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Frank ET, Kesner L, Liberti J, Helleu Q, LeBoeuf AC, Dascalu A, Sponsler DB, Azuma F, Economo EP, Waridel P, Engel P, Schmitt T, Keller L. Targeted treatment of injured nestmates with antimicrobial compounds in an ant society. Nat Commun 2023; 14:8446. [PMID: 38158416 PMCID: PMC10756881 DOI: 10.1038/s41467-023-43885-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Accepted: 11/20/2023] [Indexed: 01/03/2024] Open
Abstract
Infected wounds pose a major mortality risk in animals. Injuries are common in the ant Megaponera analis, which raids pugnacious prey. Here we show that M. analis can determine when wounds are infected and treat them accordingly. By applying a variety of antimicrobial compounds and proteins secreted from the metapleural gland to infected wounds, workers reduce the mortality of infected individuals by 90%. Chemical analyses showed that wound infection is associated with specific changes in the cuticular hydrocarbon profile, thereby likely allowing nestmates to diagnose the infection state of injured individuals and apply the appropriate antimicrobial treatment. This study demonstrates that M. analis ant societies use antimicrobial compounds produced in the metapleural glands to treat infected wounds and reduce nestmate mortality.
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Affiliation(s)
- Erik T Frank
- Department of Ecology and Evolution, Biophore, University of Lausanne, CH-1015, Lausanne, Switzerland.
- Department of Animal Ecology and Tropical Biology, Biocenter, University of Würzburg, D-97074, Würzburg, Germany.
| | - Lucie Kesner
- Department of Fundamental Microbiology, Biophore, University of Lausanne, CH-1015, Lausanne, Switzerland
| | - Joanito Liberti
- Department of Ecology and Evolution, Biophore, University of Lausanne, CH-1015, Lausanne, Switzerland
- Department of Fundamental Microbiology, Biophore, University of Lausanne, CH-1015, Lausanne, Switzerland
| | - Quentin Helleu
- Department of Ecology and Evolution, Biophore, University of Lausanne, CH-1015, Lausanne, Switzerland
- Structure et Instabilité des Génomes, Muséum National d'Histoire Naturelle, CNRS UMR 7196, INSERM U1154, 43 rue Cuvier, F-75005, Paris, France
| | - Adria C LeBoeuf
- Department of Biology, University of Fribourg, CH-1700, Fribourg, Switzerland
| | - Andrei Dascalu
- Department of Ecology and Evolution, Biophore, University of Lausanne, CH-1015, Lausanne, Switzerland
| | - Douglas B Sponsler
- Department of Animal Ecology and Tropical Biology, Biocenter, University of Würzburg, D-97074, Würzburg, Germany
| | - Fumika Azuma
- Biodiversity and Biocomplexity Unit, Okinawa Institute of Science and Technology Graduate University, Onna, 904-0495, Japan
| | - Evan P Economo
- Biodiversity and Biocomplexity Unit, Okinawa Institute of Science and Technology Graduate University, Onna, 904-0495, Japan
- Radcliffe Institute for Advanced Study, Harvard University, Cambridge, 02138, USA
| | - Patrice Waridel
- Protein Analysis Facility, Génopode, University of Lausanne, CH-1015, Lausanne, Switzerland
| | - Philipp Engel
- Department of Fundamental Microbiology, Biophore, University of Lausanne, CH-1015, Lausanne, Switzerland
| | - Thomas Schmitt
- Department of Animal Ecology and Tropical Biology, Biocenter, University of Würzburg, D-97074, Würzburg, Germany
| | - Laurent Keller
- Department of Ecology and Evolution, Biophore, University of Lausanne, CH-1015, Lausanne, Switzerland.
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2
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Negroni MA, LeBoeuf AC. Social administration of juvenile hormone to larvae increases body size and nutritional needs for pupation. R Soc Open Sci 2023; 10:231471. [PMID: 38126067 PMCID: PMC10731321 DOI: 10.1098/rsos.231471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Accepted: 11/28/2023] [Indexed: 12/23/2023]
Abstract
Social insects often display extreme variation in body size and morphology within the same colony. In many species, adult morphology is socially regulated by workers during larval development. While larval nutrition may play a role in this regulation, it is often difficult to identify precisely what larvae receive from rearing workers, especially when larvae are fed through social regurgitation. Across insects, juvenile hormone is a major regulator of development. In the ant Camponotus floridanus, this hormone is present in the socially regurgitated fluid of workers. We investigated the role the social transfer of juvenile hormone in the social regulation of development. To do this, we administered an artificial regurgitate to larvae through a newly developed handfeeding method that was or was not supplemented with juvenile hormone. Orally administered juvenile hormone increased the nutritional needs of larvae, allowing them to reach a larger size at pupation. Instead of causing them to grow faster, the juvenile hormone treatment extended larval developmental time, allowing them to accumulate resources over a longer period. Handfeeding ant larvae with juvenile hormone resulted in larger adult workers after metamorphosis, suggesting a role for socially transferred juvenile hormone in the colony-level regulation of worker size over colony maturation.
