1
|
Li H, Qian X, Mohanram H, Han X, Qi H, Zou G, Yuan F, Miserez A, Liu T, Yang Q, Gao H, Yu J. Self-assembly of peptide nanocapsules by a solvent concentration gradient. Nat Nanotechnol 2024:10.1038/s41565-024-01654-w. [PMID: 38671050 DOI: 10.1038/s41565-024-01654-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 03/12/2024] [Indexed: 04/28/2024]
Abstract
Biological systems can create materials with intricate structures and specialized functions. In comparison, precise control of structures in human-made materials has been challenging. Here we report on insect cuticle peptides that spontaneously form nanocapsules through a single-step solvent exchange process, where the concentration gradient resulting from the mixing of water and acetone drives the localization and self-assembly of the peptides into hollow nanocapsules. The underlying driving force is found to be the intrinsic affinity of the peptides for a particular solvent concentration, while the diffusion of water and acetone creates a gradient interface that triggers peptide localization and self-assembly. This gradient-mediated self-assembly offers a transformative pathway towards simple generation of drug delivery systems based on peptide nanocapsules.
Collapse
Affiliation(s)
- Haopeng Li
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, Singapore
- MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, Dalian, China
| | - Xuliang Qian
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, Singapore
| | - Harini Mohanram
- School of Biological Sciences, Division of Structural and Computational Biology, Nanyang Technological University, Singapore, Singapore
| | - Xiao Han
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, Singapore
| | - Huitang Qi
- MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, Dalian, China
| | - Guijin Zou
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, Singapore
- Institute of High Performance Computing, A*STAR, Singapore, Singapore
| | - Fenghou Yuan
- MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, Dalian, China
| | - Ali Miserez
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, Singapore
- Biological and Biomimetic Material Laboratory (BBML), Center for Sustainable Materials (SusMat), School of Materials Science and Engineering, Nanyang Technological University, Singapore, Singapore
| | - Tian Liu
- MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, Dalian, China.
| | - Qing Yang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.
- Guangdong Laboratory of Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China.
| | - Huajian Gao
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, Singapore.
- Institute of High Performance Computing, A*STAR, Singapore, Singapore.
- Mechano-X Institute, Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing, China.
| | - Jing Yu
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, Singapore.
- Institute for Digital Molecular Analytics and Science, Nanyang Technological University, Singapore, Singapore.
| |
Collapse
|
2
|
Guo K, Liu M, Vella D, Suresh S, Hsia KJ. Dehydration-induced corrugated folding in Rhapis excelsa plant leaves. Proc Natl Acad Sci U S A 2024; 121:e2320259121. [PMID: 38588439 PMCID: PMC11047117 DOI: 10.1073/pnas.2320259121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Accepted: 02/28/2024] [Indexed: 04/10/2024] Open
Abstract
Plant leaves, whose remarkable ability for morphogenesis results in a wide range of petal and leaf shapes in response to environmental cues, have inspired scientific studies as well as the development of engineering structures and devices. Although some typical shape changes in plants and the driving force for such shape evolution have been extensively studied, there remain many poorly understood mechanisms, characteristics, and principles associated with the vast array of shape formation of plant leaves in nature. Here, we present a comprehensive study that combines experiment, theory, and numerical simulations of one such topic-the mechanics and mechanisms of corrugated leaf folding induced by differential shrinking in Rhapis excelsa. Through systematic measurements of the dehydration process in sectioned leaves, we identify a linear correlation between change in the leaf-folding angle and water loss. Building on experimental findings, we develop a generalized model that provides a scaling relationship for water loss in sectioned leaves. Furthermore, our study reveals that corrugated folding induced by dehydration in R. excelsa leaves is achieved by the deformation of a structural architecture-the "hinge" cells. Utilizing such connections among structure, morphology, environmental stimuli, and mechanics, we fabricate several biomimetic machines, including a humidity sensor and morphing devices capable of folding in response to dehydration. The mechanisms of corrugated folding in R. excelsa identified in this work provide a general understanding of the interactions between plant leaves and water. The actuation mechanisms identified in this study also provide insights into the rational design of soft machines.
Collapse
Affiliation(s)
- Kexin Guo
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore639798, Singapore
| | - Mingchao Liu
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore639798, Singapore
- Department of Mechanical Engineering, University of Birmingham, BirminghamB15 2TT, United Kingdom
| | - Dominic Vella
- Mathematical Institute, University of Oxford, OxfordOX2 6GG, United Kingdom
| | - Subra Suresh
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore639798, Singapore
- Division of Engineering, Brown University, Providence, RI02912
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA02139
| | - K. Jimmy Hsia
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore639798, Singapore
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore639798, Singapore
| |
Collapse
|
3
|
Tomlin CM, Rajaraman S, Sebesta JT, Scheen AC, Bendiksby M, Low YW, Salojärvi J, Michael TP, Albert VA, Lindqvist C. Allopolyploid origin and diversification of the Hawaiian endemic mints. Nat Commun 2024; 15:3109. [PMID: 38600100 PMCID: PMC11006916 DOI: 10.1038/s41467-024-47247-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 03/26/2024] [Indexed: 04/12/2024] Open
Abstract
Island systems provide important contexts for studying processes underlying lineage migration, species diversification, and organismal extinction. The Hawaiian endemic mints (Lamiaceae family) are the second largest plant radiation on the isolated Hawaiian Islands. We generated a chromosome-scale reference genome for one Hawaiian species, Stenogyne calaminthoides, and resequenced 45 relatives, representing 34 species, to uncover the continental origins of this group and their subsequent diversification. We further resequenced 109 individuals of two Stenogyne species, and their purported hybrids, found high on the Mauna Kea volcano on the island of Hawai'i. The three distinct Hawaiian genera, Haplostachys, Phyllostegia, and Stenogyne, are nested inside a fourth genus, Stachys. We uncovered four independent polyploidy events within Stachys, including one allopolyploidy event underlying the Hawaiian mints and their direct western North American ancestors. While the Hawaiian taxa may have principally diversified by parapatry and drift in small and fragmented populations, localized admixture may have played an important role early in lineage diversification. Our genomic analyses provide a view into how organisms may have radiated on isolated island chains, settings that provided one of the principal natural laboratories for Darwin's thinking about the evolutionary process.
Collapse
Affiliation(s)
- Crystal M Tomlin
- Department of Biological Sciences, University at Buffalo, New York, USA
| | - Sitaram Rajaraman
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
- Organismal and Evolutionary Biology Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | | | | | - Mika Bendiksby
- Natural History Museum, University of Oslo, Oslo, Norway
| | - Yee Wen Low
- Singapore Botanic Gardens, National Parks Board, Singapore, Singapore
| | - Jarkko Salojärvi
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
- Organismal and Evolutionary Biology Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Todd P Michael
- The Plant Molecular and Cellular Biology Laboratory, Salk Institute for Biological Studies, La Jolla, California, USA
| | - Victor A Albert
- Department of Biological Sciences, University at Buffalo, New York, USA.
| | | |
Collapse
|
4
|
Zeng J, Loi GWZ, Saipuljumri EN, Romero Durán MA, Silva-García O, Perez-Aguilar JM, Baizabal-Aguirre VM, Lo CH. Peptide-based allosteric inhibitor targets TNFR1 conformationally active region and disables receptor-ligand signaling complex. Proc Natl Acad Sci U S A 2024; 121:e2308132121. [PMID: 38551841 PMCID: PMC10998571 DOI: 10.1073/pnas.2308132121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 01/23/2024] [Indexed: 04/02/2024] Open
Abstract
Tumor necrosis factor (TNF) receptor 1 (TNFR1) plays a pivotal role in mediating TNF induced downstream signaling and regulating inflammatory response. Recent studies have suggested that TNFR1 activation involves conformational rearrangements of preligand assembled receptor dimers and targeting receptor conformational dynamics is a viable strategy to modulate TNFR1 signaling. Here, we used a combination of biophysical, biochemical, and cellular assays, as well as molecular dynamics simulation to show that an anti-inflammatory peptide (FKCRRWQWRMKK), which we termed FKC, inhibits TNFR1 activation allosterically by altering the conformational states of the receptor dimer without blocking receptor-ligand interaction or disrupting receptor dimerization. We also demonstrated the efficacy of FKC by showing that the peptide inhibits TNFR1 signaling in HEK293 cells and attenuates inflammation in mice with intraperitoneal TNF injection. Mechanistically, we found that FKC binds to TNFR1 cysteine-rich domains (CRD2/3) and perturbs the conformational dynamics required for receptor activation. Importantly, FKC increases the frequency in the opening of both CRD2/3 and CRD4 in the receptor dimer, as well as induces a conformational opening in the cytosolic regions of the receptor. This results in an inhibitory conformational state that impedes the recruitment of downstream signaling molecules. Together, these data provide evidence on the feasibility of targeting TNFR1 conformationally active region and open new avenues for receptor-specific inhibition of TNFR1 signaling.
