39 research outputs found

    Evolution of monkeypox virus from 2017 to 2022: In the light of point mutations

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    Monkeypox virus (MPXV) causing multi-country outbreak-2022 is related to viruses caused outbreak-2017–2018 in West Africa. Still not fully understood which proteins of the MPXV discovered in Nigeria in 2017 have mutated through different lineages to the extent that it could cause a multi-country outbreak in 2022; similarly, codon usage bias, host adaptation indices, and the role of selection or mutation pressure in the mutated genes are also not fully studied. Here we report that according to the available sequence data this monkeypox virus acquires point mutations in multiple proteins in each period, and these point mutations accumulate and become a virus that can root outbreak-2022. Viruses exported from Nigeria to Singapore, Israel, and the United Kingdom in 2018–2019 were developed as evolutionary ancestors to B.1 viruses (MPXVs causing multi-country outbreak-2022) through MPXV/United States/2021/MD virus. Although these exported viruses have different amino acid mutations in different proteins, amino acid mutations in 10 proteins are common among them. The MPXV-United Kingdom-P2 virus evolved with only mutations in these 10 proteins and further evolved into MPXV/United States/2021/MD with amino acid mutations in 26 (including amino acid mutations in 10 proteins of the MPXV-United States-P2) proteins. It is noteworthy that specific amino acid mutations in these 22/26 (presence in MPXV/United States/2021/MD) proteins are present in B.1 viruses. Further, analysis of Relative Synonymous Codon Usage (RSCU), Synonymous Codon Usage Fraction (SCUF), and Effective Number of Codons (ENc) revealed codon usage bias in genes that exhibited nucleotide mutations in lineage B.1. Also, host adaptation indices analyzes such as Codon Adaptation Index (CAI), Expected-CAI (eCAI), Relative Codon Deoptimization Index (RCDI) and Expected value for the RCDI (eRCDI) analyzes reveal that the genes that demonstrated nucleotide mutations in lineage B.1 are favorable for human adaptation. Similarly, ENc-GC3s plot, Neutrality plot, and Parity Rule 2 (PR2)-bias plot analyzes suggest a major role of selection pressure than mutation pressure in the evolution of genes displaying nucleotide mutations in lineage B.1. Overall, from 2017 to 2022, MPXV’s mutation and spread suggests that this virus continues to evolve through point mutation in the genes according to the available sequence data

    SIRT3 Deacetylates and Activates OPA1 To Regulate Mitochondrial Dynamics during Stress

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    Mitochondrial morphology is regulated by the balance between two counteracting mitochondrial processes of fusion and fission. There is significant evidence suggesting a stringent association between morphology and bioenergetics of mitochondria. Morphological alterations in mitochondria are linked to several pathological disorders, including cardiovascular diseases. The consequences of stress-induced acetylation of mitochondrial proteins on the organelle morphology remain largely unexplored. Here we report that OPA1, a mitochondrial fusion protein, was hyperacetylated in hearts under pathological stress and this posttranslational modification reduced the GTPase activity of the protein. The mitochondrial deacetylase SIRT3 was capable of deacetylating OPA1 and elevating its GTPase activity. Mass spectrometry and mutagenesis analyses indicated that in SIRT3-deficient cells OPA1 was acetylated at lysine 926 and 931 residues. Overexpression of a deacetylation-mimetic version of OPA1 recovered the mitochondrial functions of OPA1-null cells, thus demonstrating the functional significance of K926/931 acetylation in regulating OPA1 activity. Moreover, SIRT3-dependent activation of OPA1 contributed to the preservation of mitochondrial networking and protection of cardiomyocytes from doxorubicin-mediated cell death. In summary, these data indicated that SIRT3 promotes mitochondrial function not only by regulating activity of metabolic enzymes, as previously reported, but also by regulating mitochondrial dynamics by targeting OPA1

    Sirtuin 6 inhibition protects against glucocorticoid-induced skeletal muscle atrophy by regulating IGF/PI3K/AKT signaling

