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1.
Phlebology ; 39(1): 20-28, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37846077

RESUMO

INTRODUCTION: Although morphological and anatomical studies indicate that venous wall weakening and subendothelial fibrosis characterize varicose veins (VV), the pathogenesis of VV remains poorly understood. The aim of this study is to obtain protein expression profiles in patients with VV and thereby get a step closer to understanding the pathogenesis of VV. METHODS: Specimens were obtained from total of 10 patients, that is, from 5 patients undergoing VV surgical stripping and from 5 non-VV patients undergoing bypass surgery. Specimens were collected from the same layers of venous wall. Proteins were extracted from each specimen and analyzed by ion mobility spectrometry (IMS-MS). In total, 1387 were identified and 486 proteins were identified in all samples. From these, 15 proteins were differentially expressed between VV and non-VV samples (p < .05) and 12 of these showed a fold change >1.5. RESULTS: Interestingly, among the differentially expressed proteins, only two proteins were significantly increased in the VV tissue, that is, GAPDH (p = .028, fold change 2.74), where several proteins involved in maintaining the homeostasis in the extracellular matrix, that is, the CXXC zinc finger protein 5 (CXXC5) and nucleoporin (SEH1) were prominently downregulated (p = .049, fold change 37.8, and p = .040, fold change 3.46). The downregulation in protein expression of CXXC5 and SEH1 as well as upregulation of GAPDH were validated by Western blotting. CONCLUSION: The identified differentially expressed proteins suggest an altered profile of the connective tissue proteins as well as an increased proteolytic enzyme activity which both may be central in the pathophysiology of varicose veins.


Assuntos
Proteômica , Varizes , Humanos , Veia Safena/patologia , Varizes/cirurgia , Procedimentos Cirúrgicos Vasculares , Matriz Extracelular/metabolismo , Matriz Extracelular/patologia , Proteínas de Ligação a DNA/análise , Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição/análise , Fatores de Transcrição/metabolismo
2.
Int J Mol Sci ; 24(18)2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37762288

RESUMO

A high temperature-adapted bacteriophage, vB_PtoS_NIIg3.2 (NIIg3.2), was isolated in Lithuania from compost heaps using Parageobacillus toebii strain NIIg-3 as a host for phage propagation. Furthermore, NIIg3.2 was active against four strains of Geobacillus thermodenitrificans, and it infected the host cells from 50 to 80 °C. Transmission electron microscopy analysis revealed siphovirus morphology characterized by an isometric head (~59 nm in diameter) and a noncontractile tail (~226 nm in length). The double-stranded DNA genome of NIIg3.2 (38,970 bp) contained 71 probable protein-encoding genes and no genes for tRNA. In total, 29 NIIg3.2 ORFs were given a putative functional annotation, including those coding for the proteins responsible for DNA packaging, virion structure/morphogenesis, phage-host interactions, lysis/lysogeny, replication/regulation, and nucleotide metabolism. Based on comparative phylogenetic and bioinformatic analysis, NIIg3.2 cannot be assigned to any genus currently recognized by ICTV and potentially represents a new one within siphoviruses. The results of this study not only extend our knowledge about poorly explored thermophilic bacteriophages but also provide new insights for further investigation and understanding the evolution of Bacilllus-group bacteria-infecting viruses.


Assuntos
Bacteriófagos , Bacteriófagos/genética , Filogenia , Lisogenia , Técnicas de Tipagem Bacteriana , Morte Celular
3.
mSystems ; 8(5): e0071823, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37706681

RESUMO

IMPORTANCE: Non-canonical 5'-caps removing RNA hydrolase NudC, along with stress-responsive RNA helicase CsdA, is crucial for 5'-NAD-RNA decapping and bacterial movement.


