Role of small GTPases in Trypanosoma cruzi invasion in MDCK cell lines

2005 ◽  
Vol 96 (3) ◽  
pp. 171-177 ◽  
Author(s):  
Dutra JMF ◽  
Bonilha VL ◽  
De Souza W ◽  
Carvalho TMU
Keyword(s):  
Trypanosoma Cruzi ◽  
Cell Lines ◽  
Mdck Cell ◽  
Small Gtpases

scholarly journals Dual Role for Transforming Growth Factor β-Dependent Signaling in Trypanosoma cruzi Infection of Mammalian Cells

2000 ◽  
Vol 68 (4) ◽  
pp. 2077-2081 ◽  
Author(s):  
Belinda S. Hall ◽  
Miercio A. Pereira
Keyword(s):  
Gene Expression ◽  
Growth Factor ◽  
Trypanosoma Cruzi ◽  
Host Cell ◽  
Cell Lines ◽  
Mammalian Cells ◽  
Transforming Growth Factor ◽  
Growth Arrest ◽  
Transforming Growth Factor Β

ABSTRACT Expression of functional transforming growth factor β (TGF-β) receptors (TβR) is required for the invasion of mammalian cells by the protozoan parasite Trypanosoma cruzi. However, the precise role of this host cell signaling complex in T. cruzi infection is unknown. To investigate the role of the TGF-β signaling pathway, infection levels were studied in the mink lung epithelial cell lines JD1, JM2, and JM3. These cells express inducible mutant TβR1 proteins that cannot induce growth arrest in response to TGF-β but still transmit the signal for TGF-β-dependent gene expression. In the absence of mutant receptor expression, trypomastigotes invaded the cells at a low level. Induction of the mutant receptors caused an increase in infection in all three cell lines, showing that the requirement for TGF-β signaling at invasion can be divorced from TGF-β-induced growth arrest. TGF-β pretreatment of mink lung cells expressing wild-type TβR1 caused a marked enhancement of infection, but no enhancement was seen in JD1, JM2, and JM3 cells, showing that the ability of TGF-β to stimulate infection is associated with growth arrest. Likewise, expression of SMAD7 or SMAD2SA, inhibitors of TGF-β signaling, did not block infection by T. cruzi but did block the enhancement of infection by TGF-β. Taken together, these results show that there is a dual role for TGF-β signaling in T. cruzi infection. The initial invasion of the host cell is independent of both TGF-β-dependent gene expression and growth arrest, but TGF-β stimulation of infection requires a fully functional TGF-β signaling pathway.

scholarly journals MICU1 and MICU2 Play an Essential Role in Mitochondrial Ca2+ Uptake, Growth, and Infectivity of the Human Pathogen Trypanosoma cruzi

mBio ◽  
2019 ◽  
Vol 10 (3) ◽  
Author(s):  
Mayara S. Bertolini ◽  
Miguel A. Chiurillo ◽  
Noelia Lander ◽  
Anibal E. Vercesi ◽  
Roberto Docampo
Keyword(s):  
Trypanosoma Cruzi ◽  
Cell Lines ◽  
Citrate Synthase ◽  
Host Cells ◽  
Mitochondrial Calcium ◽  
Content Type ◽  
Mitochondrial Calcium Uniporter ◽  
Calcium Uniporter ◽  
Eukaryotic Supergroup

