scholarly journals A comprehensive genetic characterisation of the mitochondrial Ca2+ uniporter in Drosophila

2018 ◽  
Author(s):  
Roberta Tufi ◽  
Thomas P. Gleeson ◽  
Sophia von Stockum ◽  
Victoria L. Hewitt ◽  
Juliette J. Lee ◽  
...  
Keyword(s):  
Cell Death ◽  
Genetic Analysis ◽  
Genetic Interaction ◽  
Model Organisms ◽  
Severe Phenotype ◽  
Genetic Characterisation ◽  
Important Mediator ◽  
Interaction Studies ◽  
Independent Functions ◽  
Shed Light

AbstractMitochondrial Ca2+ uptake is an important mediator of metabolism and cell death. Identification of components of the highly conserved mitochondrial Ca2+ uniporter has opened it up to genetic analysis in model organisms. Here we report a comprehensive genetic characterisation of the known uniporter components conserved in Drosophila. While loss of MCU or EMRE abolishes fast mitochondrial Ca2+ uptake, this results in surprisingly mild phenotypes. In contrast, loss of the regulatory gatekeeper component MICU1 has a much more severe phenotype, being developmental lethal, consistent with unregulated Ca2+ uptake. Mutants for MICU3 are viable with mild neurological phenotypes. Genetic interaction studies reveal that MICU1 and MICU3 are not functionally interchangeable. More surprisingly, loss of MCU or EMRE does not suppress MICU1 mutant lethality, suggesting that the lethality results from MCU-independent functions. This study helps shed light on the physiological requirements of the mitochondrial Ca2+ uniporter, and provides a suite of tools to interrogate their interplay in homeostasis and disease conditions.

scholarly journals How the Other Half Lives: What p53 Does When It Is Not Being a Transcription Factor

2019 ◽  
Vol 21 (1) ◽  
pp. 13 ◽  
Author(s):  
Teresa Ho ◽  
Ban Xiong Tan ◽  
David Lane
Keyword(s):  
Cell Death ◽  
Transcription Factor ◽  
Genomic Instability ◽  
Cellular Response ◽  
Molecular Mechanisms ◽  
Human Cancer ◽  
Context Dependency ◽  
The Other ◽  
Independent Functions ◽  
Shed Light

It has been four decades since the discovery of p53, the designated ‘Guardian of the Genome’. P53 is primarily known as a master transcription factor and critical tumor suppressor, with countless studies detailing the mechanisms by which it regulates a host of gene targets and their consequent signaling pathways. However, transcription-independent functions of p53 also strongly define its tumor-suppressive capabilities and recent findings shed light on the molecular mechanisms hinted at by earlier efforts. This review highlights the transcription-independent mechanisms by which p53 influences the cellular response to genomic instability (in the form of replication stress, centrosome homeostasis, and transposition) and cell death. We also pinpoint areas for further investigation in order to better understand the context dependency of p53 transcription-independent functions and how these are perturbed when TP53 is mutated in human cancer.

scholarly journals The STING1 network regulates autophagy and cell death

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Ruoxi Zhang ◽  
Rui Kang ◽  
Daolin Tang
Keyword(s):  
Cell Death ◽  
Mitotic Cell ◽  
Therapeutic Interventions ◽  
Type I Interferons ◽  
Microbial Pathogens ◽  
Type I ◽  
Autophagic Degradation ◽  
Health And Disease ◽  
Shed Light ◽  
Pro Inflammatory Cytokines

AbstractCell death and immune response are at the core of life. In past decades, the endoplasmic reticulum (ER) protein STING1 (also known as STING or TMEM173) was found to play a fundamental role in the production of type I interferons (IFNs) and pro-inflammatory cytokines in response to DNA derived from invading microbial pathogens or damaged hosts by activating multiple transcription factors. In addition to this well-known function in infection, inflammation, and immunity, emerging evidence suggests that the STING1-dependent signaling network is implicated in health and disease by regulating autophagic degradation or various cell death modalities (e.g., apoptosis, necroptosis, pyroptosis, ferroptosis, mitotic cell death, and immunogenic cell death [ICD]). Here, we outline the latest advances in our understanding of the regulating mechanisms and signaling pathways of STING1 in autophagy and cell death, which may shed light on new targets for therapeutic interventions.

scholarly journals Role of Hypoxia-Mediated Autophagy in Tumor Cell Death and Survival

Cancers ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 533
Author(s):  
Rania F. Zaarour ◽  
Bilal Azakir ◽  
Edries Y. Hajam ◽  
Husam Nawafleh ◽  
Nagwa A. Zeinelabdin ◽  
...  
Keyword(s):  
Cell Death ◽  
Type I ◽  
Dependent Manner ◽  
Destruction Process ◽  
Tumor Cell Death ◽  
Complex Regulation ◽  
Cancer Immunotherapies ◽  
The Relationship ◽  
Shed Light

Programmed cell death or type I apoptosis has been extensively studied and its contribution to the pathogenesis of disease is well established. However, autophagy functions together with apoptosis to determine the overall fate of the cell. The cross talk between this active self-destruction process and apoptosis is quite complex and contradictory as well, but it is unquestionably decisive for cell survival or cell death. Autophagy can promote tumor suppression but also tumor growth by inducing cancer-cell development and proliferation. In this review, we will discuss how autophagy reprograms tumor cells in the context of tumor hypoxic stress. We will illustrate how autophagy acts as both a suppressor and a driver of tumorigenesis through tuning survival in a context dependent manner. We also shed light on the relationship between autophagy and immune response in this complex regulation. A better understanding of the autophagy mechanisms and pathways will undoubtedly ameliorate the design of therapeutics aimed at targeting autophagy for future cancer immunotherapies.

