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Eckert J, van Loon JJWA, Eng LM, Schmidt T. Hypergravity affects cell traction forces of fibroblasts. Biophys J 2021; 120:773-780. [PMID: 33657362 DOI: 10.1016/j.bpj.2021.01.021] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 12/24/2020] [Accepted: 01/08/2021] [Indexed: 11/18/2022] Open
Abstract
Cells sense and react on changes of the mechanical properties of their environment and, likewise, respond to external mechanical stress applied to them. However, whether the gravitational field as overall body force modulates cellular behavior is unclear. Different studies demonstrated that micro- and hypergravity influences the shape and elasticity of cells, initiate cytoskeleton reorganization, and influence cell motility. All these cellular properties are interconnected and contribute to forces that cells apply on their surrounding microenvironment. Yet, studies that investigated changes of cell traction forces under hypergravity conditions are scarce. Here, we performed hypergravity experiments on 3T3 fibroblast cells using the large-diameter centrifuge at the European Space Agency - European Space Research and Technology Centre. Cells were exposed to hypergravity of up to 19.5 g for 16 h in both the upright and the inverted orientation with respect to the g-force vector. We observed a decrease in cellular traction forces when the gravitational field was increased up to 5.4 g, followed by an increase of traction forces for higher gravity fields up to 19.5 g independent of the orientation of the gravity vector. We attribute the switch in cellular response to shear thinning at low g-forces, followed by significant rearrangement and enforcement of the cytoskeleton at high g-forces.
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Affiliation(s)
- Julia Eckert
- Physics of Life Processes, Leiden Institute of Physics, Leiden University, Leiden, the Netherlands; School of Science, Department of Physics, Technische Universität Dresden, Dresden, Germany; Life & Physical Science, Instrumentation and Life Support Laboratory, ESA/ESTEC, Noordwijk, the Netherlands
| | - Jack J W A van Loon
- Life & Physical Science, Instrumentation and Life Support Laboratory, ESA/ESTEC, Noordwijk, the Netherlands; Dutch Experiment Support Centre, Department of Oral and Maxillofacial Surgery/Oral Pathology, Amsterdam University Medical Centre, location VUmc & Academic Centre for Dentistry Amsterdam, Amsterdam, the Netherlands
| | - Lukas M Eng
- School of Science, Department of Physics, Technische Universität Dresden, Dresden, Germany
| | - Thomas Schmidt
- Physics of Life Processes, Leiden Institute of Physics, Leiden University, Leiden, the Netherlands.
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Bart MC, de Vet SJ, de Bakker DM, Alexander BE, van Oevelen D, van Loon EE, van Loon JJWA, de Goeij JM. Spiculous skeleton formation in the freshwater sponge Ephydatia fluviatilis under hypergravity conditions. PeerJ 2019; 6:e6055. [PMID: 30631642 PMCID: PMC6322483 DOI: 10.7717/peerj.6055] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 10/30/2018] [Indexed: 01/01/2023] Open
Abstract
Successful dispersal of freshwater sponges depends on the formation of dormant sponge bodies (gemmules) under adverse conditions. Gemmule formation allows the sponge to overcome critical environmental conditions, for example, desiccation or freezing, and to re-establish as a fully developed sponge when conditions are more favorable. A key process in sponge development from hatched gemmules is the construction of the silica skeleton. Silica spicules form the structural support for the three-dimensional filtration system the sponge uses to filter food particles from ambient water. We studied the effect of different hypergravity forces (1, 2.5, 5, 10, and 20 × g for 48 h)—as measure for environmental stress—on the ability of developing sponges to set-up their spiculous skeleton. Additionally, we assessed whether the addition of nutrients (i.e., dissolved 13C- and 15N-labeled amino acids) compensates for this stress. Our results show that freshwater sponges can withstand prolonged periods of hypergravity exposure and successfully set-up their skeleton, even after 48 h under 20 × g. Developing sponges were found to take up and assimilate dissolved food before forming a functional filtering system. However, fed and non-fed sponges showed no differences in skeleton formation and relative surface area growth, suggesting that the gemmules’ intrinsic energy fulfills the processes of skeleton construction. Additionally, non-fed sponges formed oscula significantly more often than fed sponges, especially under higher g-forces. This suggests that the eventual formation of a filtration system might be stimulated by food deprivation and environmentally stressful conditions. These findings indicate that the process of spiculous skeleton formation is energy-efficient and highly resilient. The uptake of dissolved food substances by freshwater sponges may contribute to the cycling of dissolved organic matter in freshwater ecosystems where sponges are abundant.