Assuntos
Escherichia coli , NAD , Escherichia coli/genética , Hidrolases , RNA Helicases DEAD-box/genética , RNA
4.
Viruses ; 15(8)2023 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-37632033

RESUMO

We report a detailed characterization of five thermophilic bacteriophages (phages) that were isolated from compost heaps in Vilnius, Lithuania using Geobacillus thermodenitrificans strains as the hosts for phage propagation. The efficiency of plating experiments revealed that phages formed plaques from 45 to 80 °C. Furthermore, most of the phages formed plaques surrounded by halo zones, indicating the presence of phage-encoded bacterial exopolysaccharide (EPS)-degrading depolymerases. Transmission Electron Microscopy (TEM) analysis revealed that all phages were siphoviruses characterized by an isometric head (from ~63 nm to ~67 nm in diameter) and a non-contractile flexible tail (from ~137 nm to ~150 nm in length). The genome sequencing resulted in genomes ranging from 38,161 to 39,016 bp. Comparative genomic and phylogenetic analysis revealed that all the isolated phages had no close relatives to date, and potentially represent three new genera within siphoviruses. The results of this study not only improve our knowledge about poorly explored thermophilic bacteriophages but also give new insights for further investigation of thermophilic and/or thermostable enzymes of bacterial viruses.


Assuntos
Bacteriófagos , Compostagem , Geobacillus , Filogenia , Técnicas de Tipagem Bacteriana , Bacteriófagos/genética , Geobacillus/genética
5.
Int J Mol Sci ; 24(3)2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36768772

RESUMO

The prevalence of infertility is getting higher over the years. The increasing age of first-time parents, although economically more desirable, can cause various biological problems from low natural conception rate to poor pregnancy outcomes. The growing demand for assisted reproductive technology procedures worldwide draws medical specialists' and scientists' attention to various elements which could lead to successful conception, such as follicular fluid (FF) and hormones. In this study, we analyzed the effects of exposure to follicle-stimulating hormone (FSH) on FF-derived stromal cells isolated from females admitted for treatment due to infertility, participating in assisted reproductive technologies procedures. We demonstrated that FF stromal cells are positive for mesenchymal stromal cell surface markers (CD90+, CD44+, CD166+) and showed that FSH has no impact on FF stromal cell morphology yet lowers proliferation rate. Using a real-time polymerase chain reaction method, we indicated that the expression of PTGS2 is significantly downregulated in FF sediment cells of patients who did not conceive; furthermore, we showed that FSH can affect the expression of ovarian follicle development and FSH response-related genes differentially depending on the length of exposure and that levels of ovulatory cascade genes differ in conceived and not-conceived patients' FF stromal cells. Using mass spectrometry analysis, we identified 97 proteins secreted by FF stromal cells. The identified proteins are related to stress response, positive regulation of apoptotic cell clearance and embryo implantation.


Assuntos
Hormônio Foliculoestimulante , Infertilidade , Gravidez , Feminino , Humanos , Hormônio Foliculoestimulante/farmacologia , Hormônio Foliculoestimulante/metabolismo , Líquido Folicular/metabolismo , Folículo Ovariano/metabolismo , Hormônio Foliculoestimulante Humano , Infertilidade/metabolismo , Células Estromais/metabolismo
6.
Int J Mol Sci ; 23(16)2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-36012768

RESUMO

Lytic viruses of bacteria (bacteriophages, phages) are intracellular parasites that take over hosts' biosynthetic processes for their propagation. Most of the knowledge on the host hijacking mechanisms has come from the studies of the lytic phage T4, which infects Escherichia coli. The integrity of T4 development is achieved by strict control over the host and phage processes and by adjusting them to the changing infection conditions. In this study, using in vitro and in vivo biochemical methods, we detected the direct interaction between the T4 protein RIII and ribosomal protein S1 of the host. Protein RIII is known as a cytoplasmic antiholin, which plays a role in the lysis inhibition function of T4. However, our results show that RIII also acts as a viral effector protein mainly targeting S1 RNA-binding domains that are central for all the activities of this multifunctional protein. We confirm that the S1-RIII interaction prevents the S1-dependent activation of endoribonuclease RegB. In addition, we propose that by modulating the multiple processes mediated by S1, RIII could act as a regulator of all stages of T4 infection including the lysis inhibition state.


