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Schmitz J, Güntürkün O, Ocklenburg S. Building an Asymmetrical Brain: The Molecular Perspective. Front Psychol 2019; 10:982. [PMID: 31133928 PMCID: PMC6524718 DOI: 10.3389/fpsyg.2019.00982] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 04/15/2019] [Indexed: 12/17/2022] Open
Abstract
The brain is one of the most prominent examples for structural and functional differences between the left and right half of the body. For handedness and language lateralization, the most widely investigated behavioral phenotypes, only a small fraction of phenotypic variance has been explained by molecular genetic studies. Due to environmental factors presumably also playing a role in their ontogenesis and based on first molecular evidence, it has been suggested that functional hemispheric asymmetries are partly under epigenetic control. This review article aims to elucidate the molecular factors underlying hemispheric asymmetries and their association with inner organ asymmetries. While we previously suggested that epigenetic mechanisms might partly account for the missing heritability of handedness, this article extends this idea by suggesting possible alternatives for transgenerational transmission of epigenetic states that do not require germ line epigenetic transmission. This is in line with a multifactorial model of hemispheric asymmetries, integrating genetic, environmental, and epigenetic influencing factors in their ontogenesis.
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Affiliation(s)
- Judith Schmitz
- Biopsychology, Department of Psychology, Institute of Cognitive Neuroscience, Ruhr University Bochum, Bochum, Germany
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52
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Bérard A, Levin M, Sadler T, Healy D. Selective Serotonin Reuptake Inhibitor Use During Pregnancy and Major Malformations: The Importance of Serotonin for Embryonic Development and the Effect of Serotonin Inhibition on the Occurrence of Malformations. Bioelectricity 2019; 1:18-29. [PMID: 34471805 DOI: 10.1089/bioe.2018.0003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Bioelectric signaling is transduced by neurotransmitter pathways in many cell types. One of the key mediators of bioelectric control mechanisms is serotonin, and its transporter SERT, which is targeted by a broad class of blocker drugs (selective serotonin reuptake inhibitors [SSRIs]). Studies showing an increased risk of multiple malformations associated with gestational use of SSRI have been accumulating but debate remains on whether SSRI as a class has the potential to generate these malformations. This review highlights the importance of serotonin for embryonic development; the effect of serotonin inhibition during early pregnancy on the occurrence of multiple diverse malformations that have been shown to occur in human pregnancies; that the risks outweigh the benefits of SSRI use during gestation in populations of mild to moderately depressed pregnant women, which encompass the majority of pregnant depressed women; and that the malformations seen in human pregnancies constitute a pattern of malformations consistent with the known mechanisms of action of SSRIs. We present at least three mechanisms by which SSRI can affect development. These studies highlight the relevance of basic bioelectric and neurotransmitter mechanism for biomedicine.
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Affiliation(s)
- Anick Bérard
- Faculty of Pharmacy, University of Montreal; Research Center, CHU Sainte-Justine, Montreal, Quebec, Canada
| | - Michael Levin
- Allen Discovery Center at Tufts University, Department of Biology, Medford, Massachusetts
| | - Thomas Sadler
- Department of Pediatrics, School of Medicine, University of Utah, Salt Lake City, Utah
| | - David Healy
- Department of Psychiatry, Hergest Unit, Bangor, United Kingdom
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53
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Ishibashi T, Hatori R, Maeda R, Nakamura M, Taguchi T, Matsuyama Y, Matsuno K. E and ID proteins regulate cell chirality and left-right asymmetric development in Drosophila. Genes Cells 2019; 24:214-230. [PMID: 30624823 DOI: 10.1111/gtc.12669] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 12/13/2018] [Accepted: 12/28/2018] [Indexed: 02/07/2023]
Abstract
How left-right (LR) asymmetric forms in the animal body is a fundamental problem in Developmental Biology. Although the mechanisms for LR asymmetry are well studied in some species, they are still poorly understood in invertebrates. We previously showed that the intrinsic LR asymmetry of cells (designated as cell chirality) drives LR asymmetric development in the Drosophila embryonic hindgut, although the machinery of the cell chirality formation remains elusive. Here, we found that the Drosophila homologue of the Id gene, extra macrochaetae (emc), is required for the normal LR asymmetric morphogenesis of this organ. Id proteins, including Emc, are known to interact with and inhibit E-box-binding proteins (E proteins), such as Drosophila Daughterless (Da). We found that the suppression of da by wild-type emc was essential for cell chirality formation and for normal LR asymmetric development of the embryonic hindgut. Myosin ID (MyoID), which encodes the Drosophila Myosin ID protein, is known to regulate cell chirality. We further showed that Emc-Da regulates cell chirality formation, in which Emc functions upstream of or parallel to MyoID. Abnormal Id-E protein regulation is involved in various human diseases. Our results suggest that defects in cell shape may contribute to the pathogenesis of such diseases.
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Affiliation(s)
- Tomoki Ishibashi
- Department of Biological Sciences, Osaka University, Toyonaka, Osaka, Japan
| | - Ryo Hatori
- Department of Biological Sciences, Osaka University, Toyonaka, Osaka, Japan
| | - Reo Maeda
- Department of Biological Science and Technology, Tokyo University of Science, Noda, Chiba, Japan
| | | | - Tomohiro Taguchi
- Department of Biological Science and Technology, Tokyo University of Science, Noda, Chiba, Japan
| | - Yoko Matsuyama
- Department of Biological Sciences, Osaka University, Toyonaka, Osaka, Japan
| | - Kenji Matsuno
- Department of Biological Sciences, Osaka University, Toyonaka, Osaka, Japan
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54
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Chiral Neuronal Motility: The Missing Link between Molecular Chirality and Brain Asymmetry. Symmetry (Basel) 2019. [DOI: 10.3390/sym11010102] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Left–right brain asymmetry is a fundamental property observed across phyla from invertebrates to humans, but the mechanisms underlying its formation are still largely unknown. Rapid progress in our knowledge of the formation of body asymmetry suggests that brain asymmetry might be controlled by the same mechanisms. However, most of the functional brain laterality, including language processing and handedness, does not share common mechanisms with visceral asymmetry. Accumulating evidence indicates that asymmetry is manifested as chirality at the single cellular level. In neurons, the growth cone filopodia at the tips of neurites exhibit a myosin V-dependent, left-helical, and right-screw rotation, which drives the clockwise circular growth of neurites on adhesive substrates. Here, I propose an alternative model for the formation of brain asymmetry that is based on chiral neuronal motility. According to this chiral neuron model, the molecular chirality of actin filaments and myosin motors is converted into chiral neuronal motility, which is in turn transformed into the left–right asymmetry of neural circuits and lateralized brain functions. I also introduce automated, numerical, and quantitative methods to analyze the chirality and the left–right asymmetry that would enable the efficient testing of the model and to accelerate future investigations in this field.
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55
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Alexander-Bloch AF, Mathias SR, Fox PT, Olvera RL, Göring HHH, Duggirala R, Curran JE, Blangero J, Glahn DC. Human Cortical Thickness Organized into Genetically-determined Communities across Spatial Resolutions. Cereb Cortex 2019; 29:106-118. [PMID: 29190330 PMCID: PMC6676978 DOI: 10.1093/cercor/bhx309] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Revised: 10/19/2017] [Indexed: 12/13/2022] Open
Abstract
The cerebral cortex may be organized into anatomical genetic modules, communities of brain regions with shared genetic influences via pleiotropy. Such modules could represent novel phenotypes amenable to large-scale gene discovery. This modular structure was investigated with network analysis of in vivo MRI of extended pedigrees, revealing a "multiscale" structure where smaller and larger modules exist simultaneously and in partially overlapping fashion across spatial scales, in contrast to prior work suggesting a specific number of cortical thickness modules. Inter-regional genetic correlations, gene co-expression patterns and computational models indicate that two simple organizational principles account for a large proportion of the apparent complexity in the network of genetic correlations. First, regions are strongly genetically correlated with their homologs in the opposite cerebral hemisphere. Second, regions are strongly genetically correlated with nearby regions in the same hemisphere, with an initial steep decrease in genetic correlation with anatomical distance, followed by a more gradual decline. Understanding underlying organizational principles of genetic influence is a critical step towards a mechanistic model of how specific genes influence brain anatomy and mediate neuropsychiatric risk.
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Affiliation(s)
| | - Samuel R Mathias
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
- Olin Neuropsychiatry Research Center, Institute of Living, Hartford, CT, USA
| | - Peter T Fox
- South Texas Diabetes and Obesity Institute, University of Texas Health Science Center at San Antonio, TX, USA
- University of Texas of the Rio Grande Valley, Brownsville, TX, USA
| | - Rene L Olvera
- South Texas Diabetes and Obesity Institute, University of Texas Health Science Center at San Antonio, TX, USA
- University of Texas of the Rio Grande Valley, Brownsville, TX, USA
| | - Harold H H Göring
- South Texas Diabetes and Obesity Institute, University of Texas Health Science Center at San Antonio, TX, USA
- University of Texas of the Rio Grande Valley, Brownsville, TX, USA
| | - Ravi Duggirala
- South Texas Diabetes and Obesity Institute, University of Texas Health Science Center at San Antonio, TX, USA
- University of Texas of the Rio Grande Valley, Brownsville, TX, USA
| | - Joanne E Curran
- South Texas Diabetes and Obesity Institute, University of Texas Health Science Center at San Antonio, TX, USA
- University of Texas of the Rio Grande Valley, Brownsville, TX, USA
| | - John Blangero
- South Texas Diabetes and Obesity Institute, University of Texas Health Science Center at San Antonio, TX, USA
- University of Texas of the Rio Grande Valley, Brownsville, TX, USA
| | - David C Glahn
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
- Olin Neuropsychiatry Research Center, Institute of Living, Hartford, CT, USA
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56
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Ray P, Chin AS, Worley KE, Fan J, Kaur G, Wu M, Wan LQ. Intrinsic cellular chirality regulates left-right symmetry breaking during cardiac looping. Proc Natl Acad Sci U S A 2018; 115:E11568-E11577. [PMID: 30459275 PMCID: PMC6294912 DOI: 10.1073/pnas.1808052115] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The vertebrate body plan is overall symmetrical but left-right (LR) asymmetric in the shape and positioning of internal organs. Although several theories have been proposed, the biophysical mechanisms underlying LR asymmetry are still unclear, especially the role of cell chirality, the LR asymmetry at the cellular level, on organ asymmetry. Here with developing chicken embryos, we examine whether intrinsic cell chirality or handedness regulates cardiac C looping. Using a recently established biomaterial-based 3D culture platform, we demonstrate that chick cardiac cells before and during C looping are intrinsically chiral and exhibit dominant clockwise rotation in vitro. We further show that cells in the developing myocardium are chiral as evident by a rightward bias of cell alignment and a rightward polarization of the Golgi complex, correlating with the direction of cardiac tube rotation. In addition, there is an LR polarized distribution of N-cadherin and myosin II in the myocardium before the onset of cardiac looping. More interestingly, the reversal of cell chirality via activation of the protein kinase C signaling pathway reverses the directionality of cardiac looping, accompanied by a reversal in cellular biases on the cardiac tube. Our results suggest that myocardial cell chirality regulates cellular LR symmetry breaking in the heart tube and the resultant directionality of cardiac looping. Our study provides evidence of an intrinsic cellular chiral bias leading to LR symmetry breaking during directional tissue rotation in vertebrate development.