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Affiliation(s)
- Martijn C Bart
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands
| | - Sebastiaan J de Vet
- Earth Surface Science, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands.,Taxonomy & Systematics, Naturalis Biodiversity Center, Leiden, The Netherlands
| | - Didier M de Bakker
- Microbiology & Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research & Utrecht University, Utrecht, The Netherlands
| | - Brittany E Alexander
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands
| | - Dick van Oevelen
- Department of Estuarine and Delta Systems, NIOZ Royal Netherlands Institute for Sea Research & Utrecht University, Utrecht, The Netherlands
| | - E Emiel van Loon
- Department of Computational Geo-Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands
| | - Jack J W A van Loon
- Dutch Experiment Support Center, Department of Oral and Maxillofacial Surgery/Oral Pathology, VU University Medical Center & Academic Centre for Dentistry Amsterdam (ACTA) & European Space Agency Technology Center (ESA-ESTEC), TEC-MMG LIS Lab, Noordwijk, Amsterdam, The Netherlands
| | - Jasper M de Goeij
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands
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Continuous hypergravity alters the cytoplasmic elasticity of MC3T3-E1 osteoblasts via actin filaments. J Biomech 2018. [DOI: 10.1016/j.jbiomech.2018.02.024] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Zhang C, Zhou L, Zhang F, Lü D, Li N, Zheng L, Xu Y, Li Z, Sun S, Long M. Mechanical remodeling of normally sized mammalian cells under a gravity vector. FASEB J 2016; 31:802-813. [PMID: 27871065 DOI: 10.1096/fj.201600897rr] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2016] [Accepted: 10/31/2016] [Indexed: 01/23/2023]
Abstract
Translocation of the dense nucleus along a gravity vector initiates mechanical remodeling of a cell, but the underlying mechanisms of cytoskeletal network and focal adhesion complex (FAC) reorganization in a mammalian cell remain unclear. We quantified the remodeling of an MC3T3-E1 cell placed in upward-, downward-, or edge-on-orientated substrate. Nucleus longitudinal translocation presents a high value in downward orientation at 24 h or in edge-on orientation at 72 h, which is consistent with orientation-dependent distribution of perinuclear actin stress fibers and vimentin cords. Redistribution of total FAC area and fractionized super mature adhesion number coordinates this dependence at short duration. This orientation-dependent remodeling is associated with nucleus flattering and lamin A/C phosphorylation. Actin depolymerization or Rho-associated protein kinase signaling inhibition abolishes the orientation dependence of nucleus translocation, whereas tubulin polymerization inhibition or vimentin disruption reserves the dependence. A biomechanical model is therefore proposed for integrating the mechanosensing of nucleus translocation with cytoskeletal remodeling and FAC reorganization induced by a gravity vector.-Zhang, C., Zhou, L., Zhang, F., Lü, D., Li, N., Zheng, L., Xu, Y., Li, Z., Sun, S., Long, M. Mechanical remodeling of normally sized mammalian cells under a gravity vector.