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Affiliation(s)
- Matteo A. Negroni
- Department of Biology, University of Fribourg, Chemin du Musée 10, 1700, Fribourg, Switzerland
| | - Adria C. LeBoeuf
- Department of Biology, University of Fribourg, Chemin du Musée 10, 1700, Fribourg, Switzerland
- Department of Zoology, University of Cambridge, Downing Street, Cambridge, UK
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3
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Negroni MA, LeBoeuf AC. Metabolic division of labor in social insects. Curr Opin Insect Sci 2023; 59:101085. [PMID: 37454732 DOI: 10.1016/j.cois.2023.101085] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 07/05/2023] [Accepted: 07/11/2023] [Indexed: 07/18/2023]
Abstract
Social insects are known for reproductive and behavioral division of labor, but little attention has been paid to metabolic forms of division of labor. Metabolic division of labor is the partitioning of complementary metabolic tasks between individuals, and it is widespread in social insects. We define two forms of metabolic division of labor, homosynergetic and heterosynergetic, we pinpoint trophallaxis, trophic eggs, and cannibalism as the primary transfers underlying the homosynergetic form and discuss their evolution. We argue that homosynergetic metabolic division of labor underpins fundamental aspects of colony physiology and may be a necessary feature of superorganismal systems, impacting many life history traits. Investigating metabolic division of labor is necessary to understand major evolutionary transition(s) to superorganismality in social insects.
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Affiliation(s)
- Matteo A Negroni
- Department of Biology, University of Fribourg, Chemin du Musée 10, 1700 Fribourg, Switzerland.
| | - Adria C LeBoeuf
- Department of Biology, University of Fribourg, Chemin du Musée 10, 1700 Fribourg, Switzerland.
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4
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Fujioka H, Marchand M, LeBoeuf AC. Diacamma ants adjust liquid foraging strategies in response to biophysical constraints. Proc Biol Sci 2023; 290:20230549. [PMID: 37312541 DOI: 10.1098/rspb.2023.0549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023] Open
Abstract
Ant foragers provide food to the rest of the colony, often requiring transport over long distances. Foraging for liquid is challenging because it is difficult to transport and share. Many social insects store liquids inside the crop to transport them to the nest, and then regurgitate to distribute to nest-mates through a behaviour called trophallaxis. Some ants instead transport fluids with a riskier behaviour called pseudotrophallaxis-holding a drop of liquid between the mandibles through surface tension. Ants share this droplet with nest-mates without ingestion or regurgitation. We hypothesised that ants optimize their liquid-collection approach depending on viscosity. Using an ant that employs both trophallaxis and pseudotrophallaxis, we investigated the conditions where each liquid-collection behaviour is favoured by measuring biophysical properties, collection time and reaction to food quality for typical and viscosity-altered sucrose solutions. We found that ants collected more liquid per unit time by mandibular grabbing than by drinking. At high viscosities ants switched liquid collection method to mandibular grabbing in response to viscosity and not to sweetness. Our results demonstrate that ants change transport and sharing methods according to viscosity-a natural proxy for sugar concentration-thus increasing the mass of sugar returned to the nest per trip.
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Affiliation(s)
- Haruna Fujioka
- Faculty of Environmental and Life Science, Okayama University, Okayama, Japan
- Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Manon Marchand
- Department of Physics, University of Fribourg, Fribourg, Switzerland
| | - Adria C LeBoeuf
- Department of Biology, University of Fribourg, Fribourg, Switzerland
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5
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Hakala SM, Fujioka H, Gapp K, De Gasperin O, Genzoni E, Kilner RM, Koene JM, König B, Linksvayer TA, Meurville MP, Negroni MA, Palejowski H, Wigby S, LeBoeuf AC. Socially transferred materials: why and how to study them. Trends Ecol Evol 2022; 38:446-458. [PMID: 36543692 DOI: 10.1016/j.tree.2022.11.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Revised: 11/21/2022] [Accepted: 11/25/2022] [Indexed: 12/23/2022]
Abstract
When biological material is transferred from one individual's body to another, as in ejaculate, eggs, and milk, secondary donor-produced molecules are often transferred along with the main cargo, and influence the physiology and fitness of the receiver. Both social and solitary animals exhibit such social transfers at certain life stages. The secondary, bioactive, and transfer-supporting components in socially transferred materials have evolved convergently to the point where they are used in applications across taxa and type of transfer. The composition of these materials is typically highly dynamic and context dependent, and their components drive the physiological and behavioral evolution of many taxa. Our establishment of the concept of socially transferred materials unifies this multidisciplinary topic and will benefit both theory and applications.