ABSTRACT The mitochondrial Ca2+ uptake in trypanosomatids, which belong to the eukaryotic supergroup Excavata, shares biochemical characteristics with that of animals, which, together with fungi, belong to the supergroup Opisthokonta. However, the composition of the mitochondrial calcium uniporter (MCU) complex in trypanosomatids is quite peculiar, suggesting lineage-specific adaptations. In this work, we used Trypanosoma cruzi to study the role of orthologs for mitochondrial calcium uptake 1 (MICU1) and MICU2 in mitochondrial Ca2+ uptake. T. cruzi MICU1 (TcMICU1) and TcMICU2 have mitochondrial targeting signals, two canonical EF-hand calcium-binding domains, and localize to the mitochondria. Using the CRISPR/Cas9 system (i.e., clustered regularly interspaced short palindromic repeats with Cas9), we generated TcMICU1 and TcMICU2 knockout (-KO) cell lines. Ablation of either TcMICU1 or TcMICU2 showed a significantly reduced mitochondrial Ca2+ uptake in permeabilized epimastigotes without dissipation of the mitochondrial membrane potential or effects on the AMP/ATP ratio or citrate synthase activity. However, none of these proteins had a gatekeeper function at low cytosolic Ca2+ concentrations ([Ca2+]cyt), as occurs with their mammalian orthologs. TcMICU1-KO and TcMICU2-KO epimastigotes had a lower growth rate and impaired oxidative metabolism, while infective trypomastigotes have a reduced capacity to invade host cells and to replicate within them as amastigotes. The findings of this work, which is the first to study the role of MICU1 and MICU2 in organisms evolutionarily distant from animals, suggest that, although these components were probably present in the last eukaryotic common ancestor (LECA), they developed different roles during evolution of different eukaryotic supergroups. The work also provides new insights into the adaptations of trypanosomatids to their particular life styles. IMPORTANCE Trypanosoma cruzi is the etiologic agent of Chagas disease and belongs to the early-branching eukaryotic supergroup Excavata. Its mitochondrial calcium uniporter (MCU) subunit shares similarity with the animal ortholog that was important to discover its encoding gene. In animal cells, the MICU1 and MICU2 proteins act as Ca2+ sensors and gatekeepers of the MCU, preventing Ca2+ uptake under resting conditions and favoring it at high cytosolic Ca2+ concentrations ([Ca2+]cyt). Using the CRISPR/Cas9 technique, we generated TcMICU1 and TcMICU2 knockout cell lines and showed that MICU1 and -2 do not act as gatekeepers at low [Ca2+]cyt but are essential for normal growth, host cell invasion, and intracellular replication, revealing lineage-specific adaptations.

scholarly journals Shared and specific functions of Arfs 1–5 at the Golgi revealed by systematic knockouts

2021 ◽  
Author(s):  
Mirjam Pennauer ◽  
Katarzyna Buczak ◽  
Cristina Prescianotto-Baschong ◽  
Martin Spiess
Keyword(s):  
Cell Lines ◽  
Secretory Pathway ◽  
Small Gtpases ◽  
Class I ◽  
Growth Defect ◽  
Human Class ◽  
Slight Growth ◽  
Dependent Processes

AbstractThe ADP-ribosylation factors (Arfs) are small GTPases regulating membrane traffic in the secretory pathway. They are closely related and appear to have overlapping functions, regulators, and effectors. The functional specificity of individual Arfs and the extent of redundancy in vivo are still largely unknown. We addressed these questions by CRISPR/Cas9-mediated genomic deletion of the human class I (Arfs 1 and 3) and class II (Arfs 4 and 5) Arfs, either individually or in combination. Cells lacking individual Arfs or certain combinations were viable with only a slight growth defect when lacking Arf1 or Arf4. However, Arf1 and 4, and Arf4 and 5 could not be deleted simultaneously. Hence, class I Arfs are not essential and Arf4 alone was found to be sufficient for cell viability. Remarkably, two single knockouts produced specific and distinct phenotypes. Upon deletion of Arf1, the Golgi complex was enlarged and recruitment of vesicle coats decreased, confirming a major role of Arf1 in coat formation at the Golgi. Cell lines deleted for Arf4 exhibited secretion of ER resident proteins, indicating a specific defect in coatomer-dependent ER protein retrieval by the KDEL receptors. The knockout cell lines will be a useful tool to study other Arf-dependent processes.

scholarly journals Shared and specific functions of Arfs 1–5 at the Golgi revealed by systematic knockouts

2021 ◽  
Vol 221 (1) ◽  
Author(s):  
Mirjam Pennauer ◽  
Katarzyna Buczak ◽  
Cristina Prescianotto-Baschong ◽  
Martin Spiess
Keyword(s):  
Cell Lines ◽  
Secretory Pathway ◽  
Small Gtpases ◽  
Class I ◽  
Human Class ◽  
Functional Specificity ◽  
Growth Defects ◽  
Slight Growth ◽  
Dependent Processes