Collapse
Affiliation(s)
- Jialiu Zeng
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore308232, Singapore
| | - Gavin Wen Zhao Loi
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore308232, Singapore
| | - Eka Norfaishanty Saipuljumri
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore308232, Singapore
- School of Applied Science, Republic Polytechnic, Singapore738964, Singapore
| | - Marco Antonio Romero Durán
- Centro Multidisciplinario de Estudios en Biotecnología, Facultad de Medicina Veterinaria y Zootecnia, Universidad Michoacana de San Nicolás de Hidalgo, Morelia58893, México
| | - Octavio Silva-García
- Centro Multidisciplinario de Estudios en Biotecnología, Facultad de Medicina Veterinaria y Zootecnia, Universidad Michoacana de San Nicolás de Hidalgo, Morelia58893, México
| | - Jose Manuel Perez-Aguilar
- School of Chemical Sciences, Meritorious Autonomous University of Puebla, University City, Puebla72570, México
| | - Víctor M. Baizabal-Aguirre
- Centro Multidisciplinario de Estudios en Biotecnología, Facultad de Medicina Veterinaria y Zootecnia, Universidad Michoacana de San Nicolás de Hidalgo, Morelia58893, México
| | - Chih Hung Lo
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore308232, Singapore
| |
Collapse
|
5
|
Zhong Y, Guo S, Thong S, Schlundt J, Kwa AL. First report of environmental bla PAC-1-carrying Aeromonas enteropelogenes. Microbiol Spectr 2023; 11:e0139123. [PMID: 37909756 PMCID: PMC10714797 DOI: 10.1128/spectrum.01391-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Accepted: 09/25/2023] [Indexed: 11/03/2023] Open
Abstract
The bla PAC-1 has been reported in Central Asia and Europe countries like Afghanistan and France in Aeromonas caviae and Pseudomonas aeruginosa strains from animals and patients, respectively. However, there is no record of bla PAC-1-carrying strain from the natural environment, and bla PAC-1-carrying Aeromonas has not been reported in the Asia Pacific. Here, we report the first known enviromental bla PAC-1-carrying Aeromonas enteropelogenes in the world from reservoir water in Singapore. We have performed a comprehensive genetic environment alignment and comparison of bla PAC-1 between our strain and other strains from different countries and sources and found the bla PAC-1 located on a highly conserved gene cluster. We suggest that environmental Aeromonas strains may act as a hidden reservoir involved in the circulating of bla PAC-1. The finding of conserved bla PAC-1 cluster also suggested the existence of multiple transmission pathways of bla PAC-1 in the Asia-Pacific region, involving multiple sources and different species.
Collapse
Affiliation(s)
- Yang Zhong
- Department of Pharmacy, Singapore General Hospital, Singapore, Singapore
- Department of Clinical Translational Research, Singapore General Hospital, Singapore, Singapore
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore, Singapore
| | - Siyao Guo
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore, Singapore
| | - Shuhua Thong
- Department of Pharmacy, Singapore General Hospital, Singapore, Singapore
| | - Joergen Schlundt
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore, Singapore
| | - Andrea L. Kwa
- Department of Pharmacy, Singapore General Hospital, Singapore, Singapore
- Emerging Infectious Diseases, Duke-NUS Medical School, Singapore, Singapore
- SingHealth Duke-NUS Medicine Academic Clinical Programme, Singapore, Singapore
| |
Collapse
|
6
|
Sun F, Fang C, Shao X, Gao H, Lin Y. A mechanism-based theory of cellular and tissue plasticity. Proc Natl Acad Sci U S A 2023; 120:e2305375120. [PMID: 37871208 PMCID: PMC10622945 DOI: 10.1073/pnas.2305375120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 09/12/2023] [Indexed: 10/25/2023] Open
Abstract
Plastic deformation in cells and tissues has been found to play crucial roles in collective cell migration, cancer metastasis, and morphogenesis. However, the fundamental question of how plasticity is initiated in individual cells and then propagates within the tissue remains elusive. Here, we develop a mechanism-based theory of cellular and tissue plasticity that accounts for all key processes involved, including the activation and development of active contraction at different scales as well as the formation of endocytic vesicles on cell junctions and show that this theory achieves quantitative agreement with all existing experiments. Specifically, it reveals that, in response to optical or mechanical stimuli, the myosin contraction and thermal fluctuation-assisted formation and pinching of endocytic vesicles could lead to permanent shortening of cell junctions and that such plastic constriction can stretch neighboring cells and trigger their active contraction through mechanochemical feedbacks and eventually their plastic deformations as well. Our theory predicts that endocytic vesicles with a size around 1 to 2 µm will most likely be formed and a higher irreversible shortening of cell junctions could be achieved if a long stimulation is split into multiple short ones, all in quantitative agreement with experiments. Our analysis also shows that constriction of cells in tissue can undergo elastic/unratcheted to plastic/ratcheted transition as the magnitude and duration of active contraction increases, ultimately resulting in the propagation of plastic deformation waves within the monolayer with a constant speed which again is consistent with experimental observations.
Collapse
Affiliation(s)
- Fuqiang Sun
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China
- The University of Hong Kong-Shenzhen Institute of Research and Innovation, Shenzhen518057, China
| | - Chao Fang
- School of Science, Harbin Institute of Technology, Shenzhen518055, China
| | - Xueying Shao
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Hong Kong, China
| | - Huajian Gao
- College of Engineering, Nanyang Technological University, Singapore639798, Singapore
| | - Yuan Lin
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China
- The University of Hong Kong-Shenzhen Institute of Research and Innovation, Shenzhen518057, China
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Hong Kong, China
| |
Collapse
|
7
|
Chia XW, Tan JK, Ang LF, Kamigaki T, Makino H. Emergence of cortical network motifs for short-term memory during learning. Nat Commun 2023; 14:6869. [PMID: 37898638 PMCID: PMC10613236 DOI: 10.1038/s41467-023-42609-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 10/16/2023] [Indexed: 10/30/2023] Open
Abstract
Learning of adaptive behaviors requires the refinement of coordinated activity across multiple brain regions. However, how neural communications develop during learning remains poorly understood. Here, using two-photon calcium imaging, we simultaneously recorded the activity of layer 2/3 excitatory neurons in eight regions of the mouse dorsal cortex during learning of a delayed-response task. Across learning, while global functional connectivity became sparser, there emerged a subnetwork comprising of neurons in the anterior lateral motor cortex (ALM) and posterior parietal cortex (PPC). Neurons in this subnetwork shared a similar choice code during action preparation and formed recurrent functional connectivity across learning. Suppression of PPC activity disrupted choice selectivity in ALM and impaired task performance. Recurrent neural networks reconstructed from ALM activity revealed that PPC-ALM interactions rendered choice-related attractor dynamics more stable. Thus, learning constructs cortical network motifs by recruiting specific inter-areal communication channels to promote efficient and robust sensorimotor transformation.
