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Franke A, Bayer T, Clemmesen C, Wendt F, Lehmann A, Roth O, Schneider RF. Climate challenges for fish larvae: Interactive multi-stressor effects impair acclimation potential of Atlantic herring larvae. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 953:175659. [PMID: 39181268 DOI: 10.1016/j.scitotenv.2024.175659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 08/15/2024] [Accepted: 08/18/2024] [Indexed: 08/27/2024]
Abstract
Fish early life stages are particularly vulnerable and heavily affected by changing environmental factors. The interactive effects of multiple climate change-related stressors on fish larvae remain, however, largely underexplored. As rising temperatures can increase the abundance and virulence of bacteria, we investigated the combination of a spring heat wave and bacterial exposure on the development of Atlantic herring larvae (Clupea harengus). Eggs and larvae of Western Baltic Spring-spawners were reared at a normal and high temperature ramp and exposed to Vibrio alginolyticus and V. anguillarum, respectively. Subsequently, mRNA and miRNA transcriptomes, microbiota composition, growth and survival were assessed. Both high temperature and V. alginolyticus exposure induced a major downregulation of gene expression likely impeding larval cell proliferation. In contrast, interactive effects of elevated temperature and V. alginolyticus resulted in minimal gene expression changes, indicating an impaired plastic response, which may cause cellular damage reducing survival in later larval stages. The heat wave alone or in combination with V. alginolyticus induced a notable shift in miRNA expression leading to the down- but also upregulation of predicted target genes. Moreover, both increased temperature and the Vibrio exposures significantly altered the larval microbiota composition, with warming reducing microbial richness and diversity. The outcomes of this study highlight the high sensitivity of herring early life stages towards multiple climate change-related stressors. Our results indicate that interactive effects of rapidly changing environmental factors may exceed the larval stress threshold impairing essential acclimation responses, which may contribute to the ongoing recruitment decline of Western Baltic Spring-Spawning herring.
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Affiliation(s)
- Andrea Franke
- Helmholtz Institute for Functional Marine Biodiversity at the University of Oldenburg (HIFMB), Im Technologiepark 5, 26129 Oldenburg, Germany; Alfred-Wegener-Institute, Helmholtz-Centre for Polar and Marine Research (AWI), Am Handelshafen 12, 27570 Bremerhaven, Germany.
| | - Till Bayer
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstraße 1-3, 24148 Kiel, Germany.
| | - Catriona Clemmesen
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstraße 1-3, 24148 Kiel, Germany.
| | - Fabian Wendt
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstraße 1-3, 24148 Kiel, Germany.
| | - Andreas Lehmann
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstraße 1-3, 24148 Kiel, Germany.
| | - Olivia Roth
- Marine Evolutionary Biology, Zoological Institute, Am Botanischen Garten 1-9, Kiel University, 24118 Kiel, Germany.
| | - Ralf F Schneider
- Marine Evolutionary Biology, Zoological Institute, Am Botanischen Garten 1-9, Kiel University, 24118 Kiel, Germany.
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Kutzner CE, Bauer KC, Lackmann JW, Acton RJ, Sarkar A, Pokrzywa W, Hoppe T. Optogenetic induction of mechanical muscle stress identifies myosin regulatory ubiquitin ligase NHL-1 in C. elegans. Nat Commun 2024; 15:6879. [PMID: 39128917 PMCID: PMC11317515 DOI: 10.1038/s41467-024-51069-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Accepted: 07/26/2024] [Indexed: 08/13/2024] Open
Abstract
Mechanical stress during muscle contraction is a constant threat to proteome integrity. However, there is a lack of experimental systems to identify critical proteostasis regulators under mechanical stress conditions. Here, we present the transgenic Caenorhabditis elegans model OptIMMuS (Optogenetic Induction of Mechanical Muscle Stress) to study changes in the proteostasis network associated with mechanical forces. Repeated blue light exposure of a muscle-expressed Chlamydomonas rheinhardii channelrhodopsin-2 variant results in sustained muscle contraction and mechanical stress. Using OptIMMuS, combined with proximity labeling and mass spectrometry, we identify regulators that cooperate with the myosin-directed chaperone UNC-45 in muscle proteostasis. One of these is the TRIM E3 ligase NHL-1, which interacts with UNC-45 and muscle myosin in genetic epistasis and co-immunoprecipitation experiments. We provide evidence that the ubiquitylation activity of NHL-1 regulates myosin levels and functionality under mechanical stress. In the future, OptIMMuS will help to identify muscle-specific proteostasis regulators of therapeutic relevance.