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Affiliation(s)
- Poulomi Ray
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180
- Center for Biotechnology & Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180
| | - Amanda S Chin
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180
- Center for Biotechnology & Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180
| | - Kathryn E Worley
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180
- Center for Biotechnology & Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180
| | - Jie Fan
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180
- Center for Biotechnology & Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180
| | - Gurleen Kaur
- Department of Biology, Rensselaer Polytechnic Institute, Troy, NY 12180
| | - Mingfu Wu
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, NY 12208
| | - Leo Q Wan
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180;
- Center for Biotechnology & Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180
- Department of Biology, Rensselaer Polytechnic Institute, Troy, NY 12180
- Center for Modeling, Simulation and Imaging in Medicine, Rensselaer Polytechnic Institute, Troy, NY 12180
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57
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Epithelial Cell Chirality Revealed by Three-Dimensional Spontaneous Rotation. Proc Natl Acad Sci U S A 2018; 115:12188-12193. [PMID: 30429314 DOI: 10.1073/pnas.1805932115] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Our understanding of the left-right (LR) asymmetry of embryonic development, in particular the contribution of intrinsic handedness of the cell or cell chirality, is limited due to the confounding systematic and environmental factors during morphogenesis and a ack of physiologically relevant in vitro 3D platforms. Here we report an efficient two-layered biomaterial platform for determining the chirality of individual cells, cell aggregates, and self-organized hollow epithelial spheroids. This bioengineered niche provides a uniform defined axis allowing for cells to rotate spontaneously with a directional bias toward either clockwise or counterclockwise directions. Mechanistic studies reveal an actin-dependent, cell-intrinsic property of 3D chirality that can be mediated by actin cross-linking via α-actinin-1. Our findings suggest that the gradient of extracellular matrix is an important biophysicochemical cue influencing cell polarity and chirality. Engineered biomaterial systems can serve as an effective platform for studying developmental asymmetry and screening for environmental factors causing birth defects.
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58
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Ferreira RR, Pakula G, Klaeyle L, Fukui H, Vilfan A, Supatto W, Vermot J. Chiral Cilia Orientation in the Left-Right Organizer. Cell Rep 2018; 25:2008-2016.e4. [DOI: 10.1016/j.celrep.2018.10.069] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 09/13/2018] [Accepted: 10/18/2018] [Indexed: 01/28/2023] Open
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59
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Byrnes KG, McDermott K, Coffey JC. Development of mesenteric tissues. Semin Cell Dev Biol 2018; 92:55-62. [PMID: 30347243 DOI: 10.1016/j.semcdb.2018.10.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 10/10/2018] [Indexed: 02/06/2023]
Abstract
Mesothelial, neurovascular, lymphatic, adipose and mesenchymal tissues make up the mesentery. These tissues are pathobiologically important for numerous reasons. Collectively, they form a continuous, discrete and substantive organ. Additionally, they maintain abdominal digestive organs in position and in continuity with other systems. Furthermore, as they occupy a central position, they mediate transmission of signals between the abdominal digestive system and the remainder of the body. Despite this physiologic centrality, mesenteric tissue development has received little investigatory focus. However, recent advances in our understanding of anatomy demonstrate continuity between all mesenteric tissues, thereby linking previously unrelated studies. In this review, we examine the development of mesenteric tissue in normality and in the setting of congenital abnormalities.
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Affiliation(s)
- Kevin Gerard Byrnes
- Department of Surgery, University Hospital Limerick, Limerick, Ireland; Graduate Entry Medical School, University of Limerick, Limerick, Ireland
| | - Kieran McDermott
- Graduate Entry Medical School, University of Limerick, Limerick, Ireland
| | - John Calvin Coffey
- Department of Surgery, University Hospital Limerick, Limerick, Ireland; Graduate Entry Medical School, University of Limerick, Limerick, Ireland; Centre for Interventions in Infection, Inflammation and Immunity (4i), University of Limerick, Limerick, Ireland.
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60
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Bioelectrical coupling in multicellular domains regulated by gap junctions: A conceptual approach. Bioelectrochemistry 2018; 123:45-61. [DOI: 10.1016/j.bioelechem.2018.04.013] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 04/13/2018] [Accepted: 04/17/2018] [Indexed: 12/16/2022]
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61
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Warga RM, Kane DA. Wilson cell origin for kupffer's vesicle in the zebrafish. Dev Dyn 2018; 247:1057-1069. [DOI: 10.1002/dvdy.24657] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 06/19/2018] [Accepted: 07/03/2018] [Indexed: 11/06/2022] Open
Affiliation(s)
- Rachel M. Warga
- Department of Biological Sciences; Western Michigan University; Kalamazoo Michigan
| | - Donald A. Kane
- Department of Biological Sciences; Western Michigan University; Kalamazoo Michigan
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62
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Sivakumar A, Mahadevan A, Lauer ME, Narvaez RJ, Ramesh S, Demler CM, Souchet NR, Hascall VC, Midura RJ, Garantziotis S, Frank DB, Kimata K, Kurpios NA. Midgut Laterality Is Driven by Hyaluronan on the Right. Dev Cell 2018; 46:533-551.e5. [PMID: 30174180 PMCID: PMC6207194 DOI: 10.1016/j.devcel.2018.08.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 06/01/2018] [Accepted: 08/01/2018] [Indexed: 11/24/2022]
Abstract
For many years, biologists have focused on the role of Pitx2, expressed on the left side of developing embryos, in governing organ laterality. Here, we identify a different pathway during left-right asymmetry initiated by the right side of the embryo. Surprisingly, this conserved mechanism is orchestrated by the extracellular glycosaminoglycan, hyaluronan (HA) and is independent of Pitx2 on the left. Whereas HA is normally synthesized bilaterally as a simple polysaccharide, we show that covalent modification of HA by the enzyme Tsg6 on the right triggers distinct cell behavior necessary to drive the conserved midgut rotation and to pattern gut vasculature. HA disruption in chicken and Tsg6-/- mice results in failure to initiate midgut rotation and perturbs vascular development predisposing to midgut volvulus. Our study leads us to revise the current symmetry-breaking paradigm in vertebrates and demonstrates how enzymatic modification of HA matrices can execute the blueprint of organ laterality.
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Affiliation(s)
- Aravind Sivakumar
- Department of Molecular Medicine, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
| | - Aparna Mahadevan
- Department of Molecular Medicine, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
| | - Mark E Lauer
- Department of Biomedical Engineering, Cleveland Clinic Lerner Research Institute, Cleveland, OH 44195, USA
| | - Ricky J Narvaez
- Department of Molecular Medicine, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
| | - Siddesh Ramesh
- Department of Molecular Medicine, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
| | - Cora M Demler
- Department of Molecular Medicine, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
| | - Nathan R Souchet
- Department of Molecular Medicine, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
| | - Vincent C Hascall
- Department of Biomedical Engineering, Cleveland Clinic Lerner Research Institute, Cleveland, OH 44195, USA
| | - Ron J Midura
- Department of Biomedical Engineering, Cleveland Clinic Lerner Research Institute, Cleveland, OH 44195, USA
| | - Stavros Garantziotis
- Division of Intramural Research, National Institute of Environmental Health Sciences, Research Triangle Park, Durham, NC, USA
| | - David B Frank
- Division of Pediatric Cardiology, Department of Pediatrics, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Koji Kimata
- Institute of Molecular Medical Sciences, Aichi Medical University, Nagakute, Aichi, Japan
| | - Natasza A Kurpios
- Department of Molecular Medicine, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA.
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63
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de Kovel CGF, Lisgo SN, Fisher SE, Francks C. Subtle left-right asymmetry of gene expression profiles in embryonic and foetal human brains. Sci Rep 2018; 8:12606. [PMID: 30181561 PMCID: PMC6123426 DOI: 10.1038/s41598-018-29496-2] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 07/10/2018] [Indexed: 12/11/2022] Open
Abstract
Left-right laterality is an important aspect of human -and in fact all vertebrate- brain organization for which the genetic basis is poorly understood. Using RNA sequencing data we contrasted gene expression in left- and right-sided samples from several structures of the anterior central nervous systems of post mortem human embryos and foetuses. While few individual genes stood out as significantly lateralized, most structures showed evidence of laterality of their overall transcriptomic profiles. These left-right differences showed overlap with age-dependent changes in expression, indicating lateralized maturation rates, but not consistently in left-right orientation over all structures. Brain asymmetry may therefore originate in multiple locations, or if there is a single origin, it is earlier than 5 weeks post conception, with structure-specific lateralized processes already underway by this age. This pattern is broadly consistent with the weak correlations reported between various aspects of adult brain laterality, such as language dominance and handedness.
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Affiliation(s)
- Carolien G F de Kovel
- Language and Genetics Department, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands
| | - Steven N Lisgo
- Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Simon E Fisher
- Language and Genetics Department, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands
| | - Clyde Francks
- Language and Genetics Department, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands.
- Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands.