Genetic analysis of myosin II assembly and organization in model organisms

2005 ◽  
Vol 62 (19-20) ◽  
pp. 2270-2282 ◽  
Author(s):  
M. L. Landsverk ◽  
H. F. Epstein
Keyword(s):  
Genetic Analysis ◽  
Myosin Ii ◽  
Model Organisms

scholarly journals Regulation of mitochondria-dynactin interaction and mitochondrial retrograde transport in axons

eLife ◽  
2017 ◽  
Vol 6 ◽  
Author(s):  
Catherine M Drerup ◽  
Amy L Herbert ◽  
Kelly R Monk ◽  
Alex V Nechiporuk
Keyword(s):  
Neural Circuit ◽  
Genetic Interaction ◽  
Retrograde Transport ◽  
Genetic Screen ◽  
Binding Domain ◽  
Loss Of Function ◽  
Mitochondrial Transport ◽  
Interaction Studies ◽  
Mitochondrial Motility ◽  
And Function

Mitochondrial transport in axons is critical for neural circuit health and function. While several proteins have been found that modulate bidirectional mitochondrial motility, factors that regulate unidirectional mitochondrial transport have been harder to identify. In a genetic screen, we found a zebrafish strain in which mitochondria fail to attach to the dynein retrograde motor. This strain carries a loss-of-function mutation in actr10, a member of the dynein-associated complex dynactin. The abnormal axon morphology and mitochondrial retrograde transport defects observed in actr10 mutants are distinct from dynein and dynactin mutant axonal phenotypes. In addition, Actr10 lacking the dynactin binding domain maintains its ability to bind mitochondria, arguing for a role for Actr10 in dynactin-mitochondria interaction. Finally, genetic interaction studies implicated Drp1 as a partner in Actr10-dependent mitochondrial retrograde transport. Together, this work identifies Actr10 as a factor necessary for dynactin-mitochondria interaction, enhancing our understanding of how mitochondria properly localize in axons.

New imidoyl-indazole platinum (II) complexes as potential anticancer agents: Synthesis, evaluation of cytotoxicity, cell death and experimental-theoretical DNA interaction studies

2017 ◽  
Vol 174 ◽  
pp. 90-101 ◽  
Author(s):  
Alan R. Cabrera ◽  
Christian Espinosa-Bustos ◽  
Mario Faúndez ◽  
Jaime Meléndez ◽  
Pablo Jaque ◽  
...  
Keyword(s):  
Cell Death ◽  
Anticancer Agents ◽  
Dna Interaction ◽  
Interaction Studies

scholarly journals ATG8 Is Essential Specifically for an Autophagy-Independent Function in Apicoplast Biogenesis in Blood-Stage Malaria Parasites

mBio ◽  
2018 ◽  
Vol 9 (1) ◽  
Author(s):  
Marta Walczak ◽  
Suresh M. Ganesan ◽  
Jacquin C. Niles ◽  
Ellen Yeh
Keyword(s):  
Protein Import ◽  
Blood Stage ◽  
Model Organisms ◽  
Secondary Endosymbiosis ◽  
Organelle Biogenesis ◽  
Independent Function ◽  
Malaria Parasites ◽  
Apicomplexan Parasites ◽  
Independent Functions ◽  
Parasite Replication