Collapse
Affiliation(s)
- Xin Wei Chia
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, 308232, Singapore
| | - Jian Kwang Tan
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, 308232, Singapore
| | - Lee Fang Ang
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, 308232, Singapore
| | - Tsukasa Kamigaki
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, 308232, Singapore
| | - Hiroshi Makino
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, 308232, Singapore.
| |
Collapse
|
8
|
Koh DHZ, Naito T, Na M, Yeap YJ, Rozario P, Zhong FL, Lim KL, Saheki Y. Visualization of accessible cholesterol using a GRAM domain-based biosensor. Nat Commun 2023; 14:6773. [PMID: 37880244 PMCID: PMC10600248 DOI: 10.1038/s41467-023-42498-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Accepted: 10/12/2023] [Indexed: 10/27/2023] Open
Abstract
Cholesterol is important for membrane integrity and cell signaling, and dysregulation of the distribution of cellular cholesterol is associated with numerous diseases, including neurodegenerative disorders. While regulated transport of a specific pool of cholesterol, known as "accessible cholesterol", contributes to the maintenance of cellular cholesterol distribution and homeostasis, tools to monitor accessible cholesterol in live cells remain limited. Here, we engineer a highly sensitive accessible cholesterol biosensor by taking advantage of the cholesterol-sensing element (the GRAM domain) of an evolutionarily conserved lipid transfer protein, GRAMD1b. Using this cholesterol biosensor, which we call GRAM-W, we successfully visualize in real time the distribution of accessible cholesterol in many different cell types, including human keratinocytes and iPSC-derived neurons, and show differential dependencies on cholesterol biosynthesis and uptake for maintaining levels of accessible cholesterol. Furthermore, we combine GRAM-W with a dimerization-dependent fluorescent protein (ddFP) and establish a strategy for the ultrasensitive detection of accessible plasma membrane cholesterol. These tools will allow us to obtain important insights into the molecular mechanisms by which the distribution of cellular cholesterol is regulated.
Collapse
Affiliation(s)
- Dylan Hong Zheng Koh
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, 308232, Singapore
| | - Tomoki Naito
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, 308232, Singapore
| | - Minyoung Na
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, 308232, Singapore
| | - Yee Jie Yeap
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, 308232, Singapore
| | - Pritisha Rozario
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, 308232, Singapore
| | - Franklin L Zhong
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, 308232, Singapore
- Skin Research Institute of Singapore (SRIS), Singapore, 308232, Singapore
| | - Kah-Leong Lim
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, 308232, Singapore
- National Neuroscience Institute, Singapore, 308433, Singapore
| | - Yasunori Saheki
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, 308232, Singapore.
- Institute of Resource Development and Analysis, Kumamoto University, Kumamoto, 860-0811, Japan.
| |
Collapse
|
9
|
Naito T, Yang H, Koh DHZ, Mahajan D, Lu L, Saheki Y. Regulation of cellular cholesterol distribution via non-vesicular lipid transport at ER-Golgi contact sites. Nat Commun 2023; 14:5867. [PMID: 37735529 PMCID: PMC10514280 DOI: 10.1038/s41467-023-41213-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Accepted: 08/28/2023] [Indexed: 09/23/2023] Open
Abstract
Abnormal distribution of cellular cholesterol is associated with numerous diseases, including cardiovascular and neurodegenerative diseases. Regulated transport of cholesterol is critical for maintaining its proper distribution in the cell, yet the underlying mechanisms remain unclear. Here, we show that lipid transfer proteins, namely ORP9, OSBP, and GRAMD1s/Asters (GRAMD1a/GRAMD1b/GRAMD1c), control non-vesicular cholesterol transport at points of contact between the ER and the trans-Golgi network (TGN), thereby maintaining cellular cholesterol distribution. ORP9 localizes to the TGN via interaction between its tandem α-helices and ORP10/ORP11. ORP9 extracts PI4P from the TGN to prevent its overaccumulation and suppresses OSBP-mediated PI4P-driven cholesterol transport to the Golgi. By contrast, GRAMD1s transport excess cholesterol from the Golgi to the ER, thereby preventing its build-up. Cells lacking ORP9 exhibit accumulation of cholesterol at the Golgi, which is further enhanced by additional depletion of GRAMD1s with major accumulation in the plasma membrane. This is accompanied by chronic activation of the SREBP-2 signalling pathway. Our findings reveal the importance of regulated lipid transport at ER-Golgi contacts for maintaining cellular cholesterol distribution and homeostasis.
Collapse
Affiliation(s)
- Tomoki Naito
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, 308232, Singapore
| | - Haoning Yang
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, 308232, Singapore
| | - Dylan Hong Zheng Koh
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, 308232, Singapore
| | - Divyanshu Mahajan
- School of Biological Sciences, Nanyang Technological University, Singapore, 637551, Singapore
| | - Lei Lu
- School of Biological Sciences, Nanyang Technological University, Singapore, 637551, Singapore
| | - Yasunori Saheki
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, 308232, Singapore.
- Institute of Resource Development and Analysis, Kumamoto University, Kumamoto, 860-0811, Japan.
| |
Collapse
|
10
|
Liu X, Jiang L, Ke M, Sigal IA, Chua J, Hoang QV, Chia AW, Najjar RP, Tan B, Cheong J, Bellemo V, Chong RS, Girard MJA, Ang M, Liu M, Garhöfer G, Barathi VA, Saw SM, Villiger M, Schmetterer L. Posterior scleral birefringence measured by triple-input polarization-sensitive imaging as a biomarker of myopia progression. Nat Biomed Eng 2023; 7:986-1000. [PMID: 37365268 PMCID: PMC10427432 DOI: 10.1038/s41551-023-01062-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 05/30/2023] [Indexed: 06/28/2023]
Abstract
In myopic eyes, pathological remodelling of collagen in the posterior sclera has mostly been observed ex vivo. Here we report the development of triple-input polarization-sensitive optical coherence tomography (OCT) for measuring posterior scleral birefringence. In guinea pigs and humans, the technique offers superior imaging sensitivities and accuracies than dual-input polarization-sensitive OCT. In 8-week-long studies with young guinea pigs, scleral birefringence was positively correlated with spherical equivalent refractive errors and predicted the onset of myopia. In a cross-sectional study involving adult individuals, scleral birefringence was associated with myopia status and negatively correlated with refractive errors. Triple-input polarization-sensitive OCT may help establish posterior scleral birefringence as a non-invasive biomarker for assessing the progression of myopia.
Collapse
Affiliation(s)
- Xinyu Liu
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE) programme, Singapore, Singapore
| | - Liqin Jiang
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
| | - Mengyuan Ke
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Ian A Sigal
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Jacqueline Chua
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE) programme, Singapore, Singapore
| | - Quan V Hoang
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine National University of Singapore, Singapore, Singapore
- Department of Ophthalmology, Columbia University, New York, NY, USA
| | - Audrey Wi Chia
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
| | - Raymond P Najjar
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine National University of Singapore, Singapore, Singapore
| | - Bingyao Tan
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE) programme, Singapore, Singapore
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore, Singapore
| | - Jocelyn Cheong
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
| | - Valentina Bellemo
- SERI-NTU Advanced Ocular Engineering (STANCE) programme, Singapore, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Rachel S Chong
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
| | - Michaël J A Girard
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
- Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland
| | - Marcus Ang
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
| | - Mengyang Liu
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Veluchamy A Barathi
- Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine National University of Singapore, Singapore, Singapore
- Translational Pre-Clinical Model Platform, Singapore Eye Research Institute, Singapore, Singapore
| | - Seang-Mei Saw
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
- Saw Swee Hock School of Public Health, ,National University of Singapore, National University Health System, Singapore, Singapore
| | - Martin Villiger
- Wellman Center for Photomedicine, Harvard Medical School and Massachusetts General Hospital, Boston, MA, USA
| | - Leopold Schmetterer
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.
- Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore.
- SERI-NTU Advanced Ocular Engineering (STANCE) programme, Singapore, Singapore.
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore, Singapore.
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore.
- Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland.
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria.
| |
Collapse
|
11
|
Xu H, Huo Y, Zhou Q, Wang LA, Cai P, Doss B, Huang C, Hsia KJ. Geometry-mediated bridging drives nonadhesive stripe wound healing. Proc Natl Acad Sci U S A 2023; 120:e2221040120. [PMID: 37098071 PMCID: PMC10161107 DOI: 10.1073/pnas.2221040120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 03/14/2023] [Indexed: 04/26/2023] Open
Abstract
Wound healing through reepithelialization of gaps is of profound importance to the medical community. One critical mechanism identified by researchers for closing non-cell-adhesive gaps is the accumulation of actin cables around concave edges and the resulting purse-string constriction. However, the studies to date have not separated the gap-edge curvature effect from the gap size effect. Here, we fabricate micropatterned hydrogel substrates with long, straight, and wavy non-cell-adhesive stripes of different gap widths to investigate the stripe edge curvature and stripe width effects on the reepithelialization of Madin-Darby canine kidney (MDCK) cells. Our results show that MDCK cell reepithelization is closely regulated by the gap geometry and may occur through different pathways. In addition to purse-string contraction, we identify gap bridging either via cell protrusion or by lamellipodium extension as critical cellular and molecular mechanisms for wavy gap closure. Cell migration in the direction perpendicular to wound front, sufficiently small gap size to allow bridging, and sufficiently high negative curvature at cell bridges for actin cable constriction are necessary/sufficient conditions for gap closure. Our experiments demonstrate that straight stripes rarely induce cell migration perpendicular to wound front, but wavy stripes do; cell protrusion and lamellipodia extension can help establish bridges over gaps of about five times the cell size, but not significantly beyond. Such discoveries deepen our understanding of mechanobiology of cell responses to curvature and help guide development of biophysical strategies for tissue repair, plastic surgery, and better wound management.