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64
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Takahashi M, Hosomichi K, Yamaguchi T, Nagahama R, Yoshida H, Marazita ML, Weinberg SM, Maki K, Tajima A. Exploration of genetic factors determining cleft side in a pair of monozygotic twins with mirror-image cleft lip and palate using whole-genome sequencing and comparison of craniofacial morphology. Arch Oral Biol 2018; 96:33-38. [PMID: 30172943 DOI: 10.1016/j.archoralbio.2018.08.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2018] [Revised: 08/15/2018] [Accepted: 08/17/2018] [Indexed: 12/15/2022]
Abstract
OBJECTIVE The aim of the present study is to explore genetic factors determining difference of cleft side using whole-genome sequencing and evaluation of craniofacial morphology using cephalometric analysis between Japanese monozygotic (MZ) twins with mirror-image cleft lip and palate (CLP). DESIGN We selected a Japanese MZ twin pair (MZ-A and MZ-B) affected with unilateral CLP who are discordant for cleft side (left/right) and conducted whole-genome sequencing to identify genetic factors determining cleft side. Moreover, we compared their craniofacial morphologies using cephalograms. RESULTS Whole-genome sequencing results suggested that no discordant DNA variants were found between MZ-A and MZ-B. The comparison of craniofacial morphology between the MZ twins revealed that MZ-B had maxillary deficiency and slightly more mandibular protrusion than MZ-A. CONCLUSIONS It is indicated that environmental factors might be a critical factor that influences the determination of difference of cleft side in orofacial clefts. In addition, we found some differences in craniofacial morphology between MZ-A and MZ-B. Our findings suggest that various environmental factors, such as epigenetics, might be a critical factor that influences the determination of difference of cleft side in CLP rather than inherited genetic factors.
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Affiliation(s)
- Masahiro Takahashi
- Department of Orthodontics, School of Dentistry, Showa University, Tokyo, Japan.
| | - Kazuyoshi Hosomichi
- Department of Bioinformatics and Genomics, Graduate School of Advanced Preventive Medical Sciences, Kanazawa University, Ishikawa, Japan
| | - Tetsutaro Yamaguchi
- Department of Orthodontics, School of Dentistry, Showa University, Tokyo, Japan; Center for Craniofacial and Dental Genetics, Department of Oral Biology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Ryo Nagahama
- Department of Orthodontics, School of Dentistry, Showa University, Tokyo, Japan
| | - Hiroshi Yoshida
- Department of Orthodontics, School of Dentistry, Showa University, Tokyo, Japan
| | - Mary L Marazita
- Center for Craniofacial and Dental Genetics, Department of Oral Biology, University of Pittsburgh, Pittsburgh, PA, USA; Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA; Clinical and Translational Science Institute, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA; Department of Psychiatry, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Seth M Weinberg
- Center for Craniofacial and Dental Genetics, Department of Oral Biology, University of Pittsburgh, Pittsburgh, PA, USA; Department of Anthropology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Koutaro Maki
- Department of Orthodontics, School of Dentistry, Showa University, Tokyo, Japan
| | - Atsushi Tajima
- Department of Bioinformatics and Genomics, Graduate School of Advanced Preventive Medical Sciences, Kanazawa University, Ishikawa, Japan
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65
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Kempeneers C, Chilvers MA. To beat, or not to beat, that is question! The spectrum of ciliopathies. Pediatr Pulmonol 2018; 53:1122-1129. [PMID: 29938933 DOI: 10.1002/ppul.24078] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2018] [Accepted: 05/19/2018] [Indexed: 12/14/2022]
Abstract
Cilia are widely distributed throughout the human body, and have numerous roles in physiology, development, and disease. Ciliary ultrastructure is complex, consisting of nine parallel microtubules doublets, with or without motor dynein arms and a central pair of microtubules. Classification of cilia has evolved over time, and currently, four main classes are described: motile and non-motile cilia with a "9 + 2" structure, and motile and non-motile cilia with a "9 + 0" structure, which depend on the presence or absence of dynein arms and a central pair. Ciliopathies are inherited multisystem disorders of cilia, and may present with a varied spectrum of genotypes and phenotypes. Motor and sensory ciliopathies were historically considered as distinct dysfunctions of motile and non-motile cilia, but recent data indicate that the classical features of motor and sensory cilia may overlap.
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Affiliation(s)
- Céline Kempeneers
- Pediatric Respirology, Department of Pediatrics, University Hospital Liège, Liège, Belgium
| | - Mark A Chilvers
- Division of Respirology, Department of Pediatrics, University of British Columbia and British Columbia Children's Hospital, Vancouver, BC, Canada
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66
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Wei L, Xu F, Wang Y, Cai Z, Yu W, He C, Jiang Q, Xu X, Guo W, Wang X. The Molecular Differentiation of Anatomically Paired Left and Right Mantles of the Pacific Oyster Crassostrea gigas. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2018; 20:425-435. [PMID: 29594756 DOI: 10.1007/s10126-018-9806-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 03/05/2018] [Indexed: 06/08/2023]
Abstract
Left-right (L-R) asymmetry is controlled by gene regulation pathways for the L-R axis, and in vertebrates, the gene Pitx2 in TGF-β signaling pathway plays important roles in the asymmetrical formation of organs. However, less is known about the asymmetries of anatomically identical paired organs, as well as the transcriptional regulation mechanism of the gene Pitx in invertebrates. Here, we report the molecular biological differences between the left and right mantles of an invertebrate, the Pacific oyster Crassostrea gigas, and propose one possible mechanism underlying those differences. RNA sequencing (RNA-seq) analysis indicated that the paired organs showed different gene expression patterns, suggesting possible functional differences in shell formation, pheromone signaling, nerve conduction, the stress response, and other physiological processes. RNA-seq and real-time qPCR analysis indicated high right-side expression of the Pitx homolog (cgPitx) in oyster mantle, supporting a conserved role for Pitx in controlling asymmetry. Methylation-dependent restriction-site associated DNA sequencing (MethylRAD) identified a methylation site in the promoter region of cgPitx and showed significantly different methylation levels between the left and right mantles. This is the first report, to our knowledge, of such a difference in methylation in spiralians, and it was further confirmed in 18 other individuals by using a pyrosequencing assay. The miRNome analysis and the TGF-β receptor/Smad inhibition experiment further supported that several genes in TGF-β signaling pathway may be related with the L/R asymmetry of oyster mantles. These results suggested that the molecular differentiation of the oyster's paired left and right mantles is significant, TGF-β signaling pathway could be involved in establishing or maintaining the asymmetry, and the cgPitx gene as one of genes in this pathway; the different methylation levels in its promoter regions between L/R mantles was the one of possible mechanisms regulating the left-right functional differentiation.
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Affiliation(s)
- Lei Wei
- School of Agriculture, Ludong University, Yantai, 264025, China
| | - Fei Xu
- Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China
| | - Yuzhi Wang
- School of Life Sciences, Shandong University, Jinan, 250100, China
| | - Zhongqiang Cai
- Changdao Enhancement and Experiment Station, Chinese Academy of Fishery Sciences, Changdao, 265800, China
| | - Wenchao Yu
- School of Agriculture, Ludong University, Yantai, 264025, China
| | - Cheng He
- School of Agriculture, Ludong University, Yantai, 264025, China
| | - Qiuyun Jiang
- School of Agriculture, Ludong University, Yantai, 264025, China
| | - Xiqiang Xu
- Qingdao OE Biotechnology Company Limited, Qingdao, 266101, China
| | - Wen Guo
- Marine Biology Institute of Shandong Province, Qingdao, 266104, China
| | - Xiaotong Wang
- School of Agriculture, Ludong University, Yantai, 264025, China.
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Reprogramming the Stem Cell Behavior by Shear Stress and Electric Field Stimulation: Lab-on-a-Chip Based Biomicrofluidics in Regenerative Medicine. REGENERATIVE ENGINEERING AND TRANSLATIONAL MEDICINE 2018. [DOI: 10.1007/s40883-018-0071-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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68
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Inaki M, Hatori R, Nakazawa N, Okumura T, Ishibashi T, Kikuta J, Ishii M, Matsuno K, Honda H. Chiral cell sliding drives left-right asymmetric organ twisting. eLife 2018; 7:32506. [PMID: 29891026 PMCID: PMC5997448 DOI: 10.7554/elife.32506] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 05/06/2018] [Indexed: 11/23/2022] Open
Abstract
Polarized epithelial morphogenesis is an essential process in animal development. While this process is mostly attributed to directional cell intercalation, it can also be induced by other mechanisms. Using live-imaging analysis and a three-dimensional vertex model, we identified ‘cell sliding,’ a novel mechanism driving epithelial morphogenesis, in which cells directionally change their position relative to their subjacent (posterior) neighbors by sliding in one direction. In Drosophila embryonic hindgut, an initial left-right (LR) asymmetry of the cell shape (cell chirality in three dimensions), which occurs intrinsically before tissue deformation, is converted through LR asymmetric cell sliding into a directional axial twisting of the epithelial tube. In a Drosophila inversion mutant showing inverted cell chirality and hindgut rotation, cell sliding occurs in the opposite direction to that in wild-type. Unlike directional cell intercalation, cell sliding does not require junctional remodeling. Cell sliding may also be involved in other cases of LR-polarized epithelial morphogenesis. Many organs arise from simple sheets and tubes of cells. During development these sheets bend and deform into the more complex shape of the final organ. This can be seen, for example, in the hindgut of fruit flies, which is an organ that is equivalent to our intestines. Initially, the hindgut is a simple tube of cells. Later the hindgut develops a twist to the left that renders its right and left sides non-symmetrical. During twisting, the cells in the hindgut also change shape. It was not known how this shape change and other behaviors of the cells cause the hindgut to twist. Inaki et al. have now filmed how the hindgut develops in live fruit flies and produced computer simulations of the development process. The results suggest that a previously unidentified type of cell behavior called ‘cell sliding’ is responsible for twisting the hindgut. During sliding, the cells stay in contact with their neighbors as they move in a single direction. Sliding is triggered by the cells in the hindgut taking on a more symmetrical shape. Cell sliding may prove to be a common way to shape organs, many of which feature non-symmetrical twisted tubes of cells. In the future, learning how to control cell sliding could help researchers to create organs and biological structures in the laboratory that could be used in organ transplants and regenerative medicine.