Assuntos
Bacteriófago T4 , Endorribonucleases , Endorribonucleases/metabolismo , Escherichia coli/metabolismo , Proteínas Ribossômicas/metabolismo , Proteínas Virais/metabolismo
7.
Front Genet ; 13: 821676, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35495123

RESUMO

Acute myeloid leukemia (AML) is an aggressive, heterogeneous group of malignancies with different clinical behaviors and different responses to therapy. For many types of cancer, finding cancer early makes it easier to treat. Identifying prognostic molecular markers and understanding their biology are the first steps toward developing novel diagnostic tools or therapies for patients with AML. In this study, we defined proteins and genes that can be used in the prognosis of different acute leukemia cases and found possible uses in diagnostics and therapy. We analyzed newly diagnosed acute leukemia cases positive for t (15; 17) (q22; q21) PML-RAR alpha, acute promyelocytic leukemia (APL). The samples of bone marrow cells were collected from patients at the diagnosis stage, as follow-up samples during standard treatment with all-trans retinoic acid, idarubicin, and mitoxantrone, and at the molecular remission. We determined changes in the expression of genes involved in leukemia cell growth, apoptosis, and differentiation. We observed that WT1, CALR, CAV1, and MYC genes' expression in all APL patients with no relapse history was downregulated after treatment and could be potential markers associated with the pathology, thereby revealing the potential value of this approach for a better characterization of the prediction of APL outcomes.

8.
ACS Appl Mater Interfaces ; 13(33): 39076-39087, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34378375

RESUMO

Fluorophores with multifunctional properties known as rare-earth-doped nanoparticles (RENPs) are promising candidates for bioimaging, therapy, and drug delivery. When applied in vivo, these nanoparticles (NPs) have to retain long blood-circulation time, bypass elimination by phagocytic cells, and successfully arrive at the target area. Usually, NPs in a biological medium are exposed to proteins, which form the so-called "protein corona" (PC) around the NPs and influence their targeted delivery and accumulation in cells and tissues. Different surface coatings change the PC size and composition, subsequently deciding the fate of the NPs. Thus, detailed studies on the PC are of utmost importance to determine the most suitable NP surface modification for biomedical use. When it comes to RENPs, these studies are particularly scarce. Here, we investigate the PC composition and its impact on the cellular uptake of citrate-, SiO2-, and phospholipid micelle-coated RENPs (LiYF4:Yb3+,Tm3+). We observed that the PC of citrate- and phospholipid-coated RENPs is relatively stable and similar in the adsorbed protein composition, while the PC of SiO2-coated RENPs is larger and highly dynamic. Moreover, biocompatibility, accumulation, and cytotoxicity of various RENPs in cancer cells have been evaluated. On the basis of the cellular imaging, supported by the inhibition studies, it was revealed that RENPs are internalized by endocytosis and that specific endocytic routes are PC composition dependent. Overall, these results are essential to fill the gaps in the fundamental understanding of the nano-biointeractions of RENPs, pertinent for their envisioned application in biomedicine.


Assuntos
Materiais Revestidos Biocompatíveis/química , Corantes Fluorescentes/química , Compostos de Lítio/química , Nanopartículas Metálicas/química , Coroa de Proteína/metabolismo , Dióxido de Silício/química , Ítrio/química , Adsorção , Neoplasias da Mama , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular , Ácido Cítrico/química , Materiais Revestidos Biocompatíveis/metabolismo , Endocitose , Corantes Fluorescentes/metabolismo , Humanos , Tamanho da Partícula , Fosfolipídeos/química , Propriedades de Superfície
9.
Int J Mol Sci ; 22(13)2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202508

RESUMO

When looking for the causes and treatments of infertility, much attention is paid to one of the reproductive tissues-the endometrium. Therefore, endometrial stem cells are an attractive target for infertility studies in women of unexplained origin. Menstrual blood stem cells (MenSCs) are morphologically and functionally similar to cells derived directly from the endometrium; with dual expression of mesenchymal and embryonic cell markers, they proliferate and regenerate better than bone marrow mesenchymal stem cells. In addition, menstrual blood stem cells are extracted in a non-invasive and painless manner. In our study, we analyzed the characteristics and the potential for decidualization of menstrual blood stem cells isolated from healthy volunteers and women diagnosed with infertility. We demonstrated that MenSCs express CD44, CD166, CD16, CD15, BMSC, CD56, CD13 and HLA-ABC surface markers, have proliferative properties, and after induction of menstrual stem cell differentiation into epithelial direction, expression of genes related to decidualization (PRL, ESR, IGFBP and FOXO1) and angiogenesis (HIF1, VEGFR2 and VEGFR3) increased. Additionally, the p53, p21, H3K27me3 and HyperAcH4 proteins' expression increased during MenSCs decidualization, they secrete proteins that are involved in the regulation of the actin cytoskeleton, estrogen and relaxin signaling pathways and the management of inflammatory processes. Our findings reveal the potential use of MenSCs for the treatment of reproductive disorders.