ABSTRACT Plasmodium parasites and related pathogens contain an essential nonphotosynthetic plastid organelle, the apicoplast, derived from secondary endosymbiosis. Intriguingly, a highly conserved eukaryotic protein, autophagy-related protein 8 (ATG8), has an autophagy-independent function in the apicoplast. Little is known about the novel apicoplast function of ATG8 and its importance in blood-stage Plasmodium falciparum. Using a P. falciparum strain in which ATG8 expression was conditionally regulated, we showed that P. falciparum ATG8 (PfATG8) is essential for parasite replication. Significantly, growth inhibition caused by the loss of PfATG8 was reversed by addition of isopentenyl pyrophosphate (IPP), which was previously shown to rescue apicoplast defects in P. falciparum. Parasites deficient in PfATG8, but whose growth was rescued by IPP, had lost their apicoplast. We designed a suite of functional assays, including a new fluorescence in situ hybridization (FISH) method for detection of the low-copy-number apicoplast genome, to interrogate specific steps in apicoplast biogenesis and detect apicoplast defects which preceded the block in parasite replication. Though protein import and membrane expansion of the apicoplast were unaffected, the apicoplast was not inherited by daughter parasites. Our findings demonstrate that, though multiple autophagy-dependent and independent functions have been proposed for PfATG8, only its role in apicoplast biogenesis is essential in blood-stage parasites. We propose that PfATG8 is required for fission or segregation of the apicoplast during parasite replication. IMPORTANCE Plasmodium parasites, which cause malaria, and related apicomplexan parasites are important human and veterinary pathogens. They are evolutionarily distant from traditional model organisms and possess a unique plastid organelle, the apicoplast, acquired by an unusual eukaryote-eukaryote endosymbiosis which established novel protein/lipid import and organelle inheritance pathways in the parasite cell. Though the apicoplast is essential for parasite survival in all stages of its life cycle, little is known about these novel biogenesis pathways. We show that malaria parasites have adapted a highly conserved protein required for macroautophagy in yeast and mammals to function specifically in apicoplast inheritance. Our finding elucidates a novel mechanism of organelle biogenesis, essential for pathogenesis, in this divergent branch of pathogenic eukaryotes.

Fungal genetics

2017 ◽  
Author(s):  
Paul S. Dyer ◽  
Carol A Munro ◽  
Rosie E. Bradshaw
Keyword(s):  
Genetic Analysis ◽  
Cellular Localization ◽  
Gene Knockout ◽  
Molecular Genetic ◽  
Molecular Genetic Analysis ◽  
Model Organisms ◽  
Medical Mycology ◽  
Fungal Genetics ◽  
Study Gene Expression ◽  
Fluorescent Tagging

Fungi have been long used as model organisms to investigate genetic and cellular processes. An overview is provided of how fungi function at a genetic level, including ploidy, gene structure, and gene flow by sexual and asexual processes. The tools used to study fungal genetics are then described, such techniques having widespread applications in medical mycology research. Classical genetic analysis includes the use of gene mapping by sexual crossing and tetrad analysis, and forward genetic experimentation based on mutagenesis, for which various mutant screening approaches are described. Molecular genetic analysis includes gene manipulation by transformation; different methods for gene knockout and targeting, and their application for forward and reverse genetic approaches, are outlined. Finally, molecular genetic methods used to study gene expression and function are reviewed, including use of inducible or constitutive overexpression, real-time PCR, cellular localization of gene products by fluorescent tagging, and detection of protein–protein interactions.

scholarly journals The Effects of Oleuropein on Different Clinically Types of Human Neuroblastoma Cells

Proceedings ◽  
2018 ◽  
Vol 2 (25) ◽  
pp. 1591
Author(s):  
Zekiye Altun ◽  
Efe Ozgur Serinan ◽  
Merve Tütüncü ◽  
Safiye Aktaş ◽  
Nur Olgun
Keyword(s):  
Bone Marrow ◽  
Cell Proliferation ◽  
Cell Death ◽  
Apoptotic Cell ◽  
Neuroblastoma Cell ◽  
Neuroblastoma Cells ◽  
Model Organisms ◽  
Late Relapse ◽  
Human Neuroblastoma Cells ◽  
Human Neuroblastoma

Neuroblastoma is an embryonic tumor originating from the neural crest. It accounts for 8–10% of all childhood cancers. Although Cisplatin is used in neuroblastoma treatment, it has many side effects, such as ototoxicity, nephrotoxicity, and neurotoxicity. One herbal agent that has attracted attention in recent years is oleuropein (OLE), the active component of olive leaf. This component belongs to the polyphenol group and it has antioxidant, anti-microbial, anti-inflammatory, anti-hypertensive and anti-carcinogenic effects. It has beneficial effects against neurodegeneration in both culture cells and model organisms. Oleuropein has been shown to be increased apoptosis in SH-SY5Y neuroblastoma cell line in one study. Cisplatin (cis-diaminedichloroplatinum II (CDDP) is a widely used agent for the treatment of many different human cancers in childhood and adults with antimitotic and antineoplastic properties. CDDP is the most effective chemotherapeutic agent in specially treatment of neuroblastoma. Purpose of this study was to determine whether oleuropein and CDDP have possible anti-proliferative activity in different types of human neuroblastoma cells as representing different clinical features (bone marrow metastatic LAN-5 cells and treated with chemotherapy and beam therapy CHP-134 cells representing late relapse) investigated. Human bone marrow metastatic LAN-5 and treated with chemotherapy and beam therapy CHP-134 neuroblastoma cells representing late relapse were used in this study. The effects of OLE and CDDP on LAN-5 and CHP-134 neuroblastoma cell proliferation and apoptotic cell death was investigated using WST-1 cell proliferation and Annexin-V/PI flow cytometric assays. Oleuropein and CDDP have been shown to inhibit proliferation of LAN-5 and CHP-134 neuroblastoma cells. In further studies, it is planned to investigate different cell death mechanisms by using combination of oleuropein and cisplatin in different kind of human neuroblastoma cells.

Sign in / Sign up

Export Citation Format

Share Document