Collapse
Affiliation(s)
- Hongmei Xu
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore639798, Singapore
| | - Yucheng Huo
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore639798, Singapore
| | - Quan Zhou
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore639798, Singapore
| | - Lianghao Abraham Wang
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore639798, Singapore
| | - Pingqiang Cai
- Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, Nanjing211166, PR China
| | - Bryant Doss
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore639798, Singapore
| | - Changjin Huang
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore639798, Singapore
| | - K. Jimmy Hsia
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore639798, Singapore
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore639798, Singapore
| |
Collapse
|
12
|
Cai R, Wadgaonkar I, Lim JWM, Dal Forno S, Giovanni D, Feng M, Ye S, Battiato M, Sum TC. Zero-field quantum beats and spin decoherence mechanisms in CsPbBr 3 perovskite nanocrystals. Nat Commun 2023; 14:2472. [PMID: 37120626 PMCID: PMC10148794 DOI: 10.1038/s41467-023-37721-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 03/24/2023] [Indexed: 05/01/2023] Open
Abstract
Coherent optical manipulation of exciton states provides a fascinating approach for quantum gating and ultrafast switching. However, their coherence time for incumbent semiconductors is highly susceptible to thermal decoherence and inhomogeneous broadening effects. Here, we uncover zero-field exciton quantum beating and anomalous temperature dependence of the exciton spin lifetimes in CsPbBr3 perovskite nanocrystals (NCs) ensembles. The quantum beating between two exciton fine-structure splitting (FSS) levels enables coherent ultrafast optical control of the excitonic degree of freedom. From the anomalous temperature dependence, we identify and fully parametrize all the regimes of exciton spin depolarization, finding that approaching room temperature, it is dominated by a motional narrowing process governed by the exciton multilevel coherence. Importantly, our results present an unambiguous full physical picture of the complex interplay of the underlying spin decoherence mechanisms. These intrinsic exciton FSS states in perovskite NCs present fresh opportunities for spin-based photonic quantum technologies.
Collapse
Affiliation(s)
- Rui Cai
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, Singapore
| | - Indrajit Wadgaonkar
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, Singapore
| | - Jia Wei Melvin Lim
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, Singapore
- ERI@N, Interdisciplinary Graduate School, Nanyang Technological University, Singapore, Singapore
| | - Stefano Dal Forno
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, Singapore
| | - David Giovanni
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, Singapore
| | - Minjun Feng
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, Singapore
| | - Senyun Ye
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, Singapore
| | - Marco Battiato
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, Singapore.
| | - Tze Chien Sum
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, Singapore.
| |
Collapse
|
13
|
Kusuma FK, Prabhu A, Tieo G, Ahmed SM, Dakle P, Yong WK, Pathak E, Madan V, Jiang YY, Tam WL, Kappei D, Dröge P, Koeffler HP, Jeitany M. Signalling inhibition by ponatinib disrupts productive alternative lengthening of telomeres (ALT). Nat Commun 2023; 14:1919. [PMID: 37024489 PMCID: PMC10079688 DOI: 10.1038/s41467-023-37633-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 03/24/2023] [Indexed: 04/08/2023] Open
Abstract
Alternative lengthening of telomeres (ALT) supports telomere maintenance in 10-15% of cancers, thus representing a compelling target for therapy. By performing anti-cancer compound library screen on isogenic cell lines and using extrachromosomal telomeric C-circles, as a bona fide marker of ALT activity, we identify a receptor tyrosine kinase inhibitor ponatinib that deregulates ALT mechanisms, induces telomeric dysfunction, reduced ALT-associated telomere synthesis, and targets, in vivo, ALT-positive cells. Using RNA-sequencing and quantitative phosphoproteomic analyses, combined with C-circle level assessment, we find an ABL1-JNK-JUN signalling circuit to be inhibited by ponatinib and to have a role in suppressing telomeric C-circles. Furthermore, transcriptome and interactome analyses suggest a role of JUN in DNA damage repair. These results are corroborated by synergistic drug interactions between ponatinib and either DNA synthesis or repair inhibitors, such as triciribine. Taken together, we describe here a signalling pathway impacting ALT which can be targeted by a clinically approved drug.
Collapse
Affiliation(s)
- Frances Karla Kusuma
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Aishvaryaa Prabhu
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
| | - Galen Tieo
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Syed Moiz Ahmed
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Pushkar Dakle
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
| | - Wai Khang Yong
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Elina Pathak
- Genome Institute of Singapore, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Vikas Madan
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
| | - Yan Yi Jiang
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
- Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, P. R. China
| | - Wai Leong Tam
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- Genome Institute of Singapore, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Dennis Kappei
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- NUS Center for Cancer Research, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Peter Dröge
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - H Phillip Koeffler
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
- Cedars-Sinai Medical Center, Division of Hematology/Oncology, UCLA School of Medicine, Los Angeles, CA, USA
- Department of Hematology-Oncology, National University Cancer Institute of Singapore (NCIS), National University Hospital, Singapore, Singapore
| | - Maya Jeitany
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore.
| |
Collapse
|
14
|
Próchnicki T, Vasconcelos MB, Robinson KS, Mangan MSJ, De Graaf D, Shkarina K, Lovotti M, Standke L, Kaiser R, Stahl R, Duthie FG, Rothe M, Antonova K, Jenster LM, Lau ZH, Rösing S, Mirza N, Gottschild C, Wachten D, Günther C, Kufer TA, Schmidt FI, Zhong FL, Latz E. Mitochondrial damage activates the NLRP10 inflammasome. Nat Immunol 2023; 24:595-603. [PMID: 36941400 DOI: 10.1038/s41590-023-01451-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Accepted: 02/06/2023] [Indexed: 03/23/2023]
Abstract
Upon detecting pathogens or cell stress, several NOD-like receptors (NLRs) form inflammasome complexes with the adapter ASC and caspase-1, inducing gasdermin D (GSDMD)-dependent cell death and maturation and release of IL-1β and IL-18. The triggers and activation mechanisms of several inflammasome-forming sensors are not well understood. Here we show that mitochondrial damage activates the NLRP10 inflammasome, leading to ASC speck formation and caspase-1-dependent cytokine release. While the AIM2 inflammasome can also sense mitochondrial demise by detecting mitochondrial DNA (mtDNA) in the cytosol, NLRP10 monitors mitochondrial integrity in an mtDNA-independent manner, suggesting the recognition of distinct molecular entities displayed by the damaged organelles. NLRP10 is highly expressed in differentiated human keratinocytes, in which it can also assemble an inflammasome. Our study shows that this inflammasome surveils mitochondrial integrity. These findings might also lead to a better understanding of mitochondria-linked inflammatory diseases.