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Affiliation(s)
- Carl Elias Kutzner
- Institute for Genetics, University of Cologne, Cologne, Germany
- Cologne Excellence Cluster for Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Karen Carolyn Bauer
- Institute for Genetics, University of Cologne, Cologne, Germany
- Cologne Excellence Cluster for Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Jan-Wilm Lackmann
- Cologne Excellence Cluster for Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Richard James Acton
- Human Developmental Biology Initiative (HDBI) at Babraham Institute, Cambridge, United Kingdom
| | - Anwesha Sarkar
- Laboratory of Protein Metabolism, International Institute of Molecular and Cell Biology in Warsaw, Warsaw, Poland
| | - Wojciech Pokrzywa
- Laboratory of Protein Metabolism, International Institute of Molecular and Cell Biology in Warsaw, Warsaw, Poland
| | - Thorsten Hoppe
- Institute for Genetics, University of Cologne, Cologne, Germany.
- Cologne Excellence Cluster for Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany.
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany.
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Eligulashvili A, Gordon M, Lee JS, Lee J, Mehrotra-Varma S, Mehrotra-Varma J, Hsu K, Hilliard I, Lee K, Li A, Essibayi MA, Yee J, Altschul DJ, Eskandar E, Mehler MF, Duong TQ. Long-term outcomes of hospitalized patients with SARS-CoV-2/COVID-19 with and without neurological involvement: 3-year follow-up assessment. PLoS Med 2024; 21:e1004263. [PMID: 38573873 PMCID: PMC10994395 DOI: 10.1371/journal.pmed.1004263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 02/28/2024] [Indexed: 04/06/2024] Open
Abstract
BACKGROUND Acute neurological manifestation is a common complication of acute Coronavirus Disease 2019 (COVID-19) disease. This retrospective cohort study investigated the 3-year outcomes of patients with and without significant neurological manifestations during initial COVID-19 hospitalization. METHODS AND FINDINGS Patients hospitalized for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection between 03/01/2020 and 4/16/2020 in the Montefiore Health System in the Bronx, an epicenter of the early pandemic, were included. Follow-up data was captured up to 01/23/2023 (3 years post-COVID-19). This cohort consisted of 414 patients with COVID-19 with significant neurological manifestations and 1,199 propensity-matched patients (for age and COVID-19 severity score) with COVID-19 without neurological manifestations. Neurological involvement during the acute phase included acute stroke, new or recrudescent seizures, anatomic brain lesions, presence of altered mentation with evidence for impaired cognition or arousal, and neuro-COVID-19 complex (headache, anosmia, ageusia, chemesthesis, vertigo, presyncope, paresthesias, cranial nerve abnormalities, ataxia, dysautonomia, and skeletal muscle injury with normal orientation and arousal signs). There were no significant group differences in female sex composition (44.93% versus 48.21%, p = 0.249), ICU and IMV status, white, not Hispanic (6.52% versus 7.84%, p = 0.380), and Hispanic (33.57% versus 38.20%, p = 0.093), except black non-Hispanic (42.51% versus 36.03%, p = 0.019). Primary outcomes were mortality, stroke, heart attack, major adverse cardiovascular events (MACE), reinfection, and hospital readmission post-discharge. Secondary outcomes were neuroimaging findings (hemorrhage, active and prior stroke, mass effect, microhemorrhages, white matter changes, microvascular disease (MVD), and volume loss). More patients in the neurological cohort were discharged to acute rehabilitation (10.39% versus 3.34%, p < 0.001) or skilled nursing facilities (35.75% versus 25.35%, p < 0.001) and fewer to home (50.24% versus 66.64%, p < 0.001) than matched controls. Incidence of readmission for any reason (65.70% versus 60.72%, p = 0.036), stroke (6.28% versus 2.34%, p < 0.001), and MACE (20.53% versus 16.51%, p = 0.032) was higher in the neurological cohort post-discharge. Per Kaplan-Meier univariate survival curve analysis, such patients in the neurological cohort were more likely to die post-discharge compared to controls (hazard ratio: 2.346, (95% confidence interval (CI) [1.586, 3.470]; p < 0.001)). Across both cohorts, the major causes of death post-discharge were heart disease (13.79% neurological, 15.38% control), sepsis (8.63%, 17.58%), influenza and pneumonia (13.79%, 9.89%), COVID-19 (10.34%, 7.69%), and acute respiratory distress syndrome (ARDS) (10.34%, 6.59%). Factors associated with mortality after leaving the hospital involved the neurological cohort (odds ratio (OR): 1.802 (95% CI [1.237, 2.608]; p = 0.002)), discharge disposition (OR: 1.508 (95% CI [1.276, 1.775]; p < 0.001)), congestive heart failure (OR: 2.281 (95% CI [1.429, 3.593]; p < 0.001)), higher COVID-19 severity score (OR: 1.177 (95% CI [1.062, 1.304]; p = 0.002)), and older age (OR: 1.027 (95% CI [1.010, 1.044]; p = 0.002)). There were no group differences in radiological findings, except that the neurological cohort showed significantly more age-adjusted brain volume loss (p = 0.045) than controls. The study's patient cohort was limited to patients infected with COVID-19 during the first wave of the pandemic, when hospitals were overburdened, vaccines were not yet available, and treatments were limited. Patient profiles might differ when interrogating subsequent waves. CONCLUSIONS Patients with COVID-19 with neurological manifestations had worse long-term outcomes compared to matched controls. These findings raise awareness and the need for closer monitoring and timely interventions for patients with COVID-19 with neurological manifestations, as their disease course involving initial neurological manifestations is associated with enhanced morbidity and mortality.
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Affiliation(s)
- Anna Eligulashvili
- Department of Radiology, Montefiore Health System and Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Moshe Gordon
- Department of Radiology, Montefiore Health System and Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Jimmy S. Lee
- Department of Radiology, Montefiore Health System and Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Jeylin Lee
- Department of Radiology, Montefiore Health System and Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Shiv Mehrotra-Varma
- Department of Radiology, Montefiore Health System and Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Jai Mehrotra-Varma
- Department of Radiology, Montefiore Health System and Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Kevin Hsu
- Department of Radiology, New York University Grossman School of Medicine, New York, New York, United States of America
| | - Imanyah Hilliard
- Department of Radiology, Montefiore Health System and Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Kristen Lee
- Department of Radiology, Montefiore Health System and Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Arleen Li
- Department of Radiology, Montefiore Health System and Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Muhammed Amir Essibayi
- Department of Neurological Surgery, Montefiore Health System and Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Judy Yee
- Department of Radiology, Montefiore Health System and Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - David J. Altschul
- Department of Neurological Surgery, Montefiore Health System and Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Emad Eskandar
- Department of Neurological Surgery, Montefiore Health System and Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Mark F. Mehler
- Department of Neurology, Montefiore Health System and Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Tim Q. Duong
- Department of Radiology, Montefiore Health System and Albert Einstein College of Medicine, Bronx, New York, United States of America
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Pessa JC, Joutsen J, Sistonen L. Transcriptional reprogramming at the intersection of the heat shock response and proteostasis. Mol Cell 2024; 84:80-93. [PMID: 38103561 DOI: 10.1016/j.molcel.2023.11.024] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 11/16/2023] [Accepted: 11/20/2023] [Indexed: 12/19/2023]
Abstract
Cellular homeostasis is constantly challenged by a myriad of extrinsic and intrinsic stressors. To mitigate the stress-induced damage, cells activate transient survival programs. The heat shock response (HSR) is an evolutionarily well-conserved survival program that is activated in response to proteotoxic stress. The HSR encompasses a dual regulation of transcription, characterized by rapid activation of genes encoding molecular chaperones and concomitant global attenuation of non-chaperone genes. Recent genome-wide approaches have delineated the molecular depth of stress-induced transcriptional reprogramming. The dramatic rewiring of gene and enhancer networks is driven by key transcription factors, including heat shock factors (HSFs), that together with chromatin-modifying enzymes remodel the 3D chromatin architecture, determining the selection of either gene activation or repression. Here, we highlight the current advancements of molecular mechanisms driving transcriptional reprogramming during acute heat stress. We also discuss the emerging implications of HSF-mediated stress signaling in the context of physiological and pathological conditions.