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Affiliation(s)
- Mikiko Inaki
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka, Japan
| | - Ryo Hatori
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka, Japan
| | - Naotaka Nakazawa
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka, Japan
| | - Takashi Okumura
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka, Japan
| | - Tomoki Ishibashi
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka, Japan
| | - Junichi Kikuta
- Department of Immunology and Cell Biology, Graduate School of Medicine, Osaka University, Suita, Japan
| | - Masaru Ishii
- Department of Immunology and Cell Biology, Graduate School of Medicine, Osaka University, Suita, Japan
| | - Kenji Matsuno
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka, Japan
| | - Hisao Honda
- Department of Physiology and Cell Biology, Graduate School of Medicine, Kobe University, Kobe, Japan
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69
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Gourinchas G, Heintz U, Winkler A. Asymmetric activation mechanism of a homodimeric red light-regulated photoreceptor. eLife 2018; 7:e34815. [PMID: 29869984 PMCID: PMC6005682 DOI: 10.7554/elife.34815] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 06/03/2018] [Indexed: 12/18/2022] Open
Abstract
Organisms adapt to environmental cues using diverse signaling networks. In order to sense and integrate light for regulating various biological functions, photoreceptor proteins have evolved in a modular way. This modularity is targeted in the development of optogenetic tools enabling the control of cellular events with high spatiotemporal precision. However, the limited understanding of signaling mechanisms impedes the rational design of innovative photoreceptor-effector couples. Here, we reveal molecular details of signal transduction in phytochrome-regulated diguanylyl cyclases. Asymmetric structural changes of the full-length homodimer result in a functional heterodimer featuring two different photoactivation states. Structural changes around the cofactors result in a quasi-translational rearrangement of the distant coiled-coil sensor-effector linker. Eventually, this regulates enzymatic activity by modulating the dimer interface of the output domains. Considering the importance of phytochrome heterodimerization in plant signaling, our mechanistic details of asymmetric photoactivation in a bacterial system reveal novel aspects of the evolutionary adaptation of phytochromes.
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Affiliation(s)
| | - Udo Heintz
- Max Planck Institute for Medical ResearchHeidelbergGermany
| | - Andreas Winkler
- Institute of Biochemistry, Graz University of TechnologyGrazAustria
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70
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Neurocristopathies: New insights 150 years after the neural crest discovery. Dev Biol 2018; 444 Suppl 1:S110-S143. [PMID: 29802835 DOI: 10.1016/j.ydbio.2018.05.013] [Citation(s) in RCA: 104] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 05/16/2018] [Accepted: 05/17/2018] [Indexed: 12/12/2022]
Abstract
The neural crest (NC) is a transient, multipotent and migratory cell population that generates an astonishingly diverse array of cell types during vertebrate development. These cells, which originate from the ectoderm in a region lateral to the neural plate in the neural fold, give rise to neurons, glia, melanocytes, chondrocytes, smooth muscle cells, odontoblasts and neuroendocrine cells, among others. Neurocristopathies (NCP) are a class of pathologies occurring in vertebrates, especially in humans that result from the abnormal specification, migration, differentiation or death of neural crest cells during embryonic development. Various pigment, skin, thyroid and hearing disorders, craniofacial and heart abnormalities, malfunctions of the digestive tract and tumors can also be considered as neurocristopathies. In this review we revisit the current classification and propose a new way to classify NCP based on the embryonic origin of the affected tissues, on recent findings regarding the molecular mechanisms that drive NC formation, and on the increased complexity of current molecular embryology techniques.
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71
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Mapping cortical brain asymmetry in 17,141 healthy individuals worldwide via the ENIGMA Consortium. Proc Natl Acad Sci U S A 2018; 115:E5154-E5163. [PMID: 29764998 DOI: 10.1073/pnas.1718418115] [Citation(s) in RCA: 231] [Impact Index Per Article: 38.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Hemispheric asymmetry is a cardinal feature of human brain organization. Altered brain asymmetry has also been linked to some cognitive and neuropsychiatric disorders. Here, the ENIGMA (Enhancing NeuroImaging Genetics through Meta-Analysis) Consortium presents the largest-ever analysis of cerebral cortical asymmetry and its variability across individuals. Cortical thickness and surface area were assessed in MRI scans of 17,141 healthy individuals from 99 datasets worldwide. Results revealed widespread asymmetries at both hemispheric and regional levels, with a generally thicker cortex but smaller surface area in the left hemisphere relative to the right. Regionally, asymmetries of cortical thickness and/or surface area were found in the inferior frontal gyrus, transverse temporal gyrus, parahippocampal gyrus, and entorhinal cortex. These regions are involved in lateralized functions, including language and visuospatial processing. In addition to population-level asymmetries, variability in brain asymmetry was related to sex, age, and intracranial volume. Interestingly, we did not find significant associations between asymmetries and handedness. Finally, with two independent pedigree datasets (n = 1,443 and 1,113, respectively), we found several asymmetries showing significant, replicable heritability. The structural asymmetries identified and their variabilities and heritability provide a reference resource for future studies on the genetic basis of brain asymmetry and altered laterality in cognitive, neurological, and psychiatric disorders.
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72
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Cortés-Gómez AA, Romero D, Girondot M. Carapace asymmetry: A possible biomarker for metal accumulation in adult olive Ridleys marine turtles? MARINE POLLUTION BULLETIN 2018; 129:92-101. [PMID: 29680573 DOI: 10.1016/j.marpolbul.2018.02.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 02/06/2018] [Accepted: 02/08/2018] [Indexed: 06/08/2023]
Abstract
The Olive Ridley marine turtle (Lepidochelys olivacea) is characterized by individual morphological variability in the number and shape of scutes. The influence of pollutants on developmental instability and one of its consequences, the asymmetry of individuals, has been demonstrated in several species, especially invertebrates and some birds. However, the use of this asymmetry as a biomarker of contamination in adult individuals has never been explored. We developed an index to quantify developmental instability (DIx) based on the number and relative size of costal carapace scutes. The link between DIx and inorganic elements concentrations was explored in various tissues of stranded turtles from the Southern Mexican Pacific. The relationships between adult contamination and DIx could directly or indirectly reflect (i) the disruption of metal elimination in the adult stage dependent on embryonic perturbation and thus determining DIx, (ii) the difference in metal absorption dependent on DIx status, or (iii) DIx linked to other unknown factors.
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Affiliation(s)
- Adriana A Cortés-Gómez
- Laboratoire Écologie, Systématique et Évolution, Université Paris-Sud, AgroParisTech, CNRS, Université Paris Saclay, 91405 Orsay, France; Área de toxicología, Universidad de Murcia, 30100 Murcia, Spain.
| | - Diego Romero
- Área de toxicología, Universidad de Murcia, 30100 Murcia, Spain.
| | - Marc Girondot
- Laboratoire Écologie, Systématique et Évolution, Université Paris-Sud, AgroParisTech, CNRS, Université Paris Saclay, 91405 Orsay, France.
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73
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Silver BB, Nelson CM. The Bioelectric Code: Reprogramming Cancer and Aging From the Interface of Mechanical and Chemical Microenvironments. Front Cell Dev Biol 2018; 6:21. [PMID: 29560350 PMCID: PMC5845671 DOI: 10.3389/fcell.2018.00021] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Accepted: 02/15/2018] [Indexed: 12/12/2022] Open
Abstract
Cancer is a complex, heterogeneous group of diseases that can develop through many routes. Broad treatments such as chemotherapy destroy healthy cells in addition to cancerous ones, but more refined strategies that target specific pathways are usually only effective for a limited number of cancer types. This is largely due to the multitude of physiological variables that differ between cells and their surroundings. It is therefore important to understand how nature coordinates these variables into concerted regulation of growth at the tissue scale. The cellular microenvironment might then be manipulated to drive cells toward a desired outcome at the tissue level. One unexpected parameter, cellular membrane voltage (Vm), has been documented to exert control over cellular behavior both in culture and in vivo. Manipulating this fundamental cellular property influences a remarkable array of organism-wide patterning events, producing striking outcomes in both tumorigenesis as well as regeneration. These studies suggest that Vm is not only a key intrinsic cellular property, but also an integral part of the microenvironment that acts in both space and time to guide cellular behavior. As a result, there is considerable interest in manipulating Vm both to treat cancer as well as to regenerate organs damaged or deteriorated during aging. However, such manipulations have produced conflicting outcomes experimentally, which poses a substantial barrier to understanding the fundamentals of bioelectrical reprogramming. Here, we summarize these inconsistencies and discuss how the mechanical microenvironment may impact bioelectric regulation.
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Affiliation(s)
- Brian B. Silver
- Department of Molecular Biology, Princeton University, Princeton, NJ, United States
| | - Celeste M. Nelson
- Department of Molecular Biology, Princeton University, Princeton, NJ, United States
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ, United States
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74
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Absmaier M, Napieralski R, Schuster T, Aubele M, Walch A, Magdolen V, Dorn J, Gross E, Harbeck N, Noske A, Kiechle M, Schmitt M. PITX2 DNA-methylation predicts response to anthracycline-based adjuvant chemotherapy in triple-negative breast cancer patients. Int J Oncol 2018; 52:755-767. [PMID: 29328369 PMCID: PMC5807037 DOI: 10.3892/ijo.2018.4241] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Accepted: 10/19/2017] [Indexed: 12/11/2022] Open
Abstract
Triple-negative breast cancer (TNBC) constitutes a heterogeneous breast cancer subgroup with poor prognosis; survival rates are likely to be lower with TNBC compared to other breast cancer subgroups. For this disease, systemic adjuvant chemotherapy regimens often yield suboptimal clinical results. To improve treatment regimens in TNBC, identification of molecular biomarkers may help to select patients for individualized adjuvant therapy. Evidence has accumulated that determination of the methylation status of the PITX2 gene provides a predictive value in various breast cancer subgroups, either treated with endocrine-based therapy or anthracycline-containing chemotherapy. To further explore the validity of this novel predictive candidate biomarker, in the present exploratory retrospective study, determination of the PITX2 DNA-methylation status was assessed for non-metastatic TNBC patients treated with adjuvant anthracycline-based chemotherapy by molecular analysis of breast cancer tissues. The PITX2 DNA-methylation status was determined in fresh-frozen tumor tissue specimens (n=56) by methylation-specific qRT-PCR (qMSP) and the data related to disease-free and overall survival, applying an optimized DNA-methylation score of 6.35%. For non-metastatic TNBC patients treated with adjuvant systemic anthracycline-based chemotherapy, a low PITX2 DNA-methylation status (<6.35) defines TNBC patients with poor disease-free and overall survival. Univariate and multivariate analyses demonstrate the statistically independent predictive value of PITX2 DNA-methylation. For non-metastatic TNBC patients, selective determination of the PITX2 DNA-methylation status may serve as a cancer biomarker for predicting response to anthracycline-based adjuvant chemotherapy. The assay based on methylation of the PIXT2 gene can be applied to frozen and routinely available formalin-fixed, paraffin-embedded (FFPE) breast cancer tumor tissues that will not only define those TNBC patients who may benefit from anthracycline-based chemotherapy but also those who should be spared the necessity of such potentially toxic treatment. Such patients should be allocated to alternative treatment options.