Collapse
Affiliation(s)
- Tomasz Próchnicki
- Institute of Innate Immunity, Medical Faculty, University of Bonn, Bonn, Germany
| | | | - Kim S Robinson
- A*STAR Skin Research Labs (A*SRL), Clinical Sciences Building, Singapore, Singapore
- Skin Research Institute of Singapore (SRIS), Clinical Sciences Building, Singapore, Singapore
| | - Matthew S J Mangan
- Institute of Innate Immunity, Medical Faculty, University of Bonn, Bonn, Germany
| | - Dennis De Graaf
- Institute of Innate Immunity, Medical Faculty, University of Bonn, Bonn, Germany
| | - Kateryna Shkarina
- Institute of Innate Immunity, Medical Faculty, University of Bonn, Bonn, Germany
| | - Marta Lovotti
- Institute of Innate Immunity, Medical Faculty, University of Bonn, Bonn, Germany
| | - Lena Standke
- Institute of Innate Immunity, Medical Faculty, University of Bonn, Bonn, Germany
| | - Romina Kaiser
- Institute of Innate Immunity, Medical Faculty, University of Bonn, Bonn, Germany
| | - Rainer Stahl
- Institute of Innate Immunity, Medical Faculty, University of Bonn, Bonn, Germany
| | - Fraser G Duthie
- Institute of Innate Immunity, Medical Faculty, University of Bonn, Bonn, Germany
| | - Maximilian Rothe
- Institute of Innate Immunity, Medical Faculty, University of Bonn, Bonn, Germany
| | - Kateryna Antonova
- Institute of Innate Immunity, Medical Faculty, University of Bonn, Bonn, Germany
| | - Lea-Marie Jenster
- Institute of Innate Immunity, Medical Faculty, University of Bonn, Bonn, Germany
| | - Zhi Heng Lau
- A*STAR Skin Research Labs (A*SRL), Clinical Sciences Building, Singapore, Singapore
- Skin Research Institute of Singapore (SRIS), Clinical Sciences Building, Singapore, Singapore
| | - Sarah Rösing
- Department of Dermatology, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Nora Mirza
- Institute of Nutritional Medicine, Department of Immunology, University of Hohenheim, Stuttgart, Stuttgart, Germany
| | - Clarissa Gottschild
- Institute of Nutritional Medicine, Department of Immunology, University of Hohenheim, Stuttgart, Stuttgart, Germany
| | - Dagmar Wachten
- Institute of Innate Immunity, Medical Faculty, University of Bonn, Bonn, Germany
| | - Claudia Günther
- Department of Dermatology, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Thomas A Kufer
- Institute of Nutritional Medicine, Department of Immunology, University of Hohenheim, Stuttgart, Stuttgart, Germany
| | - Florian I Schmidt
- Institute of Innate Immunity, Medical Faculty, University of Bonn, Bonn, Germany
| | - Franklin L Zhong
- Skin Research Institute of Singapore (SRIS), Immunos, Singapore, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Eicke Latz
- Institute of Innate Immunity, Medical Faculty, University of Bonn, Bonn, Germany.
- German Center of Neurodegenerative Diseases (DZNE), Bonn, Germany.
- Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, MA, USA.
| |
Collapse
|
15
|
Fairley LH, Lai KO, Wong JH, Chong WJ, Vincent AS, D’Agostino G, Wu X, Naik RR, Jayaraman A, Langley SR, Ruedl C, Barron AM. Mitochondrial control of microglial phagocytosis by the translocator protein and hexokinase 2 in Alzheimer's disease. Proc Natl Acad Sci U S A 2023; 120:e2209177120. [PMID: 36787364 PMCID: PMC9974442 DOI: 10.1073/pnas.2209177120] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 12/17/2022] [Indexed: 02/15/2023] Open
Abstract
Microglial phagocytosis is an energetically demanding process that plays a critical role in the removal of toxic protein aggregates in Alzheimer's disease (AD). Recent evidence indicates that a switch in energy production from mitochondrial respiration to glycolysis disrupts this important protective microglial function and may provide therapeutic targets for AD. Here, we demonstrate that the translocator protein (TSPO) and a member of its mitochondrial complex, hexokinase-2 (HK), play critical roles in microglial respiratory-glycolytic metabolism and phagocytosis. Pharmacological and genetic loss-of-function experiments showed that TSPO is critical for microglial respiratory metabolism and energy supply for phagocytosis, and its expression is enriched in phagocytic microglia of AD mice. Meanwhile, HK controlled glycolytic metabolism and phagocytosis via mitochondrial binding or displacement. In cultured microglia, TSPO deletion impaired mitochondrial respiration and increased mitochondrial recruitment of HK, inducing a switch to glycolysis and reducing phagocytosis. To determine the functional significance of mitochondrial HK recruitment, we developed an optogenetic tool for reversible control of HK localization. Displacement of mitochondrial HK inhibited glycolysis and improved phagocytosis in TSPO-knockout microglia. Mitochondrial HK recruitment also coordinated the inflammatory switch to glycolysis that occurs in response to lipopolysaccharide in normal microglia. Interestingly, cytosolic HK increased phagocytosis independent of its metabolic activity, indicating an immune signaling function. Alzheimer's beta amyloid drastically stimulated mitochondrial HK recruitment in cultured microglia, which may contribute to microglial dysfunction in AD. Thus, targeting mitochondrial HK may offer an immunotherapeutic approach to promote phagocytic microglial function in AD.
Collapse
Affiliation(s)
- Lauren H. Fairley
- Neurobiology of Aging and Disease Laboratory, Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, 308232, Singapore
| | - Kei Onn Lai
- Neurobiology of Aging and Disease Laboratory, Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, 308232, Singapore
| | - Jia Hui Wong
- Neurobiology of Aging and Disease Laboratory, Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, 308232, Singapore
| | - Wei Jing Chong
- Neurobiology of Aging and Disease Laboratory, Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, 308232, Singapore
| | - Anselm Salvatore Vincent
- Neurobiology of Aging and Disease Laboratory, Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, 308232, Singapore
| | - Giuseppe D’Agostino
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, 308232, Singapore
| | - Xiaoting Wu
- School of Biological Sciences, Nanyang Technological University Singapore, 637551, Singapore
| | - Roshan R. Naik
- Neurobiology of Aging and Disease Laboratory, Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, 308232, Singapore
| | - Anusha Jayaraman
- Center for Molecular Neuropathology, Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, 308232, Singapore
| | - Sarah R. Langley
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, 308232, Singapore
| | - Christiane Ruedl
- School of Biological Sciences, Nanyang Technological University Singapore, 637551, Singapore
| | - Anna M. Barron
- Neurobiology of Aging and Disease Laboratory, Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, 308232, Singapore
| |
Collapse
|
16
|
Qiang Y, Sissoko A, Liu ZL, Dong T, Zheng F, Kong F, Higgins JM, Karniadakis GE, Buffet PA, Suresh S, Dao M. Microfluidic study of retention and elimination of abnormal red blood cells by human spleen with implications for sickle cell disease. Proc Natl Acad Sci U S A 2023; 120:e2217607120. [PMID: 36730189 PMCID: PMC9963977 DOI: 10.1073/pnas.2217607120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 12/16/2022] [Indexed: 02/03/2023] Open
Abstract
The spleen clears altered red blood cells (RBCs) from circulation, contributing to the balance between RBC formation (erythropoiesis) and removal. The splenic RBC retention and elimination occur predominantly in open circulation where RBCs flow through macrophages and inter-endothelial slits (IESs). The mechanisms underlying and interconnecting these processes significantly impact clinical outcomes. In sickle cell disease (SCD), blockage of intrasplenic sickled RBCs is observed in infants splenectomized due to acute splenic sequestration crisis (ASSC). This life-threatening RBC pooling and organ swelling event is plausibly triggered or enhanced by intra-tissular hypoxia. We present an oxygen-mediated spleen-on-a-chip platform for in vitro investigations of the homeostatic balance in the spleen. To demonstrate and validate the benefits of this general microfluidic platform, we focus on SCD and study the effects of hypoxia on splenic RBC retention and elimination. We observe that RBC retention by IESs and RBC-macrophage adhesion are faster in blood samples from SCD patients than those from healthy subjects. This difference is markedly exacerbated under hypoxia. Moreover, the sickled RBCs under hypoxia show distinctly different phagocytosis processes from those non-sickled RBCs under hypoxia or normoxia. We find that reoxygenation significantly alleviates RBC retention at IESs, and leads to rapid unsickling and fragmentation of the ingested sickled RBCs inside macrophages. These results provide unique mechanistic insights into how the spleen maintains its homeostatic balance between splenic RBC retention and elimination, and shed light on how disruptions in this balance could lead to anemia, splenomegaly, and ASSC in SCD and possible clinical manifestations in other hematologic diseases.