Assuntos
Endométrio/citologia , Infertilidade Feminina/terapia , Menstruação , Transplante de Células-Tronco , Células-Tronco/citologia , Células-Tronco/metabolismo , Biomarcadores , Diferenciação Celular , Proliferação de Células , Separação Celular/métodos , Células Cultivadas , Decídua/citologia , Decídua/metabolismo , Feminino , Humanos , Imunofenotipagem , Infertilidade Feminina/etiologia , Proteoma , Proteômica/métodos
10.
Life (Basel) ; 11(6)2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34207784

RESUMO

Survival rates from pancreatic cancer have remained stagnant for decades due to the heterogenic nature of the disease. This study aimed to find a new advanced biomarker and evaluate its clinical capabilities, thus enabling more individualised pancreatic cancer management. Between 2013 and 2020, 267 patients were included in the study. Surgically collected pancreatic tissue samples were analysed via high-definition mass spectrometry. Carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6) was discovered as a possible promising pancreatic cancer biomarker. The predominance of CEACAM6 to pancreatic cancer was validated using antibodies in tissue samples. CEACAM6, carbohydrate antigen 19-9 (CA19-9), and carcinoembryonic antigen (CEA) blood serum concentrations were evaluated for clinical evaluation and comparison. Kaplan-Meier survival analyses were used to evaluate disease-free survival (DFS) and overall survival (OS). Poorer overall survival was significantly dependent on increased CEACAM6 blood serum concentrations (17.0 vs. 12.6 months, p = 0.017) in pancreatic cancer patients after radical treatment and adjuvant chemotherapy. Increased CEA and CA19-9 concentrations showed no significant dependencies with survival. Thus, CEACAM6 is a promising new biomarker with significant prognostic value and prediction of chemoresistance properties, enabling the improvement of individualised approaches to patients with pancreatic cancer.

11.
Int J Mol Sci ; 22(14)2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34298953

RESUMO

A novel siphovirus, vB_PagS_MED16 (MED16) was isolated in Lithuania using Pantoea agglomerans strain BSL for the phage propagation. The double-stranded DNA genome of MED16 (46,103 bp) contains 73 predicted open reading frames (ORFs) encoding proteins, but no tRNA. Our comparative sequence analysis revealed that 26 of these ORFs code for unique proteins that have no reliable identity when compared to database entries. Based on phylogenetic analysis, MED16 represents a new genus with siphovirus morphology. In total, 35 MED16 ORFs were given a putative functional annotation, including those coding for the proteins responsible for virion morphogenesis, phage-host interactions, and DNA metabolism. In addition, a gene encoding a preQ0 DNA deoxyribosyltransferase (DpdA) is present in the genome of MED16 and the LC-MS/MS analysis indicates 2'-deoxy-7-amido-7-deazaguanosine (dADG)-modified phage DNA, which, to our knowledge, has never been experimentally validated in genomes of Pantoea phages. Thus, the data presented in this study provide new information on Pantoea-infecting viruses and offer novel insights into the diversity of DNA modifications in bacteriophages.