ADP-ribosylation factors (Arfs) are small GTPases regulating membrane traffic in the secretory pathway. They are closely related and appear to have overlapping functions, regulators, and effectors. The functional specificity of individual Arfs and the extent of redundancy are still largely unknown. We addressed these questions by CRISPR/Cas9-mediated genomic deletion of the human class I (Arf1/3) and class II (Arf4/5) Arfs, either individually or in combination. Most knockout cell lines were viable with slight growth defects only when lacking Arf1 or Arf4. However, Arf1+4 and Arf4+5 could not be deleted simultaneously. Class I Arfs are nonessential, and Arf4 alone is sufficient for viability. Upon Arf1 deletion, the Golgi was enlarged, and recruitment of vesicle coats decreased, confirming a major role of Arf1 in vesicle formation at the Golgi. Knockout of Arf4 caused secretion of ER-resident proteins, indicating specific defects in coatomer-dependent ER protein retrieval by KDEL receptors. The knockout cell lines will be useful tools to study other Arf-dependent processes.

Glioblastoma invasion and NMDA receptors: A novel prospect

2019 ◽  
Vol 106 (3) ◽  
pp. 250-260 ◽  
Author(s):  
DN Nandakumar ◽  
P Ramaswamy ◽  
C Prasad ◽  
D Srinivas ◽  
K Goswami
Keyword(s):  
Glutamate Receptors ◽  
Cell Lines ◽  
Intracellular Signaling ◽  
Transcript Level ◽  
Glioblastoma Cells ◽  
Invasion And Migration ◽  
Matrigel Invasion ◽  
Nmdar Activation ◽  
And Migration

Purpose Glioblastoma cells create glutamate-rich tumor microenvironment, which initiates activation of ion channels and modulates downstream intracellular signaling. N-methyl-D-aspartate receptors (NMDARs; a type of glutamate receptors) have a high affinity for glutamate. The role of NMDAR activation on invasion of glioblastoma cells and the crosstalk with α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) is yet to be explored. Main methods LN18, U251MG, and patient-derived glioblastoma cells were stimulated with NMDA to activate NMDAR glutamate receptors. The role of NMDAR activation on invasion and migration and its crosstalk with AMPAR were evaluated. Invasion and migration of glioblastoma cells were investigated by in vitro trans-well Matrigel invasion and trans-well migration assays, respectively. Expression of NMDARs and AMPARs at transcript level was evaluated by quantitative real-time polymerase chain reaction. Results We determined that NMDA stimulation leads to enhanced invasion in LN18, U251MG, and patient-derived glioblastoma cells, whereas inhibition of NMDAR using MK-801, a non-competitive antagonist of the NMDAR, significantly decreased the invasive capacity. Concordant with these findings, migration was significantly augmented by NMDAR in both cell lines. Furthermore, NMDA stimulation upregulated the expression of GluN2 and GluA1 subunits at the transcript level. Conclusions This study demonstrated the previously unexplored role of NMDAR in invasion of glioblastoma cells. Furthermore, the expression of the GluN2 subunit of NMDAR and the differential overexpression of the GluA1 subunit of AMPAR in both cell lines provide a plausible rationale of crosstalk between these calcium-permeable subunits in the glutamate-rich microenvironment of glioblastoma.

scholarly journals Hsa_circ_0005273 facilitates breast cancer tumorigenesis by regulating YAP1-hippo signaling pathway

2021 ◽  
Vol 40 (1) ◽  
Author(s):  
Xuehui Wang ◽  
Changle Ji ◽  
Jiashu Hu ◽  
Xiaochong Deng ◽  
Wenfang Zheng ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Signaling Pathway ◽  
Cell Lines ◽  
Luciferase Reporter ◽  
Circular Rnas ◽  
Hippo Signaling ◽  
Hippo Signaling Pathway ◽  
Potential Biomarker