Collapse
Affiliation(s)
- Yuhao Qiang
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA02139
| | - Abdoulaye Sissoko
- Université Paris Cité, INSERM, Biologie Intégrée du Globule Rouge,75015Paris, France
- Université des Antilles, Biologie Intégrée du Globule Rouge,75015Paris, France
- Laboratoire d'Excellence du Globule Rouge,75015Paris, France
| | - Zixiang L. Liu
- Division of Applied Mathematics, Brown University, Providence, RI02912
| | - Ting Dong
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA02139
| | - Fuyin Zheng
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA02139
- School of Biological Sciences, Nanyang Technological University,639798Singapore, Singapore
| | - Fang Kong
- School of Biological Sciences, Nanyang Technological University,639798Singapore, Singapore
| | - John M. Higgins
- Massachusetts General Hospital, Harvard Medical School, Boston, MA02114
| | | | - Pierre A. Buffet
- Université Paris Cité, INSERM, Biologie Intégrée du Globule Rouge,75015Paris, France
- Université des Antilles, Biologie Intégrée du Globule Rouge,75015Paris, France
- Laboratoire d'Excellence du Globule Rouge,75015Paris, France
| | - Subra Suresh
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA02139
- Nanyang Technological University,639798Singapore, Singapore
| | - Ming Dao
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA02139
- School of Biological Sciences, Nanyang Technological University,639798Singapore, Singapore
| |
Collapse
|
17
|
Makino H. Arithmetic value representation for hierarchical behavior composition. Nat Neurosci 2023; 26:140-149. [PMID: 36550292 PMCID: PMC9829535 DOI: 10.1038/s41593-022-01211-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Accepted: 10/21/2022] [Indexed: 12/24/2022]
Abstract
The ability to compose new skills from a preacquired behavior repertoire is a hallmark of biological intelligence. Although artificial agents extract reusable skills from past experience and recombine them in a hierarchical manner, whether the brain similarly composes a novel behavior is largely unknown. In the present study, I show that deep reinforcement learning agents learn to solve a novel composite task by additively combining representations of prelearned action values of constituent subtasks. Learning efficacy in the composite task was further augmented by the introduction of stochasticity in behavior during pretraining. These theoretical predictions were empirically tested in mice, where subtask pretraining enhanced learning of the composite task. Cortex-wide, two-photon calcium imaging revealed analogous neural representations of combined action values, with improved learning when the behavior variability was amplified. Together, these results suggest that the brain composes a novel behavior with a simple arithmetic operation of preacquired action-value representations with stochastic policies.
Collapse
Affiliation(s)
- Hiroshi Makino
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore.
| |
Collapse
|
18
|
Ma Z, Sun Y, Zhu X, Yang L, Chen X, Miao Y. Membrane nanodomains modulate formin condensation for actin remodeling in Arabidopsis innate immune responses. Plant Cell 2022; 34:374-394. [PMID: 34726756 PMCID: PMC8774048 DOI: 10.1093/plcell/koab261] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 10/20/2021] [Indexed: 05/23/2023]
Abstract
The assembly of macromolecules on the plasma membrane concentrates cell surface biomolecules into nanometer- to micrometer-scale clusters (nano- or microdomains) that help the cell initiate or respond to signals. In plant-microbe interactions, the actin cytoskeleton undergoes rapid remodeling during pathogen-associated molecular pattern-triggered immunity (PTI). The nanoclustering of formin-actin nucleator proteins at the cell surface has been identified as underlying actin nucleation during plant innate immune responses. Here, we show that the condensation of nanodomain constituents and the self-assembly of remorin proteins enables this mechanism of controlling formin condensation and activity during innate immunity in Arabidopsis thaliana. Through intrinsically disordered region-mediated remorin oligomerization and formin interaction, remorin gradually recruits and condenses formins upon PTI activation in lipid bilayers, consequently increasing actin nucleation in a time-dependent manner postinfection. Such nanodomain- and remorin-mediated regulation of plant surface biomolecules is expected to be a general feature of plant innate immune responses that creates spatially separated biochemical compartments and fine tunes membrane physicochemical properties for transduction of immune signals in the host.
Collapse
Affiliation(s)
- Zhiming Ma
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
| | - Yanbiao Sun
- Haixia Institute of Science and Technology, Horticultural Plant Biology and Metabolomics Centre, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Xinlu Zhu
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
| | - Liang Yang
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore 637551, Singapore
- School of Medicine, Southern University of Science and Technology, 1088 Xueyuan Blvd, Nanshan District, Shenzhen, 518055, China
| | - Xu Chen
- Haixia Institute of Science and Technology, Horticultural Plant Biology and Metabolomics Centre, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | | |
Collapse
|
19
|
Ho AHY, Tan-Ho G, Ngo TA, Ong G, Chong PH, Dignadice D, Potash J. A Novel Mindful-Compassion Art-Based Therapy for Reducing Burnout and Promoting Resilience Among Healthcare Workers: Findings From a Waitlist Randomized Control Trial. Front Psychol 2021; 12:744443. [PMID: 34744918 PMCID: PMC8566679 DOI: 10.3389/fpsyg.2021.744443] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 09/08/2021] [Indexed: 11/28/2022] Open
Abstract
Protecting the mental health of healthcare workers is an urgent global public health priority. Healthcare workers, especially those immersed in palliative care, are prone to burnout due to the intense emotions associated with end-of-life caregiving. This study examines the efficacy of a novel, multimodal, and group-based Mindful-Compassion Art-based Therapy (MCAT) that integrates reflective self-awareness with creative emotional expression for protecting healthcare workers' mental health. A dual-arm open-label waitlist randomized controlled trial was conducted. A total of 56 healthcare workers were recruited from the largest homecare hospice in Singapore and randomized to the immediate-treatment condition of a standardized 6-week, 18-hours MCAT intervention (n=29), or the waitlist-control condition (n=27). Self-administered outcome measures on burnout, resilience, emotional regulation, self-compassion, death attitudes, and quality of life were collected at baseline, post-intervention/second-baseline at 6weeks, and follow-up/post-intervention at 12weeks. Results from mixed model ANOVAs reveal that treatment group participants experienced significant reduction in mental exhaustion, as well as significant improvements in overall emotional regulation, nonreactivity to intrusive thoughts, approach acceptance of death, and afterlife belief as compared to waitlist-control immediately after MCAT completion. Effect sizes of these impacts ranged from medium to large (η 2=0.65 to 0.170). Results from one-way ANOVAs further reveal that the treatment gains of reduced mental exhaustion and increased emotional regulation were maintained among treatment group participants at 12-weeks follow-up compared to baseline, with new benefits identified. These include increased ability to observe and describe one's experiences, elevated overall self-compassion, greater mindful awareness, enhanced common humanity, and better quality of life. Effect sizes of these impacts were large (η 2=0.128 to 0.298). These findings reflect the robust effectiveness and positive residual effects of MCAT for reducing burnout, building resilience, nurturing compassion, fostering collegial support, and promoting mental wellness among healthcare workers. The clinical model and applicability of MCAT in larger and more diverse caregiving contexts, such as family dementia care, are discussed. Clinical Trial Registration: ClinicalTrials.gov # NCT03440606, #NCT04548089.
Collapse
Affiliation(s)
- Andy Hau Yan Ho
- Action Research for Community Health Laboratory, Psychology Programme, School of Social Sciences, Nanyang Technological University, Singapore, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
- The Palliative Care Centre for Excellence in Research and Education, Singapore, Singapore
| | - Geraldine Tan-Ho
- Action Research for Community Health Laboratory, Psychology Programme, School of Social Sciences, Nanyang Technological University, Singapore, Singapore
| | - Thuy Anh Ngo
- Action Research for Community Health Laboratory, Psychology Programme, School of Social Sciences, Nanyang Technological University, Singapore, Singapore
| | - Grace Ong
- Assisi Hospice, Singapore, Singapore
| | | | | | - Jordan Potash
- Art Therapy Program, The George Washington University, Ashburn, VA, United States
| |
Collapse
|
20
|
Jeyasimman D, Ercan B, Dharmawan D, Naito T, Sun J, Saheki Y. PDZD-8 and TEX-2 regulate endosomal PI(4,5)P 2 homeostasis via lipid transport to promote embryogenesis in C. elegans. Nat Commun 2021; 12:6065. [PMID: 34663803 PMCID: PMC8523718 DOI: 10.1038/s41467-021-26177-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 09/22/2021] [Indexed: 11/10/2022] Open
Abstract
Different types of cellular membranes have unique lipid compositions that are important for their functional identity. PI(4,5)P2 is enriched in the plasma membrane where it contributes to local activation of key cellular events, including actomyosin contraction and cytokinesis. However, how cells prevent PI(4,5)P2 from accumulating in intracellular membrane compartments, despite constant intermixing and exchange of lipid membranes, is poorly understood. Using the C. elegans early embryo as our model system, we show that the evolutionarily conserved lipid transfer proteins, PDZD-8 and TEX-2, act together with the PI(4,5)P2 phosphatases, OCRL-1 and UNC-26/synaptojanin, to prevent the build-up of PI(4,5)P2 on endosomal membranes. In the absence of these four proteins, large amounts of PI(4,5)P2 accumulate on endosomes, leading to embryonic lethality due to ectopic recruitment of proteins involved in actomyosin contractility. PDZD-8 localizes to the endoplasmic reticulum and regulates endosomal PI(4,5)P2 levels via its lipid harboring SMP domain. Accumulation of PI(4,5)P2 on endosomes is accompanied by impairment of their degradative capacity. Thus, cells use multiple redundant systems to maintain endosomal PI(4,5)P2 homeostasis.