Assuntos
DNA Viral , Genoma Viral , Guanosina , Fases de Leitura Aberta , Pantoea/virologia , Siphoviridae , Proteínas Virais , DNA Viral/genética , DNA Viral/metabolismo , Guanosina/análogos & derivados , Guanosina/química , Guanosina/metabolismo , Siphoviridae/genética , Siphoviridae/metabolismo , Proteínas Virais/genética , Proteínas Virais/metabolismo
12.
J Cell Biol ; 220(7)2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-33999101

RESUMO

Rab40b is a SOCS box-containing protein that regulates the secretion of MMPs to facilitate extracellular matrix remodeling during cell migration. Here, we show that Rab40b interacts with Cullin5 via the Rab40b SOCS domain. We demonstrate that loss of Rab40b-Cullin5 binding decreases cell motility and invasive potential and show that defective cell migration and invasion stem from alteration to the actin cytoskeleton, leading to decreased invadopodia formation, decreased actin dynamics at the leading edge, and an increase in stress fibers. We also show that these stress fibers anchor at less dynamic, more stable focal adhesions. Mechanistically, changes in the cytoskeleton and focal adhesion dynamics are mediated in part by EPLIN, which we demonstrate to be a binding partner of Rab40b and a target for Rab40b-Cullin5-dependent localized ubiquitylation and degradation. Thus, we propose a model where Rab40b-Cullin5-dependent ubiquitylation regulates EPLIN localization to promote cell migration and invasion by altering focal adhesion and cytoskeletal dynamics.


Assuntos
Citoesqueleto de Actina/genética , Actinas/genética , Proteínas do Citoesqueleto/genética , Movimento Celular/genética , Matriz Extracelular/genética , Adesões Focais/genética , Humanos , Fibras de Estresse/genética
13.
Microorganisms ; 9(3)2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33807116

RESUMO

A cold-adapted siphovirus, vB_PagS_AAS23 (AAS23) was isolated in Lithuania using the Pantoea agglomerans strain AUR for the phage propagation. The double-stranded DNA genome of AAS23 (51,170 bp) contains 92 probable protein encoding genes, and no genes for tRNA. A comparative sequence analysis revealed that 25 of all AAS23 open reading frames (ORFs) code for unique proteins that have no reliable identity to database entries. Based on the phylogenetic analysis, AAS23 has no close relationship to other viruses publicly available to date and represents a single species of the genus Sauletekiovirus within the family Drexlerviridae. The phage is able to form plaques in bacterial lawns even at 4 °C and demonstrates a depolymerase activity. Thus, the data presented in this study not only provides the information on Pantoea-infecting bacteriophages, but also offers novel insights into the diversity of cold-adapted viruses and their potential to be used as biocontrol agents.

14.
Anticancer Res ; 41(3): 1401-1406, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33788731

RESUMO

BACKGROUND/AIM: Pancreatic ductal adenocarcinoma is one of the deadliest forms of human cancer. Since only a vast panel of cell lines can fully recapitulate disease heterogeneity, our aim was to establish a new pancreatic cancer cell line. MATERIALS AND METHODS: Newly established pancreatic ductal adenocarcinoma cell line Capan-26 was characterized by assessing growth rate, tumor and stem cell marker expression, colony forming efficiency, mutations of KRAS and TP53 genes, karyotype and sensitivity to drug treatment. RESULTS: Cell doubling time was 74 h. We detected CA19-9, CEACAM6, CD44, OCT4 and ZEB1 expression in Capan-26 cell line. Cells formed colonies in soft agar, have a deletion of KRAS exon 3 and a point mutation V172F in TP53 exon 5. They are a mixed aneuploid/polyploid population with high sensitivity to gemcitabine. CONCLUSION: Capan-26 is a unique cell line that may be used to study the mechanism of pancreatic cancer.


Assuntos
Carcinoma Ductal Pancreático/patologia , Neoplasias Pancreáticas/patologia , Idoso , Antígenos CD/genética , Antígenos CD/metabolismo , Antimetabólitos Antineoplásicos/farmacologia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Feminino , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Cariotipagem , Mutação , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteína Supressora de Tumor p53/genética , Gencitabina
15.
Viruses ; 13(3)2021 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-33673419