Abstract Background Circular RNAs (circRNAs), a novel class of endogenous RNAs, have shown to participate in the development of breast cancer (BC). Hsa_circ_0005273 is a circRNA generated from several exons of PTK2. However, the potential functional role of hsa_circ_0005273 in BC remains largely unknown. Here we aim to evaluate the role of hsa_circ_0005273 in BC. Methods The expression level of hsa_circ_0005273 and miR-200a-3p were examined by RT-qPCR in BC tissues and cell lines. The effect of knocking down hsa_circ_0005273 in BC cell lines were evaluated by examinations of cell proliferation, migration and cell cycle. In addition, xenografts experiment in nude mice were performed to evaluate the effect of hsa_circ_0005273 in BC. RNA immunoprecipitation assay, RNA probe pull-down assay, luciferase reporter assay and fluorescence in situ hybridization were conducted to confirm the relationship between hsa_circ_0005273, miR-200a-3p and YAP1. Results Hsa_circ_0005273 is over-expressed in BC tissues and cell lines, whereas miR-200a-3p expression is repressed. Depletion of hsa_circ_0005273 inhibited the progression of BC cells in vitro and in vivo, while overexpression of hsa_circ_0005273 exhibited the opposite effect. Importantly, hsa_circ_0005273 upregulated YAP1 expression and inactivated Hippo pathway via sponging miR-200a-3p to promote BC progression. Conclusions Hsa_circ_0005273 regulates the miR-200a-3p/YAP1 axis and inactivates Hippo signaling pathway to promote BC progression, which may become a potential biomarker and therapeutic target.

scholarly journals The inhibitory role of synthesized Nickel oxide nanoparticles against Hep-G2, MCF-7, and HT-29 cell lines: the inhibitory role of NiO NPs against Hep-G2, MCF-7, and HT-29 cell lines

2021 ◽  
Vol 14 (3) ◽  
pp. 443-453
Author(s):  
Mohammad Amin Jadidi Kouhbanani ◽  
Yasin Sadeghipour ◽  
Mina Sarani ◽  
Erfan Sefidgar ◽  
Saba Ilkhani ◽  
...  
Keyword(s):  
Nickel Oxide ◽  
Cell Lines ◽  
Oxide Nanoparticles ◽  
Hep G2 ◽  
Nickel Oxide Nanoparticles ◽  
Inhibitory Role ◽  
Nio Nps ◽  
Ht 29 ◽  
Mcf 7

scholarly journals Epigenomic Analysis of RAD51 ChIP-seq Data Reveals cis-regulatory Elements Associated with Autophagy in Cancer Cell Lines

Cancers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 2547
Author(s):  
Keunsoo Kang ◽  
Yoonjung Choi ◽  
Hyeonjin Moon ◽  
Chaelin You ◽  
Minjin Seo ◽  
...  
Keyword(s):  
Gene Regulation ◽  
Homologous Recombination ◽  
Cell Lines ◽  
Regulatory Elements ◽  
Binding Motif ◽  
Genome Wide ◽  
E Box ◽  
Autophagy Pathway ◽  
Mcf 7

RAD51 is a recombinase that plays a pivotal role in homologous recombination. Although the role of RAD51 in homologous recombination has been extensively studied, it is unclear whether RAD51 can be involved in gene regulation as a co-factor. In this study, we found evidence that RAD51 may contribute to the regulation of genes involved in the autophagy pathway with E-box proteins such as USF1, USF2, and/or MITF in GM12878, HepG2, K562, and MCF-7 cell lines. The canonical USF binding motif (CACGTG) was significantly identified at RAD51-bound cis-regulatory elements in all four cell lines. In addition, genome-wide USF1, USF2, and/or MITF-binding regions significantly coincided with the RAD51-associated cis-regulatory elements in the same cell line. Interestingly, the promoters of genes associated with the autophagy pathway, such as ATG3 and ATG5, were significantly occupied by RAD51 and regulated by RAD51 in HepG2 and MCF-7 cell lines. Taken together, these results unveiled a novel role of RAD51 and provided evidence that RAD51-associated cis-regulatory elements could possibly be involved in regulating autophagy-related genes with E-box binding proteins.

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