Collapse
Affiliation(s)
- Darshini Jeyasimman
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, 308232, Singapore
| | - Bilge Ercan
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, 308232, Singapore
| | - Dennis Dharmawan
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, 308232, Singapore
| | - Tomoki Naito
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, 308232, Singapore
| | - Jingbo Sun
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, 308232, Singapore
| | - Yasunori Saheki
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, 308232, Singapore.
- Department of Molecular Physiology, Faculty of Life Sciences, Kumamoto University, Kumamoto, 860-8556, Japan.
| |
Collapse
|
21
|
Yong T, Báti G, García F, Stuparu MC. Mechanochemical transformation of planar polyarenes to curved fused-ring systems. Nat Commun 2021; 12:5187. [PMID: 34465777 PMCID: PMC8408202 DOI: 10.1038/s41467-021-25495-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 08/04/2021] [Indexed: 11/29/2022] Open
Abstract
The transformation of planar aromatic molecules into π-extended non-planar structures is a challenging task and has not been realized by mechanochemistry before. Here we report that mechanochemical forces can successfully transform a planar polyarene into a curved geometry by creating new C-C bonds along the rim of the molecular structure. In doing so, mechanochemistry does not require inert conditions or organic solvents and provide better yields within shorter reaction times. This is illustrated in a 20-minute synthesis of corannulene, a fragment of fullerene C60, in 66% yield through ball milling of planar tetrabromomethylfluoranthene precursor under ambient conditions. Traditional solution and gas-phase synthetic pathways do not compete with the practicality and efficiency offered by the mechanochemical synthesis, which now opens up a new reaction space for inducing curvature at a molecular level.
Collapse
Affiliation(s)
- Teoh Yong
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, Singapore
| | - Gábor Báti
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, Singapore
| | - Felipe García
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, Singapore.
| | - Mihaiela C Stuparu
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, Singapore.
| |
Collapse
|
22
|
Sun H, Zhu X, Li C, Ma Z, Han X, Luo Y, Yang L, Yu J, Miao Y. Xanthomonas effector XopR hijacks host actin cytoskeleton via complex coacervation. Nat Commun 2021; 12:4064. [PMID: 34210966 PMCID: PMC8249405 DOI: 10.1038/s41467-021-24375-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 06/11/2021] [Indexed: 01/09/2023] Open
Abstract
The intrinsically disordered region (IDR) is a preserved signature of phytobacterial type III effectors (T3Es). The T3E IDR is thought to mediate unfolding during translocation into the host cell and to avoid host defense by sequence diversification. Here, we demonstrate a mechanism of host subversion via the T3E IDR. We report that the Xanthomonas campestris T3E XopR undergoes liquid-liquid phase separation (LLPS) via multivalent IDR-mediated interactions that hijack the Arabidopsis actin cytoskeleton. XopR is gradually translocated into host cells during infection and forms a macromolecular complex with actin-binding proteins at the cell cortex. By tuning the physical-chemical properties of XopR-complex coacervates, XopR progressively manipulates multiple steps of actin assembly, including formin-mediated nucleation, crosslinking of F-actin, and actin depolymerization, which occurs through competition for actin-depolymerizing factor and depends on constituent stoichiometry. Our findings unravel a sophisticated strategy in which bacterial T3E subverts the host actin cytoskeleton via protein complex coacervation.
Collapse
Affiliation(s)
- He Sun
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Xinlu Zhu
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Chuanxi Li
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, Singapore
| | - Zhiming Ma
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Xiao Han
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Yuanyuan Luo
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Liang Yang
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
| | - Jing Yu
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, Singapore
| | - Yansong Miao
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore.
| |
Collapse
|
23
|
John RA, Shah N, Vishwanath SK, Ng SE, Febriansyah B, Jagadeeswararao M, Chang CH, Basu A, Mathews N. Halide perovskite memristors as flexible and reconfigurable physical unclonable functions. Nat Commun 2021; 12:3681. [PMID: 34140514 PMCID: PMC8211866 DOI: 10.1038/s41467-021-24057-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Accepted: 05/27/2021] [Indexed: 11/15/2022] Open
Abstract
Physical Unclonable Functions (PUFs) address the inherent limitations of conventional hardware security solutions in edge-computing devices. Despite impressive demonstrations with silicon circuits and crossbars of oxide memristors, realizing efficient roots of trust for resource-constrained hardware remains a significant challenge. Hybrid organic electronic materials with a rich reservoir of exotic switching physics offer an attractive, inexpensive alternative to design efficient cryptographic hardware, but have not been investigated till date. Here, we report a breakthrough security primitive exploiting the switching physics of one dimensional halide perovskite memristors as excellent sources of entropy for secure key generation and device authentication. Measurements of a prototypical 1 kb propyl pyridinium lead iodide (PrPyr[PbI3]) weak memristor PUF with a differential write-back strategy reveals near ideal uniformity, uniqueness and reliability without additional area and power overheads. Cycle-to-cycle write variability enables reconfigurability, while in-memory computing empowers a strong recurrent PUF construction to thwart machine learning attacks.
Collapse
Affiliation(s)
- Rohit Abraham John
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, Singapore
| | - Nimesh Shah
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore, Singapore
| | - Sujaya Kumar Vishwanath
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, Singapore
| | - Si En Ng
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, Singapore
| | - Benny Febriansyah
- Energy Research Institute @ NTU (ERI@N), Nanyang Technological University, Singapore, Singapore
| | | | - Chip-Hong Chang
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore, Singapore
| | - Arindam Basu
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore, Singapore.
| | - Nripan Mathews
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, Singapore.
- Energy Research Institute @ NTU (ERI@N), Nanyang Technological University, Singapore, Singapore.
| |
Collapse
|
24
|
Giovanni D, Righetto M, Zhang Q, Lim JWM, Ramesh S, Sum TC. Origins of the long-range exciton diffusion in perovskite nanocrystal films: photon recycling vs exciton hopping. Light Sci Appl 2021; 10:2. [PMID: 33386385 PMCID: PMC7775951 DOI: 10.1038/s41377-020-00443-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Revised: 11/13/2020] [Accepted: 11/23/2020] [Indexed: 05/03/2023]
Abstract
The outstanding optoelectronic performance of lead halide perovskites lies in their exceptional carrier diffusion properties. As the perovskite material dimensionality is reduced to exploit the quantum confinement effects, the disruption to the perovskite lattice, often with insulating organic ligands, raises new questions on the charge diffusion properties. Herein, we report direct imaging of >1 μm exciton diffusion lengths in CH3NH3PbBr3 perovskite nanocrystal (PNC) films. Surprisingly, the resulting exciton mobilities in these PNC films can reach 10 ± 2 cm2 V-1 s-1, which is counterintuitively several times higher than the carrier mobility in 3D perovskite films. We show that this ultralong exciton diffusion originates from both efficient inter-NC exciton hopping (via Förster energy transfer) and the photon recycling process with a smaller yet significant contribution. Importantly, our study not only sheds new light on the highly debated origins of the excellent exciton diffusion in PNC films but also highlights the potential of PNCs for optoelectronic applications.