RESUMO

Achromobacter spp. are ubiquitous in nature and are increasingly being recognized as emerging nosocomial pathogens. Nevertheless, to date, only 30 complete genome sequences of Achromobacter phages are available in GenBank, and nearly all of those phages were isolated on Achromobacter xylosoxidans. Here, we report the isolation and characterization of bacteriophage vB_AchrS_AchV4. To the best of our knowledge, vB_AchrS_AchV4 is the first virus isolated from Achromobacter spanius. Both vB_AchrS_AchV4 and its host, Achromobacter spanius RL_4, were isolated in Lithuania. VB_AchrS_AchV4 is a siphovirus, since it has an isometric head (64 ± 3.2 nm in diameter) and a non-contractile flexible tail (232 ± 5.4). The genome of vB_AchrS_AchV4 is a linear dsDNA molecule of 59,489 bp with a G+C content of 62.8%. It contains no tRNA genes, yet it includes 82 protein-coding genes, of which 27 have no homologues in phages. Using bioinformatics approaches, 36 vB_AchrS_AchV4 genes were given a putative function. A further four were annotated based on the results of LC-MS/MS. Comparative analyses revealed that vB_AchrS_AchV4 is a singleton siphovirus with no close relatives among known tailed phages. In summary, this work not only describes a novel and unique phage, but also advances our knowledge of genetic diversity and evolution of Achromobacter bacteriophages.


Assuntos
Achromobacter/genética , Bacteriófagos/genética , Composição de Bases/genética , Biologia Computacional/métodos , DNA/genética , Vírus de DNA/genética , DNA Viral/genética , Genoma Viral/genética , Filogenia , RNA de Transferência/genética , Análise de Sequência de DNA/métodos
16.
Viruses ; 12(4)2020 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-32340233

RESUMO

A novel cold-adapted siphovirus, vB_PagS_AAS21 (AAS21), was isolated in Lithuania using Pantoea agglomerans as the host for phage propagation. AAS21 has an isometric head (~85 nm in diameter) and a non-contractile flexible tail (~174 × 10 nm). With a genome size of 116,649 bp, bacteriophage AAS21 is the largest Pantoea-infecting siphovirus sequenced to date. The genome of AAS21 has a G+C content of 39.0% and contains 213 putative protein-encoding genes and 29 genes for tRNAs. A comparative sequence analysis revealed that 89 AAS21 open reading frames (ORFs) code for unique proteins that have no reliable identity to database entries. In total, 63 AAS21 ORFs were functionally annotated, including those coding for the proteins responsible for virion morphogenesis, phage-host interactions, and DNA metabolism. Proteomic analysis led to the experimental identification of 19 virion proteins, including 11 that were predicted by bioinformatics approaches. Based on comparative phylogenetic analysis, AAS21 cannot be assigned to any genus currently recognized by ICTV and may represents a new branch of viruses within the family Siphoviridae.


Assuntos
Bacteriófagos/classificação , Bacteriófagos/fisiologia , Pantoea/virologia , Adaptação Biológica , Bacteriófagos/ultraestrutura , Temperatura Baixa , Genoma Viral , Genômica/métodos , Fases de Leitura Aberta , Filogenia , Siphoviridae
17.
J Cell Sci ; 133(9)2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-32184265

RESUMO

During mitotic cell division, the actomyosin cytoskeleton undergoes several dynamic changes that play key roles in progression through mitosis. Although the regulators of cytokinetic ring formation and contraction are well established, proteins that regulate cortical stability during anaphase and telophase have been understudied. Here, we describe a role for CLIC4 in regulating actin and actin regulators at the cortex and cytokinetic cleavage furrow during cytokinesis. We first describe CLIC4 as a new component of the cytokinetic cleavage furrow that is required for successful completion of mitotic cell division. We also demonstrate that CLIC4 regulates the remodeling of the sub-plasma-membrane actomyosin network within the furrow by recruiting MST4 kinase (also known as STK26) and regulating ezrin phosphorylation. This work identifies and characterizes new molecular players involved in regulating cortex stiffness and blebbing during the late stages of cytokinetic furrowing.