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Affiliation(s)
- Jenny C Pessa
- Faculty of Science and Engineering, Cell Biology, Åbo Akademi University, Turku, Finland; Turku Bioscience Centre, University of Turku and Åbo Akademi University, Turku, Finland
| | - Jenny Joutsen
- Department of Pathology, Lapland Central Hospital, Lapland Wellbeing Services County, Rovaniemi, Finland
| | - Lea Sistonen
- Faculty of Science and Engineering, Cell Biology, Åbo Akademi University, Turku, Finland; Turku Bioscience Centre, University of Turku and Åbo Akademi University, Turku, Finland.
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Ali A, Garde R, Schaffer OC, Bard JAM, Husain K, Kik SK, Davis KA, Luengo-Woods S, Igarashi MG, Drummond DA, Squires AH, Pincus D. Adaptive preservation of orphan ribosomal proteins in chaperone-dispersed condensates. Nat Cell Biol 2023; 25:1691-1703. [PMID: 37845327 PMCID: PMC10868727 DOI: 10.1038/s41556-023-01253-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Accepted: 09/12/2023] [Indexed: 10/18/2023]
Abstract
Ribosome biogenesis is among the most resource-intensive cellular processes, with ribosomal proteins accounting for up to half of all newly synthesized proteins in eukaryotic cells. During stress, cells shut down ribosome biogenesis in part by halting rRNA synthesis, potentially leading to massive accumulation of aggregation-prone 'orphan' ribosomal proteins (oRPs). Here we show that, during heat shock in yeast and human cells, oRPs accumulate as reversible peri-nucleolar condensates recognized by the Hsp70 co-chaperone Sis1/DnaJB6. oRP condensates are liquid-like in cell-free lysate but solidify upon depletion of Sis1 or inhibition of Hsp70. When cells recover from heat shock, oRP condensates disperse in a Sis1- and Hsp70-dependent manner, and the oRP constituents are incorporated into functional ribosomes in the cytosol, enabling cells to efficiently resume growth. Preserving biomolecules in reversible condensates-like mRNAs in cytosolic stress granules and oRPs at the nucleolar periphery-may be a primary function of the Hsp70 chaperone system.
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Affiliation(s)
- Asif Ali
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL, USA.
| | - Rania Garde
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL, USA
- Committee on Genetics, Genomics, and Systems Biology, University of Chicago, Chicago, IL, USA
| | - Olivia C Schaffer
- Pritzker School for Molecular Engineering, University of Chicago, Chicago, IL, USA
| | - Jared A M Bard
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, USA
| | - Kabir Husain
- Department of Physics, University of Chicago, Chicago, IL, USA
| | - Samantha Keyport Kik
- Committee on Genetics, Genomics, and Systems Biology, University of Chicago, Chicago, IL, USA
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, USA
| | - Kathleen A Davis
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL, USA
| | - Sofia Luengo-Woods
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL, USA
| | - Maya G Igarashi
- Graduate Program in Biophysical Sciences, University of Chicago, Chicago, IL, USA
| | - D Allan Drummond
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, USA
- Department of Medicine, Section of Genetic Medicine, University of Chicago, Chicago, IL, USA
- Institute for Biophysical Dynamics, University of Chicago, Chicago, IL, USA
- Center for Physics of Evolving Systems, University of Chicago, Chicago, IL, USA
| | - Allison H Squires
- Pritzker School for Molecular Engineering, University of Chicago, Chicago, IL, USA
- Institute for Biophysical Dynamics, University of Chicago, Chicago, IL, USA
- Center for Physics of Evolving Systems, University of Chicago, Chicago, IL, USA
| | - David Pincus
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL, USA.
- Institute for Biophysical Dynamics, University of Chicago, Chicago, IL, USA.
- Center for Physics of Evolving Systems, University of Chicago, Chicago, IL, USA.