Collapse
Affiliation(s)
- David Giovanni
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University (NTU), 21 Nanyang Link, Singapore, 637371, Singapore
| | - Marcello Righetto
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University (NTU), 21 Nanyang Link, Singapore, 637371, Singapore
| | - Qiannan Zhang
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University (NTU), 21 Nanyang Link, Singapore, 637371, Singapore
| | - Jia Wei Melvin Lim
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University (NTU), 21 Nanyang Link, Singapore, 637371, Singapore
- Energy Research Institute @NTU (ERI@N), Interdisciplinary Graduate School, Nanyang Technological University, 50 Nanyang Avenue, S2-B3a-01, Singapore, 639798, Singapore
| | - Sankaran Ramesh
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University (NTU), 21 Nanyang Link, Singapore, 637371, Singapore
- Energy Research Institute @NTU (ERI@N), Interdisciplinary Graduate School, Nanyang Technological University, 50 Nanyang Avenue, S2-B3a-01, Singapore, 639798, Singapore
| | - Tze Chien Sum
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University (NTU), 21 Nanyang Link, Singapore, 637371, Singapore.
| |
Collapse
|
25
|
Ye F, Wang C, Fu Q, Yan XF, Bharath SR, Casanas A, Wang M, Song H, Zhang LH, Gao YG. Structural basis of a novel repressor, SghR, controlling Agrobacterium infection by cross-talking to plants. J Biol Chem 2020; 295:12290-12304. [PMID: 32651231 PMCID: PMC7443487 DOI: 10.1074/jbc.ra120.012908] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 07/03/2020] [Indexed: 11/06/2022] Open
Abstract
Agrobacterium tumefaciens infects various plants and causes crown gall diseases involving temporal expression of virulence factors. SghA is a newly identified virulence factor enzymatically releasing salicylic acid from its glucoside conjugate and controlling plant tumor development. Here, we report the structural basis of SghR, a LacI-type transcription factor highly conserved in Rhizobiaceae family, regulating the expression of SghA and involved in tumorigenesis. We identified and characterized the binding site of SghR on the promoter region of sghA and then determined the crystal structures of apo-SghR, SghR complexed with its operator DNA, and ligand sucrose, respectively. These results provide detailed insights into how SghR recognizes its cognate DNA and shed a mechanistic light on how sucrose attenuates the affinity of SghR with DNA to modulate the expression of SghA. Given the important role of SghR in mediating the signaling cross-talk during Agrobacterium infection, our results pave the way for structure-based inducer analog design, which has potential applications for agricultural industry.
Collapse
Affiliation(s)
- Fuzhou Ye
- School of Biological Sciences, Nanyang Technological University, Singapore
| | - Chao Wang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
| | - Qinqin Fu
- School of Biological Sciences, Nanyang Technological University, Singapore
| | - Xin-Fu Yan
- School of Biological Sciences, Nanyang Technological University, Singapore
| | | | - Arnau Casanas
- Swiss Light Source at Paul Scherrer Institut, Villigen, Switzerland
| | - Meitian Wang
- Swiss Light Source at Paul Scherrer Institut, Villigen, Switzerland
| | - Haiwei Song
- Institute of Molecular and Cell Biology, Singapore
| | - Lian-Hui Zhang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
- Institute of Molecular and Cell Biology, Singapore
| | - Yong-Gui Gao
- School of Biological Sciences, Nanyang Technological University, Singapore
- Institute of Molecular and Cell Biology, Singapore
| |
Collapse
|
26
|
Gabryelczyk B, Cai H, Shi X, Sun Y, Swinkels PJM, Salentinig S, Pervushin K, Miserez A. Hydrogen bond guidance and aromatic stacking drive liquid-liquid phase separation of intrinsically disordered histidine-rich peptides. Nat Commun 2019; 10:5465. [PMID: 31784535 PMCID: PMC6884462 DOI: 10.1038/s41467-019-13469-8] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 11/07/2019] [Indexed: 01/07/2023] Open
Abstract
Liquid-liquid phase separation (LLPS) of intrinsically disordered proteins (IDPs) is involved in both intracellular membraneless organelles and extracellular tissues. Despite growing understanding of LLPS, molecular-level mechanisms behind this process are still not fully established. Here, we use histidine-rich squid beak proteins (HBPs) as model IDPs to shed light on molecular interactions governing LLPS. We show that LLPS of HBPs is mediated though specific modular repeats. The morphology of separated phases (liquid-like versus hydrogels) correlates with the repeats' hydrophobicity. Solution-state NMR indicates that LLPS is a multistep process initiated by deprotonation of histidine residues, followed by transient hydrogen bonding with tyrosine, and eventually by hydrophobic interactions. The microdroplets are stabilized by aromatic clustering of tyrosine residues exhibiting restricted molecular mobility in the nano-to-microsecond timescale according to solid-state NMR experiments. Our findings provide guidelines to rationally design pH-responsive peptides with LLPS ability for various applications, including bioinspired protocells and smart drug-delivery systems.
Collapse
Affiliation(s)
- Bartosz Gabryelczyk
- Center for Biomimetic Sensor Science, School of Materials Science and Engineering, Nanyang Technological University (NTU), 50 Nanyang Drive, Singapore, 637553, Singapore
- Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, Kemistintie 1, 02150, Espoo, Finland
| | - Hao Cai
- Center for Biomimetic Sensor Science, School of Materials Science and Engineering, Nanyang Technological University (NTU), 50 Nanyang Drive, Singapore, 637553, Singapore
| | - Xiangyan Shi
- School of Physical and Mathematical Sciences, NTU, 21 Nanyang Link, Singapore, 637371, Singapore
| | - Yue Sun
- Center for Biomimetic Sensor Science, School of Materials Science and Engineering, Nanyang Technological University (NTU), 50 Nanyang Drive, Singapore, 637553, Singapore
| | - Piet J M Swinkels
- Center for Biomimetic Sensor Science, School of Materials Science and Engineering, Nanyang Technological University (NTU), 50 Nanyang Drive, Singapore, 637553, Singapore
- Physical Chemistry and Soft Matter, Wageningen University, 6708 WE, Wageningen, Netherlands
| | - Stefan Salentinig
- Laboratory for Biointerfaces, Department Materials Meet Life, EMPA, CH-9014, St-Gallen, Switzerland
- Department of Chemistry, University of Fribourg, Chemin du Musée 9, 1700, Fribourg, Switzerland
| | - Konstantin Pervushin
- School of Biological Sciences, NTU, 60 Nanyang Drive, Singapore, 637551, Singapore.
| | - Ali Miserez
- Center for Biomimetic Sensor Science, School of Materials Science and Engineering, Nanyang Technological University (NTU), 50 Nanyang Drive, Singapore, 637553, Singapore.
- School of Biological Sciences, NTU, 60 Nanyang Drive, Singapore, 637551, Singapore.
| |
Collapse
|
27
|
Lim AE, Lim CY, Lam YC, Taboryski R. Electroosmotic Flow in Microchannel with Black Silicon Nanostructures. Micromachines (Basel) 2018; 9:E229. [PMID: 30424162 PMCID: PMC6187698 DOI: 10.3390/mi9050229] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Revised: 05/07/2018] [Accepted: 05/08/2018] [Indexed: 02/01/2023]
Abstract
Although electroosmotic flow (EOF) has been applied to drive fluid flow in microfluidic chips, some of the phenomena associated with it can adversely affect the performance of certain applications such as electrophoresis and ion preconcentration. To minimize the undesirable effects, EOF can be suppressed by polymer coatings or introduction of nanostructures. In this work, we presented a novel technique that employs the Dry Etching, Electroplating and Molding (DEEMO) process along with reactive ion etching (RIE), to fabricate microchannel with black silicon nanostructures (prolate hemispheroid-like structures). The effect of black silicon nanostructures on EOF was examined experimentally by current monitoring method, and numerically by finite element simulations. The experimental results showed that the EOF velocity was reduced by 13 ± 7%, which is reasonably close to the simulation results that predict a reduction of approximately 8%. EOF reduction is caused by the distortion of local electric field at the nanostructured surface. Numerical simulations show that the EOF velocity decreases with increasing nanostructure height or decreasing diameter. This reveals the potential of tuning the etching process parameters to generate nanostructures for better EOF suppression. The outcome of this investigation enhances the fundamental understanding of EOF behavior, with implications on the precise EOF control in devices utilizing nanostructured surfaces for chemical and biological analyses.
Collapse
Affiliation(s)
- An Eng Lim
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore.
| | - Chun Yee Lim
- Engineering Cluster, Singapore Institute of Technology, 10 Dover Drive, Singapore 138682, Singapore.
| | - Yee Cheong Lam
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore.
| | - Rafael Taboryski
- Department of Micro- and Nanotechnology, Technical University of Denmark, 2800 Kongens Lyngby, Denmark.
| |
Collapse
|