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Hakala SM, Meurville MP, Stumpe M, LeBoeuf AC. Biomarkers in a socially exchanged /fluid reflect colony maturity, behavior, and distributed metabolism. eLife 2021; 10:74005. [PMID: 34725037 PMCID: PMC8608388 DOI: 10.7554/elife.74005] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Accepted: 10/15/2021] [Indexed: 12/24/2022] Open
Abstract
In cooperative systems exhibiting division of labor, such as microbial communities, multicellular organisms, and social insect colonies, individual units share costs and benefits through both task specialization and exchanged materials. Socially exchanged fluids, like seminal fluid and milk, allow individuals to molecularly influence conspecifics. Many social insects have a social circulatory system, where food and endogenously produced molecules are transferred mouth-to-mouth (stomodeal trophallaxis), connecting all the individuals in the society. To understand how these endogenous molecules relate to colony life, we used quantitative proteomics to investigate the trophallactic fluid within colonies of the carpenter ant Camponotus floridanus. We show that different stages of the colony life cycle circulate different types of proteins: young colonies prioritize direct carbohydrate processing; mature colonies prioritize accumulation and transmission of stored resources. Further, colonies circulate proteins implicated in oxidative stress, ageing, and social insect caste determination, potentially acting as superorganismal hormones. Brood-caring individuals that are also closer to the queen in the social network (nurses) showed higher abundance of oxidative stress-related proteins. Thus, trophallaxis behavior could provide a mechanism for distributed metabolism in social insect societies. The ability to thoroughly analyze the materials exchanged between cooperative units makes social insect colonies useful models to understand the evolution and consequences of metabolic division of labor at other scales. Division of labor is essential for cooperation, because groups can achieve more when individuals specialize in different tasks. This happens across the natural world, from different cells in organisms performing specific roles, to the individuals in an ant colony carrying out diverse duties. In both of these systems, individuals work together to ensure the survival of the collective unit – the body or the colony – instead of competing against each other. One of the main ways division of labor is evident within these two systems is regarding reproduction. Both in the body and in an ant colony, only one or a few individual units can reproduce, while the rest provide support. In the case of ant colonies, only queens and males reproduce, while the young workers nurse the brood and older workers forage for food. This intense cooperation requires close communication between individual units – in the case of some species of ants, by sharing fluids mouth-to-mouth. These fluids contain food but also many molecules produced by the ants themselves, including proteins. Given that both individuals and the colony as a whole change as they age – with workers acquiring new roles, and new queens and males only reared once the colony is mature – it is likely that the proteins transmitted in the fluid also change. To better understand whether the lifecycles of individuals and the age of the colony affect the fluids shared by carpenter ants Camponotus floridanus, Hakala et al. examined the ant-produced proteins in these fluids. This revealed differences in the proteins shared by young and mature colonies, and young nurse ants and older forager ants. In young colonies, the fluids contained proteins involved in fast sugar processing; while in mature colonies, the fluids contained more proteins to store nutrients, which help insect larvae grow into larger individuals, like queens. Young worker ants, who spend their time nursing the brood, produced more anti-aging proteins. This may be because these ants are in close contact with the queen, who lives much longer than the rest of the ants in the colony. Taken together, these observations suggest that ants divide the labor of metabolism, as well as work and reproduction. Dividing the labor of metabolism among individuals is one more similarity between ants and the cells of a multicellular organism, like a fly or a human. Division of labor allows the sharing of burden, with some individuals lightening the load of others. Understanding how ants achieve this by sharing fluids could shed new light on this complex exchange at other scales or in other organisms. By matching proteins to life stages, researchers have a starting point to examine individual molecules in more detail.