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Affiliation(s)
- Chen Zhang
- Center for Biomechanics and Bioengineering, Key Laboratory of Microgravity (National Microgravity Laboratory), and Beijing Key Laboratory of Engineered Construction and Mechanobiology, Institute of Mechanics, Chinese Academy of Sciences, Beijing, China
| | - Lüwen Zhou
- Center for Biomechanics and Bioengineering, Key Laboratory of Microgravity (National Microgravity Laboratory), and Beijing Key Laboratory of Engineered Construction and Mechanobiology, Institute of Mechanics, Chinese Academy of Sciences, Beijing, China
| | - Fan Zhang
- Center for Biomechanics and Bioengineering, Key Laboratory of Microgravity (National Microgravity Laboratory), and Beijing Key Laboratory of Engineered Construction and Mechanobiology, Institute of Mechanics, Chinese Academy of Sciences, Beijing, China
| | - Dongyuan Lü
- Center for Biomechanics and Bioengineering, Key Laboratory of Microgravity (National Microgravity Laboratory), and Beijing Key Laboratory of Engineered Construction and Mechanobiology, Institute of Mechanics, Chinese Academy of Sciences, Beijing, China
| | - Ning Li
- Center for Biomechanics and Bioengineering, Key Laboratory of Microgravity (National Microgravity Laboratory), and Beijing Key Laboratory of Engineered Construction and Mechanobiology, Institute of Mechanics, Chinese Academy of Sciences, Beijing, China
| | - Lu Zheng
- Center for Biomechanics and Bioengineering, Key Laboratory of Microgravity (National Microgravity Laboratory), and Beijing Key Laboratory of Engineered Construction and Mechanobiology, Institute of Mechanics, Chinese Academy of Sciences, Beijing, China
| | - Yanhong Xu
- Center for Biomechanics and Bioengineering, Key Laboratory of Microgravity (National Microgravity Laboratory), and Beijing Key Laboratory of Engineered Construction and Mechanobiology, Institute of Mechanics, Chinese Academy of Sciences, Beijing, China
| | - Zhan Li
- Center for Biomechanics and Bioengineering, Key Laboratory of Microgravity (National Microgravity Laboratory), and Beijing Key Laboratory of Engineered Construction and Mechanobiology, Institute of Mechanics, Chinese Academy of Sciences, Beijing, China
| | - Shujin Sun
- Center for Biomechanics and Bioengineering, Key Laboratory of Microgravity (National Microgravity Laboratory), and Beijing Key Laboratory of Engineered Construction and Mechanobiology, Institute of Mechanics, Chinese Academy of Sciences, Beijing, China
| | - Mian Long
- Center for Biomechanics and Bioengineering, Key Laboratory of Microgravity (National Microgravity Laboratory), and Beijing Key Laboratory of Engineered Construction and Mechanobiology, Institute of Mechanics, Chinese Academy of Sciences, Beijing, China
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Tavakolinejad A, Rabbani M, Janmaleki M. Effects of hypergravity on adipose-derived stem cell morphology, mechanical property and proliferation. Biochem Biophys Res Commun 2015; 464:473-9. [PMID: 26150354 DOI: 10.1016/j.bbrc.2015.06.160] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 06/24/2015] [Indexed: 01/28/2023]
Abstract
Alteration in specific inertial conditions can lead to changes in morphology, proliferation, mechanical properties and cytoskeleton of cells. In this report, the effects of hypergravity on morphology of Adipose-Derived Stem Cells (ADSCs) are indicated. ADSCs were repeatedly exposed to discontinuous hypergravity conditions of 10 g, 20 g, 40 g and 60 g by utilizing centrifuge (three times of 20 min exposure, with an interval of 40 min at 1 g). Cell morphology in terms of length, width and cell elongation index and cytoskeleton of actin filaments and microtubules were analyzed by image processing. Consistent changes observed in cell elongation index as morphological change. Moreover, cell proliferation was assessed and mechanical properties of cells in case of elastic modulus of cells were evaluated by Atomic Force Microscopy. Increase in proliferation and decrease in elastic modulus of cells are further results of this study. Staining ADSC was done to show changes in cytoskeleton of the cells associated to hypergravity condition specifically in microfilament and microtubule components. After exposing to hypergravity, significant changes were observed in microfilaments and microtubule density as components of cytoskeleton. It was concluded that there could be a relationship between changes in morphology and MFs as the main component of the cells.