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Lan C, Kim J, Ulferts S, Aprile-Garcia F, Weyrauch S, Anandamurugan A, Grosse R, Sawarkar R, Reinhardt A, Hugel T. Quantitative real-time in-cell imaging reveals heterogeneous clusters of proteins prior to condensation. Nat Commun 2023; 14:4831. [PMID: 37582808 PMCID: PMC10427612 DOI: 10.1038/s41467-023-40540-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Accepted: 07/26/2023] [Indexed: 08/17/2023] Open
Abstract
Our current understanding of biomolecular condensate formation is largely based on observing the final near-equilibrium condensate state. Despite expectations from classical nucleation theory, pre-critical protein clusters were recently shown to form under subsaturation conditions in vitro; if similar long-lived clusters comprising more than a few molecules are also present in cells, our understanding of the physical basis of biological phase separation may fundamentally change. Here, we combine fluorescence microscopy with photobleaching analysis to quantify the formation of clusters of NELF proteins in living, stressed cells. We categorise small and large clusters based on their dynamics and their response to p38 kinase inhibition. We find a broad distribution of pre-condensate cluster sizes and show that NELF protein cluster formation can be explained as non-classical nucleation with a surprisingly flat free-energy landscape for a wide range of sizes and an inhibition of condensation in unstressed cells.
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Affiliation(s)
- Chenyang Lan
- Institute of Physical Chemistry, University of Freiburg, Freiburg, Germany
- BIOSS and CIBSS Signalling Research Centres, University of Freiburg, Freiburg, Germany
- PicoQuant GmbH, Rudower Chaussee 29, 12489, Berlin, Germany
| | - Juhyeong Kim
- Institute of Physical Chemistry, University of Freiburg, Freiburg, Germany
| | - Svenja Ulferts
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Freiburg, Freiburg, Germany
| | | | - Sophie Weyrauch
- Institute of Physical Chemistry, University of Freiburg, Freiburg, Germany
- Spemann Graduate School of Biology and Medicine (SGBM), University of Freiburg, Freiburg, Germany
- Faculty of Chemistry and Pharmacology, University of Freiburg, Freiburg, Germany
| | | | - Robert Grosse
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Freiburg, Freiburg, Germany
| | - Ritwick Sawarkar
- Medical Research Council (MRC), University of Cambridge, Cambridge, CB2 1QR, United Kingdom
| | - Aleks Reinhardt
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, United Kingdom.
| | - Thorsten Hugel
- Institute of Physical Chemistry, University of Freiburg, Freiburg, Germany.
- BIOSS and CIBSS Signalling Research Centres, University of Freiburg, Freiburg, Germany.
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Ring stage dormancy of Plasmodium falciparum tolerant to artemisinin and its analogues - A genetically regulated "Sleeping Beauty". Int J Parasitol Drugs Drug Resist 2023; 21:61-64. [PMID: 36708651 PMCID: PMC9883618 DOI: 10.1016/j.ijpddr.2023.01.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 01/11/2023] [Accepted: 01/13/2023] [Indexed: 01/18/2023]
Abstract
The appearance in 2008 in western Cambodia of Plasmodium falciparum tolerant to artemisinin, defined by longer parasite clearance time following drug administration and in vitro by a slightly higher survival rate of the ring stage after a 3-h treatment with 700 nM artemisinin (or analogues, collectively termed ART), has raised concerns of the possible loss of this frontline antimalarial [used in the form of an artemisinin combination therapy (ACT)], with its low IC50 value against the ring stage and pleiotropic pro-drug/poison property. The key genetic marker of ART tolerance phenotype is a number of non-synonymous mutations in Pfkelch13 propeller domain. This results in defective assembly at the ring stage of a cytostome structure located at cytoplasmic side of the parasite membrane required for invagination of a double-membrane endosome carrying host cytosol haemoglobin to the digestive vacuole. The consequential deprivation of amino acids initiates ring stage parasites bearing the causal mutations in PfK13 (or other key cytostome components) entry into a dormant state ("Sleeping Beauty"), which, after a duration longer than that the short-lived ART, "Sleeping Beauty" ring parasite resumes its normal, but accelerated, development to maintain the 48-h intra-erythrocytic life-cycle. We posit that when ART-tolerant P. falciparum has acquired under ART stress the causative PfK13 mutation (not obligatory if mutations occur in other critical cytostome components), together with other necessary mutations to adjust to the new normalcy and to provide survival competitiveness, ART-tolerant parasite has now evolved into a genetically programmed "Sleeping Beauty". The onus of preventing the spread of ART-tolerant P. falciparum lies with the efficacy of ACT partner drug, hence the recommendation of a triple ACT (TACT). Nevertheless, attention should also be focussed on understanding the mechanisms of dormancy, such as induction, maintenance and recovery, to enable discovery and development of novel antimalarials targeting this unique parasite stage.
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