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Affiliation(s)
- Magdalena Absmaier
- Department of Obstetrics and Gynecology, Technische Universität München, Munich, Germany
| | - Rudolf Napieralski
- Department of Obstetrics and Gynecology, Technische Universität München, Munich, Germany
| | - Tibor Schuster
- Institute of Medical Statistics and Epidemiology, Technische Universität München, Munich, Germany
| | - Michaela Aubele
- Institute of Pathology, Helmholtz Zentrum Muenchen, Neuherberg, Germany
| | - Axel Walch
- Institute of Pathology, Helmholtz Zentrum Muenchen, Neuherberg, Germany
| | - Viktor Magdolen
- Department of Obstetrics and Gynecology, Technische Universität München, Munich, Germany
| | - Julia Dorn
- Department of Obstetrics and Gynecology, Technische Universität München, Munich, Germany
| | - Eva Gross
- Department of Obstetrics and Gynecology, Technische Universität München, Munich, Germany
| | - Nadia Harbeck
- Breast Center, Klinikum der Ludwig Maximilians Universität München, Munich, Germany
| | - Aurelia Noske
- Department of Pathology and Pathological Anatomy, Technische Universität München, Munich, Germany
| | - Marion Kiechle
- Department of Obstetrics and Gynecology, Technische Universität München, Munich, Germany
| | - Manfred Schmitt
- Department of Obstetrics and Gynecology, Technische Universität München, Munich, Germany
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75
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McLaughlin KA, Levin M. Bioelectric signaling in regeneration: Mechanisms of ionic controls of growth and form. Dev Biol 2018; 433:177-189. [PMID: 29291972 PMCID: PMC5753428 DOI: 10.1016/j.ydbio.2017.08.032] [Citation(s) in RCA: 132] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 08/23/2017] [Accepted: 08/28/2017] [Indexed: 12/11/2022]
Abstract
The ability to control pattern formation is critical for the both the embryonic development of complex structures as well as for the regeneration/repair of damaged or missing tissues and organs. In addition to chemical gradients and gene regulatory networks, endogenous ion flows are key regulators of cell behavior. Not only do bioelectric cues provide information needed for the initial development of structures, they also enable the robust restoration of normal pattern after injury. In order to expand our basic understanding of morphogenetic processes responsible for the repair of complex anatomy, we need to identify the roles of endogenous voltage gradients, ion flows, and electric fields. In complement to the current focus on molecular genetics, decoding the information transduced by bioelectric cues enhances our knowledge of the dynamic control of growth and pattern formation. Recent advances in science and technology place us in an exciting time to elucidate the interplay between molecular-genetic inputs and important biophysical cues that direct the creation of tissues and organs. Moving forward, these new insights enable additional approaches to direct cell behavior and may result in profound advances in augmentation of regenerative capacity.
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Affiliation(s)
- Kelly A McLaughlin
- Allen Discovery Center, Department of Biology, Tufts University, 200 Boston Ave., Suite 4700, Medford, MA 02155, United States.
| | - Michael Levin
- Allen Discovery Center, Department of Biology, Tufts University, 200 Boston Ave., Suite 4700, Medford, MA 02155, United States
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76
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Niven JE, Frasnelli E. Insights into the evolution of lateralization from the insects. PROGRESS IN BRAIN RESEARCH 2018; 238:3-31. [DOI: 10.1016/bs.pbr.2018.06.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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77
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The Role of Cerl2 in the Establishment of Left-Right Asymmetries during Axis Formation and Heart Development. J Cardiovasc Dev Dis 2017; 4:jcdd4040023. [PMID: 29367552 PMCID: PMC5753124 DOI: 10.3390/jcdd4040023] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 12/06/2017] [Accepted: 12/07/2017] [Indexed: 12/13/2022] Open
Abstract
The formation of the asymmetric left-right (LR) body axis is one of the fundamental aspects of vertebrate embryonic development, and one still raising passionate discussions among scientists. Although the conserved role of nodal is unquestionable in this process, several of the details around this signaling cascade are still unanswered. To further understand this mechanism, we have been studying Cerberus-like 2 (Cerl2), an inhibitor of Nodal, and its role in the generation of asymmetries in the early vertebrate embryo. The absence of Cerl2 results in a wide spectrum of malformations commonly known as heterotaxia, which comprises defects in either global organ position (e.g., situs inversus totalis), reversed orientation of at least one organ (e.g., situs ambiguus), and mirror images of usually asymmetric paired organs (e.g., left or right isomerisms of the lungs). Moreover, these laterality defects are frequently associated with congenital heart diseases (e.g., transposition of the great arteries, or atrioventricular septal defects). Here, reviewing the knowledge on the establishment of LR asymmetry in mouse embryos, the emerging conclusion is that as necessary as is the activation of the Nodal signaling cascade, the tight control that Cerl2-mediates on Nodal signaling is equally important, and that generates a further regionalized LR genetic program in the proper time and space.
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78
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Burdine RD, Grimes DT. Antagonistic interactions in the zebrafish midline prior to the emergence of asymmetric gene expression are important for left-right patterning. Philos Trans R Soc Lond B Biol Sci 2017; 371:rstb.2015.0402. [PMID: 27821532 DOI: 10.1098/rstb.2015.0402] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/12/2016] [Indexed: 12/16/2022] Open
Abstract
Left-right (L-R) asymmetry of the internal organs of vertebrates is presaged by domains of asymmetric gene expression in the lateral plate mesoderm (LPM) during somitogenesis. Ciliated L-R coordinators (LRCs) are critical for biasing the initiation of asymmetrically expressed genes, such as nodal and pitx2, to the left LPM. Other midline structures, including the notochord and floorplate, are then required to maintain these asymmetries. Here we report an unexpected role for the zebrafish EGF-CFC gene one-eyed pinhead (oep) in the midline to promote pitx2 expression in the LPM. Late zygotic oep (LZoep) mutants have strongly reduced or absent pitx2 expression in the LPM, but this expression can be rescued to strong levels by restoring oep in midline structures only. Furthermore, removing midline structures from LZoep embryos can rescue pitx2 expression in the LPM, suggesting the midline is a source of an LPM pitx2 repressor that is itself inhibited by oep Reducing lefty1 activity in LZoep embryos mimics removal of the midline, implicating lefty1 in the midline-derived repression. Together, this suggests a model where Oep in the midline functions to overcome a midline-derived repressor, involving lefty1, to allow for the expression of left side-specific genes in the LPM.This article is part of the themed issue 'Provocative questions in left-right asymmetry'.
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Affiliation(s)
- Rebecca D Burdine
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
| | - Daniel T Grimes
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
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79
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Wan LQ, Chin AS, Worley KE, Ray P. Cell chirality: emergence of asymmetry from cell culture. Philos Trans R Soc Lond B Biol Sci 2017; 371:rstb.2015.0413. [PMID: 27821525 DOI: 10.1098/rstb.2015.0413] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/22/2016] [Indexed: 11/12/2022] Open
Abstract
Increasing evidence suggests that intrinsic cell chirality significantly contributes to the left-right (LR) asymmetry in embryonic development, which is a well-conserved characteristic of living organisms. With animal embryos, several theories have been established, but there are still controversies regarding mechanisms associated with embryonic LR symmetry breaking and the formation of asymmetric internal organs. Recently, in vitro systems have been developed to determine cell chirality and to recapitulate multicellular chiral morphogenesis on a chip. These studies demonstrate that chirality is indeed a universal property of the cell that can be observed with well-controlled experiments such as micropatterning. In this paper, we discuss the possible benefits of these in vitro systems to research in LR asymmetry, categorize available platforms for single-cell chirality and multicellular chiral morphogenesis, and review mathematical models used for in vitro cell chirality and its applications in in vivo embryonic development. These recent developments enable the interrogation of the intracellular machinery in LR axis establishment and accelerate research in birth defects in laterality.This article is part of the themed issue 'Provocative questions in left-right asymmetry'.
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Affiliation(s)
- Leo Q Wan
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY 12180, USA .,Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY 12180, USA.,Center for Modeling, Simulation and Imaging in Medicine, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY 12180, USA
| | - Amanda S Chin
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY 12180, USA
| | - Kathryn E Worley
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY 12180, USA
| | - Poulomi Ray
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY 12180, USA.,Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY 12180, USA
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80
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Factors Affecting the Perception of 3D Facial Symmetry from 2D Projections. Symmetry (Basel) 2017. [DOI: 10.3390/sym9100243] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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81
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Pai VP, Willocq V, Pitcairn EJ, Lemire JM, Paré JF, Shi NQ, McLaughlin KA, Levin M. HCN4 ion channel function is required for early events that regulate anatomical left-right patterning in a nodal and lefty asymmetric gene expression-independent manner. Biol Open 2017; 6:1445-1457. [PMID: 28818840 PMCID: PMC5665463 DOI: 10.1242/bio.025957] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Accepted: 08/12/2017] [Indexed: 12/13/2022] Open
Abstract
Laterality is a basic characteristic of all life forms, from single cell organisms to complex plants and animals. For many metazoans, consistent left-right asymmetric patterning is essential for the correct anatomy of internal organs, such as the heart, gut, and brain; disruption of left-right asymmetry patterning leads to an important class of birth defects in human patients. Laterality functions across multiple scales, where early embryonic, subcellular and chiral cytoskeletal events are coupled with asymmetric amplification mechanisms and gene regulatory networks leading to asymmetric physical forces that ultimately result in distinct left and right anatomical organ patterning. Recent studies have suggested the existence of multiple parallel pathways regulating organ asymmetry. Here, we show that an isoform of the hyperpolarization-activated cyclic nucleotide-gated (HCN) family of ion channels (hyperpolarization-activated cyclic nucleotide-gated channel 4, HCN4) is important for correct left-right patterning. HCN4 channels are present very early in Xenopus embryos. Blocking HCN channels (Ih currents) with pharmacological inhibitors leads to errors in organ situs. This effect is only seen when HCN4 channels are blocked early (pre-stage 10) and not by a later block (post-stage 10). Injections of HCN4-DN (dominant-negative) mRNA induce left-right defects only when injected in both blastomeres no later than the 2-cell stage. Analysis of key asymmetric genes' expression showed that the sidedness of Nodal, Lefty, and Pitx2 expression is largely unchanged by HCN4 blockade, despite the randomization of subsequent organ situs, although the area of Pitx2 expression was significantly reduced. Together these data identify a novel, developmental role for HCN4 channels and reveal a new Nodal-Lefty-Pitx2 asymmetric gene expression-independent mechanism upstream of organ positioning during embryonic left-right patterning.