Assuntos
Citocinese , Citoesqueleto , Citoesqueleto de Actina , Actinas , Microtúbulos
18.
Sci Rep ; 10(1): 788, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31964920

RESUMO

Human activating signal cointegrator homology (ASCH) domain-containing proteins are widespread and diverse but, at present, the vast majority of those proteins have no function assigned to them. This study demonstrates that the 103-amino acid Escherichia coli protein YqfB, previously identified as hypothetical, is a unique ASCH domain-containing amidohydrolase responsible for the catabolism of N4-acetylcytidine (ac4C). YqfB has several interesting and unique features: i) it is the smallest monomeric amidohydrolase described to date, ii) it is active towards structurally different N4-acylated cytosines/cytidines, and iii) it has a high specificity for these substrates (kcat/Km up to 2.8 × 106 M-1 s-1). Moreover, our results suggest that YqfB contains a unique Thr-Lys-Glu catalytic triad, and Arg acting as an oxyanion hole. The mutant lacking the yqfB gene retains the ability to grow, albeit poorly, on N4-acetylcytosine as a source of uracil, suggesting that an alternative route for the utilization of this compound exists in E. coli. Overall, YqfB ability to hydrolyse various N4-acylated cytosines and cytidines not only sheds light on the long-standing mystery of how ac4C is catabolized in bacteria, but also expands our knowledge of the structural diversity within the active sites of amidohydrolases.


Assuntos
Amidoidrolases/genética , Amidoidrolases/metabolismo , Citosina/metabolismo , Escherichia coli/enzimologia , Acilação , Amidoidrolases/química , Domínio Catalítico , Cristalografia por Raios X , Citosina/química , Escherichia coli/genética , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Modelos Moleculares , Mutagênese Sítio-Dirigida , Conformação Proteica , Domínios Proteicos , Especificidade por Substrato
19.
J Clin Med ; 8(12)2019 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-31810268

RESUMO

Although treatment of colorectal cancer with 5-florouracil and oxaliplatin is widely used, it is frequently followed by a relapse. Therefore, there is an urgent need for profound understanding of chemotherapy resistance mechanisms as well as the profiling of predictive markers for individualized treatment. In this study, we identified the changes in 14 miRNAs in 5-fluouracil and 40 miRNAs in oxaliplatin-resistant cell lines by miRNA sequencing. The decrease in miR-224-5p expression in the 5-fluorouracil-resistant cells correlated with drug insensitivity due to its overexpression-induced drug-dependent apoptosis. On the other hand, the miR-23b/27b/24-1 cluster was overexpressed in oxaliplatin-resistant cells. The knockout of miR-23b led to the partial restoration of oxaliplatin susceptibility, showing the essential role of miR-23b in the development of drug resistance by this cluster. Proteomic analysis identified target genes of miR-23b and showed that endothelial-mesenchymal transition (EMT) was implicated in oxaliplatin insensibility. Data revealed that EMT markers, such as vimentin and SNAI2, were expressed moderately higher in the oxaliplatin-resistant cells and their expression increased further in the less drug-resistant cells, which had miR-23b knockout. This establishes that the balance of EMT contributes to the drug resistance, showing the importance of the miR-23b-mediated fine-tuning of EMT in oxaliplatin-resistant cancer cells.

20.
Materials (Basel) ; 12(23)2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31783647

RESUMO

Hybrid organometallic polymers are a class of functional materials which can be used to produce structures with sub-micron features via laser two-photon polymerisation. Previous studies demonstrated the relative biocompatibility of Al and Zr containing hybrid organometallic polymers in vitro. However, a deeper understanding of their effects on intracellular processes is needed if a tissue engineering strategy based on these materials is to be envisioned. Herein, primary rat myogenic cells were cultured on spin-coated Al and Zr containing polymer surfaces to investigate how each material affects the viability, adhesion strength, adhesion-associated protein expression, rate of cellular metabolism and collagen secretion. We found that the investigated surfaces supported cellular growth to full confluency. A subsequent MTT assay showed that glass and Zr surfaces led to higher rates of metabolism than did the Al surfaces. A viability assay revealed that all surfaces supported comparable levels of cell viability. Cellular adhesion strength assessment showed an insignificantly stronger relative adhesion after 4 h of culture than after 24 h. The largest amount of collagen was secreted by cells grown on the Al-containing surface. In conclusion, the materials were found to be biocompatible in vitro and have potential for bioengineering applications.

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