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Affiliation(s)
- Sanja M Hakala
- Department of Biology, University of Fribourg, Fribourg, Switzerland
| | | | - Michael Stumpe
- Metabolomics and Proteomics Platform, Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Adria C LeBoeuf
- Department of Biology, University of Fribourg, Fribourg, Switzerland
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7
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LeBoeuf AC, Waridel P, Brent CS, Gonçalves AN, Menin L, Ortiz D, Riba-Grognuz O, Koto A, Soares ZG, Privman E, Miska EA, Benton R, Keller L. Oral transfer of chemical cues, growth proteins and hormones in social insects. eLife 2019; 8:51082. [PMID: 31424387 PMCID: PMC6699857 DOI: 10.7554/elife.51082] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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8
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LeBoeuf AC, Waridel P, Brent CS, Gonçalves AN, Menin L, Ortiz D, Riba-Grognuz O, Koto A, Soares ZG, Privman E, Miska EA, Benton R, Keller L. Oral transfer of chemical cues, growth proteins and hormones in social insects. eLife 2016; 5:e20375. [PMID: 27894417 PMCID: PMC5153251 DOI: 10.7554/elife.20375] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Accepted: 11/14/2016] [Indexed: 01/02/2023] Open
Abstract
Social insects frequently engage in oral fluid exchange - trophallaxis - between adults, and between adults and larvae. Although trophallaxis is widely considered a food-sharing mechanism, we hypothesized that endogenous components of this fluid might underlie a novel means of chemical communication between colony members. Through protein and small-molecule mass spectrometry and RNA sequencing, we found that trophallactic fluid in the ant Camponotus floridanus contains a set of specific digestion- and non-digestion related proteins, as well as hydrocarbons, microRNAs, and a key developmental regulator, juvenile hormone. When C. floridanus workers' food was supplemented with this hormone, the larvae they reared via trophallaxis were twice as likely to complete metamorphosis and became larger workers. Comparison of trophallactic fluid proteins across social insect species revealed that many are regulators of growth, development and behavioral maturation. These results suggest that trophallaxis plays previously unsuspected roles in communication and enables communal control of colony phenotypes.
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Affiliation(s)
- Adria C LeBoeuf
- Center for Integrative GenomicsUniversity of LausanneLausanneSwitzerland
- Department of Ecology and EvolutionUniversity of LausanneLausanneSwitzerland
| | - Patrice Waridel
- Protein Analysis FacilityUniversity of LausanneLausanneSwitzerland
| | - Colin S Brent
- Arid Land Agricultural Research Center, USDA-ARSMaricopaUnited States
| | - Andre N Gonçalves
- Department of Biochemistry and ImmunologyInstituto de Ciências Biológicas, Universidade Federal de Minas GeraisMinas GeraisBrazil
- Gurdon InstituteUniversity of CambridgeCambridgeUnited Kingdom
| | - Laure Menin
- Institute of Chemical Sciences and EngineeringEcole Polytechnique Fédérale de LausanneLausanneSwitzerland
| | - Daniel Ortiz
- Institute of Chemical Sciences and EngineeringEcole Polytechnique Fédérale de LausanneLausanneSwitzerland
| | - Oksana Riba-Grognuz
- Department of Ecology and EvolutionUniversity of LausanneLausanneSwitzerland
| | - Akiko Koto
- The Department of Genetics, Graduate School of Pharmaceutical SciencesThe University of TokyoTokyoJapan
| | - Zamira G Soares
- Department of Biochemistry and ImmunologyInstituto de Ciências Biológicas, Universidade Federal de Minas GeraisMinas GeraisBrazil
- Gurdon InstituteUniversity of CambridgeCambridgeUnited Kingdom
| | - Eyal Privman
- Department of Evolutionary and Environmental Biology, Institute of EvolutionUniversity of HaifaHaifaIsrael
| | - Eric A Miska
- Gurdon InstituteUniversity of CambridgeCambridgeUnited Kingdom
- Department of GeneticsUniversity of CambridgeCambridgeUnited Kingdom
- Wellcome Trust Sanger InstituteWellcome Trust Genome CampusCambridgeUnited Kingdom
| | - Richard Benton
- Center for Integrative GenomicsUniversity of LausanneLausanneSwitzerland
| | - Laurent Keller
- Department of Ecology and EvolutionUniversity of LausanneLausanneSwitzerland
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9
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LeBoeuf AC, Grozinger CM. Me and we: the interplay between individual and group behavioral variation in social collectives. Curr Opin Insect Sci 2014; 5:16-24. [PMID: 32846737 DOI: 10.1016/j.cois.2014.09.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Revised: 09/12/2014] [Accepted: 09/17/2014] [Indexed: 06/11/2023]
Abstract
In social insects, substantial behavioral variation exists among individuals and across colonies. Here, we discuss the role of individual variation in shaping behavioral tendencies of social groups, and highlight gaps in our knowledge about the role of the social group in modulating individual behavioral tendencies. We summarize our knowledge of the genetic mechanisms underpinning these processes, and describe the use of genomic tools to better understand the influence of social context on individuals. We discuss rapid collective phasic transitions, in which a group of individuals engages in a common novel behavior together, as a potentially highly informative model system in which to comprehensively investigate the interplay between individual and group variation.