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    Chronic activation of stress hormones such as glucocorticoids leads to skeletal muscle wasting in mammals. However, the molecular events that mediate glucocorticoid-induced muscle wasting are not well understood. Here, we show that SIRT6, a chromatin-associated deacetylase indirectly regulates glucocorticoid-induced muscle wasting by modulating IGF/PI3K/AKT signaling. Our results show that SIRT6 levels are increased during glucocorticoid-induced reduction of myotube size and during skeletal muscle atrophy in mice. Notably, overexpression of SIRT6 spontaneously decreases the size of primary myotubes in a cell-autonomous manner. On the other hand, SIRT6 depletion increases the diameter of myotubes and protects them against glucocorticoid-induced reduction in myotube size, which is associated with enhanced protein synthesis and repression of atrogenes. In line with this, we find that muscle-specific SIRT6 deficient mice are resistant to glucocorticoid-induced muscle wasting. Mechanistically, we find that SIRT6 deficiency hyperactivates IGF/PI3K/AKT signaling through c-Jun transcription factor-mediated increase in IGF2 expression. The increased activation, in turn, leads to nuclear exclusion and transcriptional repression of the FoxO transcription factor, a key activator of muscle atrophy. Further, we find that pharmacological inhibition of SIRT6 protects against glucocorticoid-induced muscle wasting in mice by regulating IGF/PI3K/AKT signaling implicating the role of SIRT6 in glucocorticoid-induced muscle atrophy.Fil: Mishra, Sneha. No especifíca;Fil: Cosentino, Claudia. Harvard Medical School; Estados UnidosFil: Tamta, Ankit Kumar. No especifíca;Fil: Khan, Danish. No especifíca;Fil: Srinivasan, Shalini. No especifíca;Fil: Ravi, Venkatraman. No especifíca;Fil: Abbotto, Elena. Università degli Studi di Genova; ItaliaFil: Arathi, Bangalore Prabhashankar. No especifíca;Fil: Kumar, Shweta. No especifíca;Fil: Jain, Aditi. No especifíca;Fil: Ramaian, Anand S.. No especifíca;Fil: Kizkekra, Shruti M.. No especifíca;Fil: Rajagopal, Raksha. No especifíca;Fil: Rao, Swathi. No especifíca;Fil: Krishna, Swati. No especifíca;Fil: Asirvatham Jeyaraj, Ninitha. Indian Institute of Technology; IndiaFil: Haggerty, Elizabeth R.. Harvard Medical School; Estados UnidosFil: Silberman, Dafne Magalí. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Estudios Farmacológicos y Botánicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios Farmacológicos y Botánicos; ArgentinaFil: Kurland, Irwin J.. No especifíca;Fil: Veeranna, Ravindra P.. No especifíca;Fil: Jayavelu, Tamilselvan. No especifíca;Fil: Bruzzone, Santina. Università degli Studi di Genova; ItaliaFil: Mostoslavsky, Raul. Harvard Medical School; Estados UnidosFil: Sundaresan, Nagalingam R.. No especifíca

    Deciphering the Origin of DNA Viruses (Replication-Associated Parvo-NS1) That Infect Vertebrates from Invertebrate-Infecting Viruses