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Affiliation(s)
- Vaibhav P Pai
- Allen Discovery Center at Tufts University, 200 Boston Ave, Suite 4600, Medford, MA 02155, USA
| | - Valerie Willocq
- Allen Discovery Center at Tufts University, 200 Boston Ave, Suite 4600, Medford, MA 02155, USA
| | - Emily J Pitcairn
- Allen Discovery Center at Tufts University, 200 Boston Ave, Suite 4600, Medford, MA 02155, USA
| | - Joan M Lemire
- Allen Discovery Center at Tufts University, 200 Boston Ave, Suite 4600, Medford, MA 02155, USA
| | - Jean-François Paré
- Allen Discovery Center at Tufts University, 200 Boston Ave, Suite 4600, Medford, MA 02155, USA
| | - Nian-Qing Shi
- Department of Medicine at University of Wisconsin-Madison, Madison, WI 53792, USA
| | - Kelly A McLaughlin
- Allen Discovery Center at Tufts University, 200 Boston Ave, Suite 4600, Medford, MA 02155, USA
| | - Michael Levin
- Allen Discovery Center at Tufts University, 200 Boston Ave, Suite 4600, Medford, MA 02155, USA
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82
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Sadler TW. Establishing the Embryonic Axes: Prime Time for Teratogenic Insults. J Cardiovasc Dev Dis 2017; 4:E15. [PMID: 29367544 PMCID: PMC5715709 DOI: 10.3390/jcdd4030015] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 09/01/2017] [Accepted: 09/02/2017] [Indexed: 01/21/2023] Open
Abstract
A long standing axiom in the field of teratology states that the teratogenic period, when most birth defects are produced, occurs during the third to eighth weeks of development post-fertilization. Any insults prior to this time are thought to result in a slowing of embryonic growth from which the conceptus recovers or death of the embryo followed by spontaneous abortion. However, new insights into embryonic development during the first two weeks, including formation of the anterior-posterior, dorsal-ventral, and left-right axes, suggests that signaling pathways regulating these processes are prime targets for genetic and toxic insults. Establishment of the left-right (laterality) axis is particularly sensitive to disruption at very early stages of development and these perturbations result in a wide variety of congenital malformations, especially heart defects. Thus, the time for teratogenic insults resulting in birth defects should be reset to include the first two weeks of development.
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Affiliation(s)
- Thomas W Sadler
- Senior Fellow, Greenwood Genetics Center, Greenwood, SC 29646, USA.
- Department of Pediatrics, University of Utah, Salt Lake City, UT 84108, USA.
- Department of Anatomy, Quillen College of Medicine, East Tennessee State University, Johnson, TN 37614, USA.
- 78 Lemon Gulch Lane, Sheridan, MT 59749, USA.
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83
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Besson M, Gache C, Bertucci F, Brooker RM, Roux N, Jacob H, Berthe C, Sovrano VA, Dixson DL, Lecchini D. Exposure to agricultural pesticide impairs visual lateralization in a larval coral reef fish. Sci Rep 2017; 7:9165. [PMID: 28831109 PMCID: PMC5567261 DOI: 10.1038/s41598-017-09381-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 07/26/2017] [Indexed: 12/31/2022] Open
Abstract
Lateralization, i.e. the preferential use of one side of the body, may convey fitness benefits for organisms within rapidly-changing environments, by optimizing separate and parallel processing of different information between the two brain hemispheres. In coral reef-fishes, the movement of larvae from planktonic to reef environments (recruitment) represents a major life-history transition. This transition requires larvae to rapidly identify and respond to sensory cues to select a suitable habitat that facilitates survival and growth. This 'recruitment' is critical for population persistence and resilience. In aquarium experiments, larval Acanthurus triostegus preferentially used their right-eye to investigate a variety of visual stimuli. Despite this, when held in in situ cages with predators, those larvae that previously favored their left-eye exhibited higher survival. These results support the "brain's right-hemisphere" theory, which predicts that the right-eye (i.e. left-hemisphere) is used to categorize stimuli while the left-eye (i.e. right-hemisphere) is used to inspect novel items and initiate rapid behavioral-responses. While these experiments confirm that being highly lateralized is ecologically advantageous, exposure to chlorpyrifos, a pesticide often inadvertently added to coral-reef waters, impaired visual-lateralization. This suggests that chemical pollutants could impair the brain function of larval fishes during a critical life-history transition, potentially impacting recruitment success.
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Affiliation(s)
- Marc Besson
- PSL Research University: EPHE-UPVD-CNRS, USR 3278 CRIOBE, BP 1013, 98729, Papetoai, Moorea, French Polynesia.
- Université Pierre et Marie Curie, UMR CNRS 7232 OOB, 1 Avenue Pierre Fabre, 66650, Banyuls-sur-Mer, France.
| | - Camille Gache
- PSL Research University: EPHE-UPVD-CNRS, USR 3278 CRIOBE, BP 1013, 98729, Papetoai, Moorea, French Polynesia
- Laboratoire d'Excellence "CORAIL", BP 1013, 98729, Papetoai, Moorea, French Polynesia
| | - Frédéric Bertucci
- PSL Research University: EPHE-UPVD-CNRS, USR 3278 CRIOBE, BP 1013, 98729, Papetoai, Moorea, French Polynesia
- Laboratoire de Morphologie Fonctionnelle et Evolutive, AFFISH Research Center, Institut de Chimie B6c, Université de Liège, Liège, Belgium
| | - Rohan M Brooker
- School of Marine Science and policy, University of Delaware, 111 Robinson Hall, Newark, DE, 19716, USA
| | - Natacha Roux
- PSL Research University: EPHE-UPVD-CNRS, USR 3278 CRIOBE, BP 1013, 98729, Papetoai, Moorea, French Polynesia
- Université Pierre et Marie Curie, UMR CNRS 7232 OOB, 1 Avenue Pierre Fabre, 66650, Banyuls-sur-Mer, France
| | - Hugo Jacob
- PSL Research University: EPHE-UPVD-CNRS, USR 3278 CRIOBE, BP 1013, 98729, Papetoai, Moorea, French Polynesia
- International Atomic Energy Agency, Environment Laboratories (IAEA-EL), Principality of Monaco, 98000, Monaco
| | - Cécile Berthe
- PSL Research University: EPHE-UPVD-CNRS, USR 3278 CRIOBE, BP 1013, 98729, Papetoai, Moorea, French Polynesia
- Laboratoire d'Excellence "CORAIL", BP 1013, 98729, Papetoai, Moorea, French Polynesia
| | - Valeria Anna Sovrano
- Center for Mind/Brain Sciences (CIMeC), University of Trento, Piazza Manifattura 1, 38068, Rovereto (TN), Italy
| | - Danielle L Dixson
- School of Marine Science and policy, University of Delaware, 111 Robinson Hall, Newark, DE, 19716, USA
| | - David Lecchini
- PSL Research University: EPHE-UPVD-CNRS, USR 3278 CRIOBE, BP 1013, 98729, Papetoai, Moorea, French Polynesia
- Laboratoire d'Excellence "CORAIL", BP 1013, 98729, Papetoai, Moorea, French Polynesia
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84
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Casanova EL. Links Between Patterns of Embryonic Spinal Cord Development and Schizophrenia Risk. Biol Psychiatry 2017; 82:e21-e22. [PMID: 28693739 DOI: 10.1016/j.biopsych.2017.05.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Accepted: 05/03/2017] [Indexed: 10/19/2022]
Affiliation(s)
- Emily L Casanova
- Department of Biomedical Sciences, University of South Carolina Medical School at Greenville, Greenville, South Carolina.
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85
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Ferreira RR, Vilfan A, Jülicher F, Supatto W, Vermot J. Physical limits of flow sensing in the left-right organizer. eLife 2017; 6. [PMID: 28613157 PMCID: PMC5544429 DOI: 10.7554/elife.25078] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 06/13/2017] [Indexed: 12/20/2022] Open
Abstract
Fluid flows generated by motile cilia are guiding the establishment of the left-right asymmetry of the body in the vertebrate left-right organizer. Competing hypotheses have been proposed: the direction of flow is sensed either through mechanosensation, or via the detection of chemical signals transported in the flow. We investigated the physical limits of flow detection to clarify which mechanisms could be reliably used for symmetry breaking. We integrated parameters describing cilia distribution and orientation obtained in vivo in zebrafish into a multiscale physical study of flow generation and detection. Our results show that the number of immotile cilia is too small to ensure robust left and right determination by mechanosensing, given the large spatial variability of the flow. However, motile cilia could sense their own motion by a yet unknown mechanism. Finally, transport of chemical signals by the flow can provide a simple and reliable mechanism of asymmetry establishment. DOI:http://dx.doi.org/10.7554/eLife.25078.001
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Affiliation(s)
- Rita R Ferreira
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France.,Centre National de la Recherche Scientifique, Illkirch, France.,Institut National de la Santé et de la Recherche Médicale, Illkirch, France.,Université de Strasbourg, Illkirch, France
| | | | - Frank Jülicher
- Max-Planck-Institute for the Physics of Complex Systems, Dresden, Germany
| | - Willy Supatto
- Laboratory for Optics and Biosciences, Ecole Polytechnique, Centre National de la Recherche Scientifique (UMR7645), Institut National de la Santé et de la Recherche Médicale (U1182) and Paris Saclay University, Palaiseau, France
| | - Julien Vermot
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France.,Centre National de la Recherche Scientifique, Illkirch, France.,Institut National de la Santé et de la Recherche Médicale, Illkirch, France.,Université de Strasbourg, Illkirch, France
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86
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Androgen Levels and Body Size Are Associated with Directional as Well as Fluctuating Asymmetry Patterns in Adult !Kung San and Kavango Males from Northern Namibia. Symmetry (Basel) 2017. [DOI: 10.3390/sym9050072] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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87
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Lateral thinking - Interocular symmetry and asymmetry in neurovascular patterning, in health and disease. Prog Retin Eye Res 2017; 59:131-157. [PMID: 28457789 DOI: 10.1016/j.preteyeres.2017.04.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Revised: 03/24/2017] [Accepted: 04/24/2017] [Indexed: 02/07/2023]
Abstract
No biological system or structure is likely to be perfectly symmetrical, or have identical right and left forms. This review explores the evidence for eye and visual pathway asymmetry, in health and in disease, and attempts to provide guidance for those studying the structure and function of the visual system, where recognition of symmetry or asymmetry may be essential. The principal question with regards to asymmetry is not 'are the eyes the same?', for some degree of asymmetry is pervasive, but 'when are they importantly different?'. Knowing if right and left eyes are 'importantly different' could have significant consequences for deciding whether right or left eyes are included in an analysis or for examining the association between a phenotype and ocular parameter. The presence of significant asymmetry would also have important implications for the design of normative databases of retinal and optic nerve metrics. In this review, we highlight not only the universal presence of asymmetry, but provide evidence that some elements of the visual system are inherently more asymmetric than others, pointing to the need for improved normative data to explain sources of asymmetry and their impact on determining associations with genetic, environmental or health-related factors and ultimately in clinical practice.