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Affiliation(s)
- Alireza Tavakolinejad
- Medical Nanotechnology and Tissue Engineering Research Center, Taleghani Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohsen Rabbani
- Department of Biomedical Engineering, University of Isfahan, Isfahan, Iran.
| | - Mohsen Janmaleki
- Medical Nanotechnology and Tissue Engineering Research Center, Taleghani Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Rocca A, Marino A, Rocca V, Moscato S, de Vito G, Piazza V, Mazzolai B, Mattoli V, Ngo-Anh TJ, Ciofani G. Barium titanate nanoparticles and hypergravity stimulation improve differentiation of mesenchymal stem cells into osteoblasts. Int J Nanomedicine 2015; 10:433-45. [PMID: 25609955 PMCID: PMC4294648 DOI: 10.2147/ijn.s76329] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Background Enhancement of the osteogenic potential of mesenchymal stem cells (MSCs) is highly desirable in the field of bone regeneration. This paper proposes a new approach for the improvement of osteogenesis combining hypergravity with osteoinductive nanoparticles (NPs). Materials and methods In this study, we aimed to investigate the combined effects of hypergravity and barium titanate NPs (BTNPs) on the osteogenic differentiation of rat MSCs, and the hypergravity effects on NP internalization. To obtain the hypergravity condition, we used a large-diameter centrifuge in the presence of a BTNP-doped culture medium. We analyzed cell morphology and NP internalization with immunofluorescent staining and coherent anti-Stokes Raman scattering, respectively. Moreover, cell differentiation was evaluated both at the gene level with quantitative real-time reverse-transcription polymerase chain reaction and at the protein level with Western blotting. Results Following a 20 g treatment, we found alterations in cytoskeleton conformation, cellular shape and morphology, as well as a significant increment of expression of osteoblastic markers both at the gene and protein levels, jointly pointing to a substantial increment of NP uptake. Taken together, our findings suggest a synergistic effect of hypergravity and BTNPs in the enhancement of the osteogenic differentiation of MSCs. Conclusion The obtained results could become useful in the design of new approaches in bone-tissue engineering, as well as for in vitro drug-delivery strategies where an increment of nanocarrier internalization could result in a higher drug uptake by cell and/or tissue constructs.
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Affiliation(s)
- Antonella Rocca
- Istituto Italiano di Tecnologia, Center for Micro-BioRobotics @ SSSA, Pontedera, Italy ; Scuola Superiore Sant'Anna, The BioRobotics Institute, Pontedera, Italy
| | - Attilio Marino
- Istituto Italiano di Tecnologia, Center for Micro-BioRobotics @ SSSA, Pontedera, Italy ; Scuola Superiore Sant'Anna, The BioRobotics Institute, Pontedera, Italy
| | - Veronica Rocca
- Università di Pisa, Dipartimento di Ingegneria dell'Informazione, Pisa, Italy, Noordwijk, the Netherlands
| | - Stefania Moscato
- Università di Pisa, Dipartimento di Medicina Clinica e Sperimentale, Pisa, Italy
| | - Giuseppe de Vito
- Istituto Italiano di Tecnologia, Center for Nanotechnology Innovation @NEST, Pisa, Italy ; Scuola Normale Superiore, NEST, Pisa, Italy
| | - Vincenzo Piazza
- Istituto Italiano di Tecnologia, Center for Nanotechnology Innovation @NEST, Pisa, Italy
| | - Barbara Mazzolai
- Istituto Italiano di Tecnologia, Center for Micro-BioRobotics @ SSSA, Pontedera, Italy
| | - Virgilio Mattoli
- Istituto Italiano di Tecnologia, Center for Micro-BioRobotics @ SSSA, Pontedera, Italy
| | - Thu Jennifer Ngo-Anh
- Directorate of Human Spaceflight and Operations, European Space Agency, Noordwijk, the Netherlands
| | - Gianni Ciofani