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Affiliation(s)
- Adria C LeBoeuf
- Department of Ecology and Evolution, Center for Integrative Genomics, University of Lausanne, UNIL-Sorge, Batiment Biophore, CH-1015 Lausanne, Switzerland
| | - Christina M Grozinger
- Department of Entomology, Center for Pollinator Research, Center for Chemical Ecology, The Pennsylvania State University, 1 Chemical Ecology Lab, Orchard Road, University Park, PA 16802, USA.
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10
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LeBoeuf AC, Benton R, Keller L. The molecular basis of social behavior: models, methods and advances. Curr Opin Neurobiol 2013; 23:3-10. [DOI: 10.1016/j.conb.2012.08.008] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2012] [Revised: 08/24/2012] [Accepted: 08/29/2012] [Indexed: 12/30/2022]
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11
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LeBoeuf AC, Ó Maoiléidigh D, Hudspeth AJ. Divalent counterions tether membrane-bound carbohydrates to promote the cohesion of auditory hair bundles. Biophys J 2011; 101:1316-25. [PMID: 21943412 DOI: 10.1016/j.bpj.2011.07.053] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2011] [Revised: 07/13/2011] [Accepted: 07/28/2011] [Indexed: 11/16/2022] Open
Abstract
The cell membranes in the hair bundle of an auditory hair cell confront a difficult task as the bundle oscillates in response to sound: for efficient mechanotransduction, all the component stereocilia of the hair bundle must move essentially in unison, shearing at their tips yet maintaining contact without membrane fusion. One mechanism by which this cohesion might occur is counterion-mediated attachment between glycan components of apposed stereociliary membranes. Using capillary electrophoresis, we showed that the stereociliary glycocalyx acts as a negatively charged polymer brush. We found by force-sensing photomicrometry that the stereocilia formed elastic connections with one another to various degrees depending on the surrounding ionic environment and the presence of N-linked sugars. Mg(2+) was a more potent mediator of attachment than was Ca(2+). The forces between stereocilia produced chaotic stick-slip behavior. These results indicate that counterion-mediated interactions in the glycocalyx contribute to the stereociliary coherence that is essential for hearing.
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Affiliation(s)
- Adria C LeBoeuf
- Howard Hughes Medical Institute and Laboratory of Sensory Neuroscience, The Rockefeller University, New York, New York, USA
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12
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LeBoeuf AC, Levy SF, Gaylord M, Bhattacharya A, Singh AK, Jordan MA, Wilson L, Feinstein SC. FTDP-17 mutations in Tau alter the regulation of microtubule dynamics: an "alternative core" model for normal and pathological Tau action. J Biol Chem 2008; 283:36406-15. [PMID: 18940799 DOI: 10.1074/jbc.m803519200] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Mutations affecting either the structure or regulation of the microtubule-associated protein Tau cause neuronal cell death and dementia. However, the molecular mechanisms mediating these deleterious effects remain unclear. Among the most characterized activities of Tau is the ability to regulate microtubule dynamics, known to be essential for proper cell function and viability. Here we have tested the hypothesis that Tau mutations causing neurodegeneration also alter the ability of Tau to regulate the dynamic instability behaviors of microtubules. Using in vitro microtubule dynamics assays to assess average microtubule growth rates, microtubule growth rate distributions, and catastrophe frequencies, we found that all tested mutants possessing amino acid substitutions or deletions mapping to either the repeat or interrepeat regions of Tau do indeed compromise its ability to regulate microtubule dynamics. Further mutational analyses suggest a novel mechanism of Tau regulatory action based on an "alternative core" of microtubule binding and regulatory activities composed of two repeats and the interrepeat between them. In this model, the interrepeat serves as the primary regulator of microtubule dynamics, whereas the flanking repeats serve as tethers to properly position the interrepeat on the microtubule. Importantly, since there are multiple interrepeats on each Tau molecule, there are also multiple cores on each Tau molecule, each with distinct mechanistic capabilities, thereby providing significant regulatory potential. Taken together, the data are consistent with a microtubule misregulation mechanism for Tau-mediated neuronal cell death and provide a novel mechanistic model for normal and pathological Tau action.
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Affiliation(s)
- Adria C LeBoeuf
- Neuroscience Research Institute and Department of Molecular and Cellular and Developmental Biology, University of California, Santa Barbara, CA 93106, USA
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