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    ABSTRACT DNA replication is a standard and essential function among DNA viruses; however, this functional domain's common ancestor, origin, and evolutionary path in invertebrate- and vertebrate-infecting viruses are not yet fully understood. Here, we present evidence, using a combination of phylogenetic relationships, coevolution, and CLANS (cluster analysis of sequences) analysis, that the parvo-NS1 domain (nonstructural protein NS1, DNA helicase domain) of these DNA viruses that infect vertebrates potentially originated from the invertebrate (Platyhelminthes) parvo-NS1 domain of parvovirus-related sequences (PRSs). Our results suggest that papillomaviruses and the parvovirus subfamilies Densovirinae and Hamaparvovirinae DNA helicase evolved directly from the Platyhelminthes NS1 domain (PRSs). Similarly, the parvovirus subfamily Parvovirinae NS1 domain displayed evolutionary heritage from the PRSs through Hamaparvovirinae. Further, our analysis also clarified that herpesviruses and adenoviruses independently obtained the parvo-NS1 domain from Dependoparvovirus (Parvovirinae). Furthermore, virus-host coevolution analysis revealed that the parvovirus NS1 domain has coevolved with hosts, from flatworms to humans, and it appears that the papillomavirus may have obtained the DNA helicase during the early stages of parvovirus evolution and later led to the development of the DNA helicase of adomavirus and polyomavirus. Finally, herpesviruses and adenoviruses likely inherited the parvo-NS1 domain from Dependoparvovirus in the later stages of evolution. To the best of our knowledge, this is the first evolutionary evidence to suggest that the DNA helicase of viruses that infect vertebrates originated from the invertebrate PRSs. IMPORTANCE DNA replication of DNA viruses is an essential function. This allows DNA replication of viruses to form virus particles. The DNA helicase domain is responsible for this primary function. This domain is present in parvoviruses, papillomaviruses, polyomaviruses, herpesviruses, and adenoviruses. But little is known about the common ancestor, origin, and evolutionary path of DNA helicase in invertebrate- and vertebrate-infecting viruses. Here, we report the possibility of the origin of DNA viruses (DNA helicase) infecting vertebrates from Platyhelminthes (invertebrate) PRSs. Our study established that the parvovirus subfamily Parvovirinae NS1 domain displayed evolutionary heritage from the Platyhelminthes PRSs through Hamaparvovirinae. Furthermore, our study suggests that the papillomavirus DNA helicase may have evolved in the early stages of parvovirus evolution and then led to the development of the adomavirus and polyomavirus. Our study suggests that the herpesviruses and adenoviruses likely inherited the parvo-NS1 domain through gene capture from Dependoparvovirus in the later stages of parvovirus evolution in their hosts

    Engineering an in vitro organotypic model for studying cardiac hypertrophy

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    Neonatal cardiomyocytes cultured on flat surfaces are commonly used as a model to study cardiac failure of diverse origin. A major drawback of such a system is that the cardiomyocytes do not exhibit alignment, organization and calcium transients, similar to the native heart. Therefore, there is a need to develop in vitro platforms that recapitulate the cellular microenvironment of the murine heart as organotypic models to study cardiovascular diseases. In this study, we report an engineered platform that mimics cardiac cell organization and function of the heart. For this purpose, microscale ridges were fabricated on silicon using ultraviolet lithography and reactive ion etching techniques. Physical characterization of the microstructures was done using scanning electron microscopy and atomic force microscopy. Cardiomyocytes grown on these micro-ridges showed global parallel alignment and elliptical nuclear morphology as observed in the heart. Interestingly, calcium currents traversed the engineered cardiomyocytes in a coordinated and directional manner. Moreover, the cardiomyocytes on the engineered substrates were found to be responsive to hypertrophic stimuli, as observed by the expression of a fetal gene, atrial natriuretic peptide and increase in calcium transients upon agonist treatment. Taken together, our work demonstrates that micro-ridges can be used to obtain cardiomyocyte response in vitro, which closely resembles mammalian heart. (C) 2018 Elsevier B.V. All rights reserved

    Image_1_Evolution of monkeypox virus from 2017 to 2022: In the light of point mutations.TIF