- Istituto Italiano di Tecnologia, Center for Micro-BioRobotics @ SSSA, Pontedera, Italy
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Vorselen D, Roos WH, MacKintosh FC, Wuite GJL, van Loon JJWA. The role of the cytoskeleton in sensing changes in gravity by nonspecialized cells. FASEB J 2013; 28:536-47. [PMID: 24249634 DOI: 10.1096/fj.13-236356] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
A large body of evidence indicates that single cells in vitro respond to changes in gravity, and that this response might play an important role for physiological changes at the organism level during spaceflight. Gravity can lead to changes in cell proliferation, differentiation, signaling, and gene expression. At first glance, gravitational forces seem too small to affect bodies with the size of a cell. Thus, the initial response to gravity is both puzzling and important for understanding physiological changes in space. This also offers a unique environment to study the mechanical response of cells. In the past 2 decades, important steps have been made in the field of mechanobiology, and we use these advances to reevaluate the response of single cells to changes in gravity. Recent studies have focused on the cytoskeleton as initial gravity sensor. Thus, we review the observed changes in the cytoskeleton in a microgravity environment, both during spaceflight and in ground-based simulation techniques. We also evaluate to what degree the current experimental evidence supports the cytoskeleton as primary gravity sensor. Finally, we consider how the cytoskeleton itself could be affected by changed gravity. To make the next step toward understanding the response of cells to altered gravity, the challenge will be to track changes quantitatively and on short timescales.
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Affiliation(s)
- Daan Vorselen
- 1Department of Oral Cell Biology, Academic Centre for Dentistry Amsterdam (ACTA), Office 11N15, Gustav Mahler Laan 3004, 1081LA, Amsterdam, the Netherlands.
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Prodanov L, van Loon JJWA, te Riet J, Jansen JA, Walboomers XF. Substrate nanotexture and hypergravity through centrifugation enhance initial osteoblastogenesis. Tissue Eng Part A 2012; 19:114-24. [PMID: 22871341 DOI: 10.1089/ten.tea.2012.0267] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Mimicking the structural nanomolecular extracellular matrix with synthetically designed nanosized materials is a relatively new approach, which can be applied in the field of bone tissue engineering. Likewise, bone tissue-engineered constructs can be aided in their development by the use of several types of mechanical stimuli. In this study, we wanted to combine nanotextured biomaterials and centrifugation in one multifactorial system. Mesenchymal stem cells were isolated from rat bone marrow, and cultured on a nanogrooved polystyrene substrate (200-nm-wide pitch with a depth of 50 nm). Constant centrifugation of 10 g was applied to cells up to 7 days. Results showed that on a nanogrooved substrate osteoblast-like cells align parallel to the groove direction. Centrifugation of 10 g also affected cell morphology on a smooth surface. Moreover, cell alignment was significantly reduced for cells grown on nanogrooved substrates, which were subsequently subjected to centrifugation. Independently, both stimuli increased the number of cells after 7 days of culture. However, when both stimuli were combined, an additive effect on cell number was observed, followed by an enhanced effect on osteocalcin mRNA expression and matrix mineralization. In conclusion, biomaterial surface modification as well as centrifugation are effective means to enhance bone cell behavior, moreover, readily available to many tissue engineers.
