RNA-seq data from FoxQ1 overexpressing basal-like SUM159 cells revealed a statistically significant increase in the expression of complex I subunits NDUFS1 and NDUFS2 when compared to the empty vector (EV) transfected control cells. Consistent with these results, the basal and ATP-linked oxygen consumption rates were significantly increased by FoxQ1 overexpression in SUM159 and luminal-type MCF-7 cells. The FoxQ1 overexpression in both cell lines resulted in increased intracellular levels of pyruvate, lactate, and ATP that was associated with overexpression of pyruvate dehydrogenase and pyruvate carboxylase proteins. Activity and assembly of complex I were significantly enhanced by FoxQ1 overexpression in SUM159 and MCF-7 cells that correlated with increased mRNA and/or protein levels of complex I subunits NDUFS1, NDUFS2, NDUFV1, and NDUFV2. The chromatin immunoprecipitation assay revealed the recruitment of FoxQ1 at the promoters of both NDUFS1 and NDUFV1. The cell proliferation of SUM159 and MCF-7 cells was increased significantly by overexpression of NDUFS1 as well as NDUFV1 proteins. In conclusion, we propose that increased complex I-linked oxidative phosphorylation is partly responsible for oncogenic role of FoxQ1 at least in human breast cancer cells.
Topics: Adenosine Triphosphate; Breast Neoplasms; Electron Transport; Electron Transport Complex I; Female; Forkhead Transcription Factors; Gene Expression Regulation, Neoplastic; Humans; Pyruvic Acid
PubMed: 34939230
DOI: 10.1002/mc.23381 -
Stem Cell Research & Therapy Jan 2021Mesenchymal stem cell (MSC)-based therapy has the potential for immunomodulation and enhancement of tissue regeneration. Genetically modified MSCs that over-express...
BACKGROUND
Mesenchymal stem cell (MSC)-based therapy has the potential for immunomodulation and enhancement of tissue regeneration. Genetically modified MSCs that over-express specific cytokines, growth factors, or chemokines have shown great promise in pre-clinical studies. In this regard, the anti-inflammatory cytokine interleukin (IL)-4 converts pro-inflammatory M1 macrophages into an anti-inflammatory M2 phenotype; M2 macrophages mitigate chronic inflammation and enhance osteogenesis by MSC lineage cells. However, exposure to IL-4 prematurely inhibits osteogenesis of MSCs in vitro; furthermore, IL-4 overexpressing MSCs inhibit osteogenesis in vivo during the acute inflammatory period. Platelet-derived growth factor (PDGF)-BB has been shown to enhance osteogenesis of MSCs with a dose-dependent effect.
METHODS
In this study, we generated a lentiviral vector that produces PDGF-BB under a weak promoter (phosphoglycerate kinase, PGK) and lentiviral vector producing IL-4 under a strong promoter (cytomegalovirus, CMV). We infected MSCs with PDGF-BB and IL-4-producing lentiviral vectors separately or in combination to investigate cell proliferation and viability, protein expression, and the capability for osteogenesis.
RESULTS
PDGF-BB and IL-4 co-overexpression was observed in the co-infected MSCs and shown to enhance cell proliferation and viability, and osteogenesis compared to IL-4 overexpressing MSCs alone.
CONCLUSIONS
Overexpression of PDGF-BB together with IL-4 mitigates the inhibitory effect of IL-4 on osteogenesis by IL-4 overexpressing MSCS. PDGF-BB and IL-4 overexpressing MSCs may be a potential strategy to facilitate osteogenesis in scenarios of both acute and chronic inflammation.
Topics: Becaplermin; Bone Regeneration; Interleukin-4; Mesenchymal Stem Cells; Osteogenesis
PubMed: 33413614
DOI: 10.1186/s13287-020-02086-8 -
Biological & Pharmaceutical Bulletin 2023Phosphatidylinositol-4-phosphate 5-kinase (PI4P5K) is a highly conserved enzyme that generates phosphatidylinositol-4,5-bisphosphate (PI(4,5)P) by phosphorylating...
Phosphatidylinositol-4-phosphate 5-kinase (PI4P5K) is a highly conserved enzyme that generates phosphatidylinositol-4,5-bisphosphate (PI(4,5)P) by phosphorylating phosphatidylinositol 4-phosphate (PI(4)P). Schizosaccharomyces pombe (S. pombe) its3-1 is a loss-of-function mutation in the essential its3 gene that encodes a PI4P5K. Its3 regulates cell proliferation, cytokinesis, cell integrity, and membrane trafficking, but little is known about the regulatory mechanisms of Its3. To identify regulators of Its3, we performed a genetic screening utilizing the high-temperature sensitivity (TS) of its3-1 and identified puf3 and puf4, encoding Pumilio/PUF family RNA-binding proteins as multicopy suppressors of its3-1 cells. The deletions of the PUF domains in the puf3 and puf4 genes resulted in the reduced ability to suppress its3-1, suggesting that the suppression by Puf3 and Puf4 may involve their RNA-binding activities. The gene knockout of Puf4, but not that of Puf3, exacerbated the TS of its3-1. Interestingly, mutant Its3 expression levels both at mRNA and protein levels were lower than those of the wild-type (WT) Its3. Consistently, the overexpression of the mutant its3-1 gene suppressed the its3-1 phenotypes. Notably, Puf3 and Puf4 overexpression increased the mRNA and protein expression levels of both Its3 and Its3-1. Collectively, our genetic screening revealed a functional relationship between the Pumilio/PUF family RNA-binding proteins and PI4P5K.
Topics: RNA, Messenger; RNA-Binding Proteins; Schizosaccharomyces; Schizosaccharomyces pombe Proteins
PubMed: 36724944
DOI: 10.1248/bpb.b22-00569