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    Monkeypox virus (MPXV) causing multi-country outbreak-2022 is related to viruses caused outbreak-2017–2018 in West Africa. Still not fully understood which proteins of the MPXV discovered in Nigeria in 2017 have mutated through different lineages to the extent that it could cause a multi-country outbreak in 2022; similarly, codon usage bias, host adaptation indices, and the role of selection or mutation pressure in the mutated genes are also not fully studied. Here we report that according to the available sequence data this monkeypox virus acquires point mutations in multiple proteins in each period, and these point mutations accumulate and become a virus that can root outbreak-2022. Viruses exported from Nigeria to Singapore, Israel, and the United Kingdom in 2018–2019 were developed as evolutionary ancestors to B.1 viruses (MPXVs causing multi-country outbreak-2022) through MPXV/United States/2021/MD virus. Although these exported viruses have different amino acid mutations in different proteins, amino acid mutations in 10 proteins are common among them. The MPXV-United Kingdom-P2 virus evolved with only mutations in these 10 proteins and further evolved into MPXV/United States/2021/MD with amino acid mutations in 26 (including amino acid mutations in 10 proteins of the MPXV-United States-P2) proteins. It is noteworthy that specific amino acid mutations in these 22/26 (presence in MPXV/United States/2021/MD) proteins are present in B.1 viruses. Further, analysis of Relative Synonymous Codon Usage (RSCU), Synonymous Codon Usage Fraction (SCUF), and Effective Number of Codons (ENc) revealed codon usage bias in genes that exhibited nucleotide mutations in lineage B.1. Also, host adaptation indices analyzes such as Codon Adaptation Index (CAI), Expected-CAI (eCAI), Relative Codon Deoptimization Index (RCDI) and Expected value for the RCDI (eRCDI) analyzes reveal that the genes that demonstrated nucleotide mutations in lineage B.1 are favorable for human adaptation. Similarly, ENc-GC3s plot, Neutrality plot, and Parity Rule 2 (PR2)-bias plot analyzes suggest a major role of selection pressure than mutation pressure in the evolution of genes displaying nucleotide mutations in lineage B.1. Overall, from 2017 to 2022, MPXV’s mutation and spread suggests that this virus continues to evolve through point mutation in the genes according to the available sequence data.</p

    A nanopillar array on black titanium prepared by reactive ion etching augments cardiomyogenic commitment of stem cells

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    A major impediment in the clinical translation of stem cell therapy has been the inability to efficiently and reproducibly direct differentiation of a large population of stem cells. Thus, we aimed to engineer a substrate for culturing stem cells to efficiently induce cardiomyogenic lineage commitment. In this work, we present a nanopillar array on the surface of titanium that was prepared by mask-less reactive ion etching. Scanning electron and atomic force microscopy revealed that the surface was covered by vertically aligned nanopillars each of approximate to 1 mu m with a diameter of approximate to 80 nm. The nanopillars supported the attachment and proliferation of human mesenchymal stem cells (hMSCs). Cardiomyogenic lineage commitment of the stem cells was more enhanced on the nanopillars than on the smooth surface. When co-cultured with neonatal rat cardiomyocytes, the cyclic pattern of calcium transport observed distinctly in cells differentiated on the arrays compared to the cells cultured on the smooth surface was the functional validation of differentiation. The use of small molecule inhibitors revealed that integrins namely, alpha(2)beta(1) and alpha(v)beta(3), are essential for cardiomyogenesis on the nanostructured surface, which is further mediated by FAK, Erk and Akt cell signaling pathways. This study demonstrates that the nanopillar array efficiently promotes the cardiomyogenic lineage commitment of stem cells via integrin-mediated signaling and can potentially serve as a platform for the ex vivo differentiation of stem cells toward cell therapy in cardiac tissue repair and regeneration

    Table_3_Evolution of monkeypox virus from 2017 to 2022: In the light of point mutations.XLSX