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88
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Catana A, Apostu AP. The determination factors of left-right asymmetry disorders- a short review. ACTA ACUST UNITED AC 2017; 90:139-146. [PMID: 28559696 PMCID: PMC5433564 DOI: 10.15386/cjmed-701] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 10/02/2016] [Accepted: 11/23/2016] [Indexed: 12/17/2022]
Abstract
Laterality defects in humans, situs inversus and heterotaxy, are rare disorders, with an incidence of 1:8000 to 1:10 000 in the general population, and a multifactorial etiology. It has been proved that 1.44/10 000 of all cardiac problems are associated with malformations of left-right asymmetry and heterotaxy accounts for 3% of all congenital heart defects. It is considered that defects of situs appear due to genetic and environmental factors. Also, there is evidence that the ciliopathies (defects of structure or function) are involved in development abnormalities. Over 100 genes have been reported to be involved in left-right patterning in model organisms, but only a few are likely to candidate for left-right asymmetry defects in humans. Left-right asymmetry disorders are genetically heterogeneous and have variable manifestations (from asymptomatic to serious clinical problems). The discovery of the right mechanism of left-right development will help explain the clinical complexity and may contribute to a therapy of these disorders.
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Affiliation(s)
- Andreea Catana
- Genetics Department, Iuliu Hatieganu University of Medicine and Pharmacy, Cluj-Napoca, Romania
| | - Adina Patricia Apostu
- Genetics Department, Iuliu Hatieganu University of Medicine and Pharmacy, Cluj-Napoca, Romania
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89
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Leung C, Duclos KK, Grünbaum T, Cloutier R, Angers B. Asymmetry in dentition and shape of pharyngeal arches in the clonal fish Chrosomus eos-neogaeus: Phenotypic plasticity and developmental instability. PLoS One 2017; 12:e0174235. [PMID: 28380079 PMCID: PMC5381790 DOI: 10.1371/journal.pone.0174235] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 03/06/2017] [Indexed: 01/15/2023] Open
Abstract
The effect of the environment may result in different developmental outcomes. Extrinsic signals can modify developmental pathways and result in alternative phenotypes (phenotypic plasticity). The environment can also be interpreted as a stressor and increase developmental instability (developmental noise). Directional and fluctuating asymmetry provide a conceptual background to discriminate between these results. This study aims at assessing whether variation in dentition and shape of pharyngeal arches of the clonal fish Chrosomus eos-neogaeus results from developmental instability or environmentally induced changes. A total of 262 specimens of the Chrosomus eos-neogaeus complex from 12 natural sites were analysed. X-ray microcomputed tomography (X-ray micro-CT) was used to visualize the pharyngeal arches in situ with high resolution. Variation in the number of pharyngeal teeth is high in hybrids in contrast to the relative stability observed in both parental species. The basal dental formula is symmetric while the most frequent alternative dental formula is asymmetric. Within one lineage, large variation in the proportion of individuals bearing basal or alternative dental formulae was observed among sites in the absence of genetic difference. Both dentition and arch shape of this hybrid lineage were explained significantly by environmental differences. Only individuals bearing asymmetric dental formula displayed fluctuating asymmetry as well as directional left-right asymmetry for the arches. The hybrids appeared sensitive to environmental signals and intraspecific variation on pharyngeal teeth was not random but reflects phenotypic plasticity. Altogether, these results support the influence of the environment as a trigger for an alternative developmental pathway resulting in left-right asymmetry in dentition and shape of pharyngeal arches.
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Affiliation(s)
- Christelle Leung
- Department of Biological Sciences, Université de Montréal, Montreal, Quebec, Canada
| | - Kevin Karl Duclos
- Department of Biological Sciences, Université de Montréal, Montreal, Quebec, Canada
| | - Thomas Grünbaum
- Department of Biological Sciences, Université de Montréal, Montreal, Quebec, Canada
| | - Richard Cloutier
- Département de Biologie, Chimie et Géographie, Université du Québec à Rimouski, Rimouski, Quebec, Canada
| | - Bernard Angers
- Department of Biological Sciences, Université de Montréal, Montreal, Quebec, Canada
- * E-mail:
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90
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Ferreira RR, Vermot J. The balancing roles of mechanical forces during left-right patterning and asymmetric morphogenesis. Mech Dev 2017; 144:71-80. [DOI: 10.1016/j.mod.2016.11.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 11/03/2016] [Indexed: 11/17/2022]
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91
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Sathiyadevi K, Karthiga S, Chandrasekar VK, Senthilkumar DV, Lakshmanan M. Spontaneous symmetry breaking due to the trade-off between attractive and repulsive couplings. Phys Rev E 2017; 95:042301. [PMID: 28505842 DOI: 10.1103/physreve.95.042301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Indexed: 06/07/2023]
Abstract
Spontaneous symmetry breaking is an important phenomenon observed in various fields including physics and biology. In this connection, we here show that the trade-off between attractive and repulsive couplings can induce spontaneous symmetry breaking in a homogeneous system of coupled oscillators. With a simple model of a system of two coupled Stuart-Landau oscillators, we demonstrate how the tendency of attractive coupling in inducing in-phase synchronized (IPS) oscillations and the tendency of repulsive coupling in inducing out-of-phase synchronized oscillations compete with each other and give rise to symmetry breaking oscillatory states and interesting multistabilities. Further, we provide explicit expressions for synchronized and antisynchronized oscillatory states as well as the so called oscillation death (OD) state and study their stability. If the Hopf bifurcation parameter (λ) is greater than the natural frequency (ω) of the system, the attractive coupling favors the emergence of an antisymmetric OD state via a Hopf bifurcation whereas the repulsive coupling favors the emergence of a similar state through a saddle-node bifurcation. We show that an increase in the repulsive coupling not only destabilizes the IPS state but also facilitates the reentrance of the IPS state.
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Affiliation(s)
- K Sathiyadevi
- Centre for Nonlinear Science & Engineering, School of Electrical & Electronics Engineering, SASTRA University, Thanjavur 613 401, Tamil Nadu, India
| | - S Karthiga
- Centre for Nonlinear Dynamics, School of Physics, Bharathidasan University, Tiruchirappalli 620 024, Tamil Nadu, India
| | - V K Chandrasekar
- Centre for Nonlinear Science & Engineering, School of Electrical & Electronics Engineering, SASTRA University, Thanjavur 613 401, Tamil Nadu, India
| | - D V Senthilkumar
- School of Physics, Indian Institute of Science Education and Research, Thiruvananthapuram 695 016, India
| | - M Lakshmanan
- Centre for Nonlinear Dynamics, School of Physics, Bharathidasan University, Tiruchirappalli 620 024, Tamil Nadu, India
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92
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Luxenburg C, Geiger B. Multiscale View of Cytoskeletal Mechanoregulation of Cell and Tissue Polarity. Handb Exp Pharmacol 2017; 235:263-284. [PMID: 27807694 DOI: 10.1007/164_2016_34] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The ability of cells to generate, maintain, and repair tissues with complex architecture, in which distinct cells function as coherent units, relies on polarity cues. Polarity can be described as an asymmetry along a defined axis, manifested at the molecular, structural, and functional levels. Several types of cell and tissue polarities were described in the literature, including front-back, apical-basal, anterior-posterior, and left-right polarity. Extensive research provided insights into the specific regulators of each polarization process, as well as into generic elements that affect all types of polarities. The actin cytoskeleton and the associated adhesion structures are major regulators of most, if not all, known forms of polarity. Actin filaments exhibit intrinsic polarity and their ability to bind many proteins including the mechanosensitive adhesion and motor proteins, such as myosins, play key roles in cell polarization. The actin cytoskeleton can generate mechanical forces and together with the associated adhesions, probe the mechanical, structural, and chemical properties of the environment, and transmit signals that impact numerous biological processes, including cell polarity. In this article we highlight novel mechanisms whereby the mechanical forces and actin-adhesion complexes regulate cell and tissue polarity in a variety of natural and experimental systems.
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Affiliation(s)
- Chen Luxenburg
- Department of Cell and Developmental Biology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, 69978, Israel.
| | - Benjamin Geiger
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, 76100, Israel.