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Affiliation(s)
- Ljupcho Prodanov
- Department of Biomaterials, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
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Prodanov L, te Riet J, Lamers E, Domanski M, Luttge R, van Loon JJWA, Jansen JA, Walboomers XF. The interaction between nanoscale surface features and mechanical loading and its effect on osteoblast-like cells behavior. Biomaterials 2011; 31:7758-65. [PMID: 20647152 DOI: 10.1016/j.biomaterials.2010.06.050] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2010] [Accepted: 06/28/2010] [Indexed: 11/18/2022]
Abstract
Osteoblasts respond to mechanical stimulation by changing morphology, gene expression and matrix mineralization. Introducing surface topography on biomaterials, independently of mechanical loading, has been reported to give similar effects. In the current study, using a nanotextured surface, and mechanical loading, we aimed to develop a multi-factorial model in which both parameters interact. Mechanical stimulation to osteoblast-like cells was applied by longitudinal stretch in parallel direction to the nanotexture (300 nm wide and 60 nm deep grooves), with frequency of 1 Hz and stretch magnitude varying from 1% to 8%. Scanning electron microscopy showed that osteoblast-like cells subjected to mechanical loading oriented perpendicularly to the stretch direction. When cultured on nanotextured surfaces, cells aligned parallel to the texture. However, the parallel cell direction to the nanotextured surface was lost and turned to perpendicular when parallel stretch to the nanotexture, greater than 3% was applied to the cells. This phenomenon could not be achieved when a texture with micro-sized dimensions was used. Moreover, a significant synergistic effect on upregulation of fibronectin and Cfba was observed when dual stimulation was used. These findings can lead to a development of new biomimetic materials that can guide morphogenesis in tissue repair and bone remodeling.
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Affiliation(s)
- Ljupcho Prodanov
- Radboud University Nijmegen Medical Centre, Department of Biomaterials, Nijmegen, The Netherlands
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Herranz R, Benguría A, Laván DA, López-Vidriero I, Gasset G, Javier Medina F, van Loon JJWA, Marco R. Spaceflight-related suboptimal conditions can accentuate the altered gravity response of Drosophila transcriptome. Mol Ecol 2010; 19:4255-64. [PMID: 20819157 DOI: 10.1111/j.1365-294x.2010.04795.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Genome-wide transcriptional profiling shows that reducing gravity levels during Drosophila metamorphosis in the International Space Station (ISS) causes important alterations in gene expression: a large set of differentially expressed genes (DEGs) are observed compared to 1g controls. However, the preparation procedures for spaceflight and the nonideal environmental conditions on board the ISS subject the organisms to additional environmental stresses that demonstrably affect gene expression. Simulated microgravity experiments performed on the ground, under ideal conditions for the flies, using the random position machine (RPM), show much more subtle effects on gene expression. However, when the ground experiments are repeated under conditions designed to reproduce the additional environmental stresses imposed by spaceflight procedures, 79% of the DEGs detected in the ISS are reproduced by the RPM experiment. Gene ontology analysis of them shows they are genes that affect respiratory activity, developmental processes and stress-related changes. Here, we analyse the effects of microgravity on gene expression in relation to the environmental stresses imposed by spaceflight. Analysis using 'gene expression dynamics inspector' (GEDI) self-organizing maps reveals a subtle response of the transcriptome to microgravity. Remarkably, hypergravity simulation induces similar response of the transcriptome, but in the opposite direction, i.e. the genes promoted under microgravity are usually suppressed under hypergravity. These results suggest that the transcriptome is finely tuned to normal gravity and that microgravity, together with environmental constraints associated with space experiments, can have profound effects on gene expression.
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Affiliation(s)
- Raul Herranz
- Departamento de Bioquímica & Instituto de Investigaciones Biomédicas 'Alberto Sols' (UAM-CSIC), C/Arzobispo Morcillo, 4 Madrid, 28029 SpainCentro de Investigaciones Biológicas (CSIC), Ramiro de Maeztu 9, E-28040, Madrid, SpainCentro Nacional de Biotecnología (UAM-CSIC), Madrid, SpainGenomics Unit. Centro Nacional de Investigaciones Cardiovasculares, C/Melchor Fernández Almagro, 3. Madrid, SpainGSBMS, Université Paul Sabatier, Toulouse, FranceDutch Experiment Support Center, DESC at OCB-ACTA, VU-University and Univ. of Amsterdam, Amsterdam, the Netherlands
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