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    Monkeypox virus (MPXV) causing multi-country outbreak-2022 is related to viruses caused outbreak-2017–2018 in West Africa. Still not fully understood which proteins of the MPXV discovered in Nigeria in 2017 have mutated through different lineages to the extent that it could cause a multi-country outbreak in 2022; similarly, codon usage bias, host adaptation indices, and the role of selection or mutation pressure in the mutated genes are also not fully studied. Here we report that according to the available sequence data this monkeypox virus acquires point mutations in multiple proteins in each period, and these point mutations accumulate and become a virus that can root outbreak-2022. Viruses exported from Nigeria to Singapore, Israel, and the United Kingdom in 2018–2019 were developed as evolutionary ancestors to B.1 viruses (MPXVs causing multi-country outbreak-2022) through MPXV/United States/2021/MD virus. Although these exported viruses have different amino acid mutations in different proteins, amino acid mutations in 10 proteins are common among them. The MPXV-United Kingdom-P2 virus evolved with only mutations in these 10 proteins and further evolved into MPXV/United States/2021/MD with amino acid mutations in 26 (including amino acid mutations in 10 proteins of the MPXV-United States-P2) proteins. It is noteworthy that specific amino acid mutations in these 22/26 (presence in MPXV/United States/2021/MD) proteins are present in B.1 viruses. Further, analysis of Relative Synonymous Codon Usage (RSCU), Synonymous Codon Usage Fraction (SCUF), and Effective Number of Codons (ENc) revealed codon usage bias in genes that exhibited nucleotide mutations in lineage B.1. Also, host adaptation indices analyzes such as Codon Adaptation Index (CAI), Expected-CAI (eCAI), Relative Codon Deoptimization Index (RCDI) and Expected value for the RCDI (eRCDI) analyzes reveal that the genes that demonstrated nucleotide mutations in lineage B.1 are favorable for human adaptation. Similarly, ENc-GC3s plot, Neutrality plot, and Parity Rule 2 (PR2)-bias plot analyzes suggest a major role of selection pressure than mutation pressure in the evolution of genes displaying nucleotide mutations in lineage B.1. Overall, from 2017 to 2022, MPXV’s mutation and spread suggests that this virus continues to evolve through point mutation in the genes according to the available sequence data.</p

    Table_5_Evolution of monkeypox virus from 2017 to 2022: In the light of point mutations.XLSX

    No full text
    Monkeypox virus (MPXV) causing multi-country outbreak-2022 is related to viruses caused outbreak-2017–2018 in West Africa. Still not fully understood which proteins of the MPXV discovered in Nigeria in 2017 have mutated through different lineages to the extent that it could cause a multi-country outbreak in 2022; similarly, codon usage bias, host adaptation indices, and the role of selection or mutation pressure in the mutated genes are also not fully studied. Here we report that according to the available sequence data this monkeypox virus acquires point mutations in multiple proteins in each period, and these point mutations accumulate and become a virus that can root outbreak-2022. Viruses exported from Nigeria to Singapore, Israel, and the United Kingdom in 2018–2019 were developed as evolutionary ancestors to B.1 viruses (MPXVs causing multi-country outbreak-2022) through MPXV/United States/2021/MD virus. Although these exported viruses have different amino acid mutations in different proteins, amino acid mutations in 10 proteins are common among them. The MPXV-United Kingdom-P2 virus evolved with only mutations in these 10 proteins and further evolved into MPXV/United States/2021/MD with amino acid mutations in 26 (including amino acid mutations in 10 proteins of the MPXV-United States-P2) proteins. It is noteworthy that specific amino acid mutations in these 22/26 (presence in MPXV/United States/2021/MD) proteins are present in B.1 viruses. Further, analysis of Relative Synonymous Codon Usage (RSCU), Synonymous Codon Usage Fraction (SCUF), and Effective Number of Codons (ENc) revealed codon usage bias in genes that exhibited nucleotide mutations in lineage B.1. Also, host adaptation indices analyzes such as Codon Adaptation Index (CAI), Expected-CAI (eCAI), Relative Codon Deoptimization Index (RCDI) and Expected value for the RCDI (eRCDI) analyzes reveal that the genes that demonstrated nucleotide mutations in lineage B.1 are favorable for human adaptation. Similarly, ENc-GC3s plot, Neutrality plot, and Parity Rule 2 (PR2)-bias plot analyzes suggest a major role of selection pressure than mutation pressure in the evolution of genes displaying nucleotide mutations in lineage B.1. Overall, from 2017 to 2022, MPXV’s mutation and spread suggests that this virus continues to evolve through point mutation in the genes according to the available sequence data.</p
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