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93
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Egan PJ, Mitrovics TC, Tomandl BF. Alternate ventricular asymmetry could suggest a psychiatric diagnosis. Clin Anat 2016; 30:50-52. [PMID: 27599380 DOI: 10.1002/ca.22789] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 08/31/2016] [Accepted: 08/31/2016] [Indexed: 11/12/2022]
Abstract
Routine magnetic resonance imaging (MRI) of the skull and brain for diagnostic purposes sometimes reveals a wider tip of the frontal ventricular horn on one side and a wider tip of the temporal horn on the other. A search for 'alternate ventricular asymmetry' in Google Scholar, Medline and PubMed Central yielded no results, so the digital archive of the hospital was searched for such cases. A total of 5908 examinations were reviewed and 508 cases were found, comprising 6% of the neurological inpatients and 20% of the psychiatric inpatients (P = 0.001 by χ2 ). The >3-fold difference in the incidence of this particular ventricular asymmetry implies that it could suggest a psychiatric diagnosis. Clin. Anat. 30:50-52, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- P J Egan
- Klinik für Radiologie und Neuroradiologie, Christophsbad GmbH &Co Fachkrankenhaus KG, Faurndauer Straße 6 - 28, Göppingen, 73035
| | - T C Mitrovics
- Klinik für Radiologie und Neuroradiologie, Christophsbad GmbH &Co Fachkrankenhaus KG, Faurndauer Straße 6 - 28, Göppingen, 73035
| | - B F Tomandl
- Klinik für Radiologie und Neuroradiologie, Christophsbad GmbH &Co Fachkrankenhaus KG, Faurndauer Straße 6 - 28, Göppingen, 73035
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94
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Diaphanous gene mutation affects spiral cleavage and chirality in snails. Sci Rep 2016; 6:34809. [PMID: 27708420 PMCID: PMC5052593 DOI: 10.1038/srep34809] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Accepted: 09/16/2016] [Indexed: 11/09/2022] Open
Abstract
L-R (left and right) symmetry breaking during embryogenesis and the establishment of asymmetric body plan are key issues in developmental biology, but the onset including the handedness-determining gene locus still remains unknown. Using pure dextral (DD) and sinistral (dd) strains of the pond snail Lymnaea stagnalis as well as its F2 through to F10 backcrossed lines, the single handedness-determining-gene locus was mapped by genetic linkage analysis, BAC cloning and chromosome walking. We have identified the actin-related diaphanous gene Lsdia1 as the strongest candidate. Although the cDNA and derived amino acid sequences of the tandemly duplicated Lsdia1 and Lsdia2 genes are very similar, we could discriminate the two genes/proteins in our molecular biology experiments. The Lsdia1 gene of the sinistral strain carries a frameshift mutation that abrogates full-length LsDia1 protein expression. In the dextral strain, it is already translated prior to oviposition. Expression of Lsdia1 (only in the dextral strain) and Lsdia2 (in both chirality) decreases after the 1-cell stage, with no asymmetric localization throughout. The evolutionary relationships among body handedness, SD/SI (spiral deformation/spindle inclination) at the third cleavage, and expression of diaphanous proteins are discussed in comparison with three other pond snails (L. peregra, Physa acuta and Indoplanorbis exustus).
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95
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Kirchengast S. Directional and fluctuating asymmetry among !Kung San and Kavango people of Northern Namibia: The impact of sex and subsistence patterns. Am J Hum Biol 2016; 29. [DOI: 10.1002/ajhb.22921] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 08/20/2016] [Indexed: 11/10/2022] Open
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96
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Raymond MJ, Ray P, Kaur G, Fredericks M, Singh AV, Wan LQ. Multiaxial Polarity Determines Individual Cellular and Nuclear Chirality. Cell Mol Bioeng 2016; 10:63-74. [PMID: 28360944 DOI: 10.1007/s12195-016-0467-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Intrinsic cell chirality has been implicated in the left-right (LR) asymmetry of embryonic development. Impaired cell chirality could lead to severe birth defects in laterality. Previously, we detected cell chirality with an in vitro micropatterning system. Here, we demonstrate for the first time that chirality can be quantified as the coordination of multiaxial polarization of individual cells and nuclei. Using an object labeling, connected component based method, we characterized cell chirality based on cell and nuclear shape polarization and nuclear positioning of each cell in multicellular patterns of epithelial cells. We found that the cells adopted a LR bias the boundaries by positioning the sharp end towards the leading edge and leaving the nucleus at the rear. This behavior is consistent with the directional migration observed previously on the boundary of micropatterns. Although the nucleus is chirally aligned, it is not strongly biased towards or away from the boundary. As the result of the rear positioning of nuclei, the nuclear positioning has an opposite chirality to that of cell alignment. Overall, our results have revealed deep insights of chiral morphogenesis as the coordination of multiaxial polarization at the cellular and subcellular levels.
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Affiliation(s)
- Michael J Raymond
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy NY 12180
| | - Poulomi Ray
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy NY 12180; Center for Biotechnology & Interdisciplinary Studies, Rensselaer Polytechnic Institute, 110 8th Street, Troy NY 12180
| | - Gurleen Kaur
- Department of Biology, Rensselaer Polytechnic Institute, 110 8th Street, Troy NY 12180
| | - Michael Fredericks
- Department of Computer Science, Rensselaer Polytechnic Institute, 110 8th Street, Troy NY 12180
| | - Ajay V Singh
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy NY 12180; Center for Biotechnology & Interdisciplinary Studies, Rensselaer Polytechnic Institute, 110 8th Street, Troy NY 12180
| | - Leo Q Wan
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy NY 12180; Center for Biotechnology & Interdisciplinary Studies, Rensselaer Polytechnic Institute, 110 8th Street, Troy NY 12180; Center for Modeling, Simulation and Imaging in Medicine, Rensselaer Polytechnic Institute, 110 8th Street, Troy NY 12180
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97
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Raffini F, Fruciano C, Franchini P, Meyer A. Towards understanding the genetic basis of mouth asymmetry in the scale-eating cichlidPerissodus microlepis. Mol Ecol 2016; 26:77-91. [DOI: 10.1111/mec.13699] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Revised: 04/29/2016] [Accepted: 05/09/2016] [Indexed: 12/16/2022]
Affiliation(s)
- Francesca Raffini
- Lehrstuhl für Zoologie und Evolutionsbiologie; Department of Biology; University of Konstanz; Universitätsstrasse 10 78464 Konstanz Germany
- International Max Planck Research School (IMPRS) for Organismal Biology; Max-Planck-Institut für Ornithologie; Am Obstberg 1 78315 Radolfzell Germany
| | - Carmelo Fruciano
- Lehrstuhl für Zoologie und Evolutionsbiologie; Department of Biology; University of Konstanz; Universitätsstrasse 10 78464 Konstanz Germany
| | - Paolo Franchini
- Lehrstuhl für Zoologie und Evolutionsbiologie; Department of Biology; University of Konstanz; Universitätsstrasse 10 78464 Konstanz Germany
| | - Axel Meyer
- Lehrstuhl für Zoologie und Evolutionsbiologie; Department of Biology; University of Konstanz; Universitätsstrasse 10 78464 Konstanz Germany
- International Max Planck Research School (IMPRS) for Organismal Biology; Max-Planck-Institut für Ornithologie; Am Obstberg 1 78315 Radolfzell Germany
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98
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Loganathan R, Rongish BJ, Smith CM, Filla MB, Czirok A, Bénazéraf B, Little CD. Extracellular matrix motion and early morphogenesis. Development 2016; 143:2056-65. [PMID: 27302396 PMCID: PMC4920166 DOI: 10.1242/dev.127886] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
For over a century, embryologists who studied cellular motion in early amniotes generally assumed that morphogenetic movement reflected migration relative to a static extracellular matrix (ECM) scaffold. However, as we discuss in this Review, recent investigations reveal that the ECM is also moving during morphogenesis. Time-lapse studies show how convective tissue displacement patterns, as visualized by ECM markers, contribute to morphogenesis and organogenesis. Computational image analysis distinguishes between cell-autonomous (active) displacements and convection caused by large-scale (composite) tissue movements. Modern quantification of large-scale 'total' cellular motion and the accompanying ECM motion in the embryo demonstrates that a dynamic ECM is required for generation of the emergent motion patterns that drive amniote morphogenesis.
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Affiliation(s)
- Rajprasad Loganathan
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Brenda J Rongish
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, KS 66160, USA
| | - Christopher M Smith
- Department of Anatomy, Howard University College of Medicine, Washington, DC 20059, USA
| | - Michael B Filla
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, KS 66160, USA
| | - Andras Czirok
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, KS 66160, USA Department of Biological Physics, Eotvos University, Budapest 1117, Hungary
| | - Bertrand Bénazéraf
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), CNRS (UMR 7104), Inserm U964, Université de Strasbourg, Illkirch Graffenstaden 67400, France
| | - Charles D Little
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, KS 66160, USA
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99
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Abstract
The endoderm is the innermost embryonic germ layer, and in zebrafish, it gives rise to the lining of the gut, the gills, liver, pancreas, gallbladder, and derivatives of the pharyngeal pouch. These organs form the gastrointestinal tract and are involved with the absorption, delivery, and metabolism of nutrients. The liver has a central role in regulating these processes because it controls carbohydrate and lipid metabolism, protein synthesis, and breakdown of endogenous and xenobiotic products. Liver dysfunction frequently leads to significant morbidity and mortality; however, in most settings of organ injury, the liver exhibits remarkable regenerative capacity. In this chapter, we review the principal mechanisms of endoderm and liver formation and provide protocols to assess liver formation and liver regeneration.
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100
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Chen D, Zhong Y. A computational model of dynein activation patterns that can explain nodal cilia rotation. Biophys J 2016; 109:35-48. [PMID: 26153700 DOI: 10.1016/j.bpj.2015.05.027] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Revised: 05/03/2015] [Accepted: 05/18/2015] [Indexed: 10/23/2022] Open
Abstract
Normal left-right patterning in vertebrates depends on the rotational movement of nodal cilia. In order to produce this ciliary motion, the activity of axonemal dyneins must be tightly regulated in a temporal and spatial manner; the specific activation pattern of the dynein motors in the nodal cilia has not been reported. Contemporary imaging techniques cannot directly assess dynein activity in a living cilium. In this study, we establish a three-dimensional model to mimic the ciliary ultrastructure and assume that the activation of dynein proteins is related to the interdoublet distance. By employing finite-element analysis and grid deformation techniques, we simulate the mechanical function of dyneins by pairs of point loads, investigate the time-variant interdoublet distance, and simulate the dynein-triggered ciliary motion. The computational results indicate that, to produce the rotational movement of nodal cilia, the dynein activity is transferred clockwise (looking from the tip) between the nine doublet microtubules, and along each microtubule, the dynein activation should occur faster at the basal region and slower when it is close to the ciliary tip. Moreover, the time cost by all the dyneins along one microtubule to be activated can be used to deduce the dynein activation pattern; it implies that, as an alternative method, measuring this time can indirectly reveal the dynein activity. The proposed protein-structure model can simulate the ciliary motion triggered by various dynein activation patterns explicitly and may contribute to furthering the studies on axonemal dynein activity.
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Affiliation(s)
- Duanduan Chen
- School of Life Science, Beijing Institute of Technology, Beijing, China.
| | - Yi Zhong
- School of Life Science, Beijing Institute of Technology, Beijing, China
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