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Banavar SP, Nelson CM. Mechanical properties pattern the skin. Science 2023; 382:880. [PMID: 37995222 DOI: 10.1126/science.adl2004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2023]
Abstract
Morphogens induce variations in tissue mechanics to promote feather budding.
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Affiliation(s)
- Samhita P Banavar
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ, USA
| | - Celeste M Nelson
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ, USA
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA
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2
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Parada C, Banavar SP, Khalilian P, Rigaud S, Michaut A, Liu Y, Joshy DM, Campàs O, Gros J. Mechanical feedback defines organizing centers to drive digit emergence. Dev Cell 2022; 57:854-866.e6. [PMID: 35413235 DOI: 10.1016/j.devcel.2022.03.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 01/25/2022] [Accepted: 03/10/2022] [Indexed: 11/03/2022]
Abstract
During embryonic development, digits gradually emerge in a periodic pattern. Although genetic evidence indicates that digit formation results from a self-organizing process, the underlying mechanisms are still unclear. Here, we find that convergent-extension tissue flows driven by active stresses underlie digit formation. These active stresses simultaneously shape cartilage condensations and lead to the emergence of a compressive stress region that promotes high activin/p-SMAD/SOX9 expression, thereby defining digit-organizing centers via a mechanical feedback. In Wnt5a mutants, such mechanical feedback is disrupted due to the loss of active stresses, organizing centers do not emerge, and digit formation is precluded. Thus, digit emergence does not result solely from molecular interactions, as was previously thought, but requires a mechanical feedback that ensures continuous coupling between phalanx specification and elongation. Our work, which links mechanical and molecular signals, provides a mechanistic context for the emergence of organizing centers that may underlie various developmental processes.
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Affiliation(s)
- Carolina Parada
- Department of Developmental and Stem Cell Biology, Institut Pasteur, 75724 Paris Cedex 15, France; CNRS UMR 3738, 25 rue du Dr Roux, 75015 Paris, France
| | - Samhita P Banavar
- Department of Physics, University of California, Santa Barbara, CA 93106-5070, USA
| | - Parisa Khalilian
- Department of Developmental and Stem Cell Biology, Institut Pasteur, 75724 Paris Cedex 15, France; CNRS UMR 3738, 25 rue du Dr Roux, 75015 Paris, France
| | - Stephane Rigaud
- Image Analysis Hub, C2RT, Institut Pasteur, 75724 Paris Cedex 15, France
| | - Arthur Michaut
- Department of Developmental and Stem Cell Biology, Institut Pasteur, 75724 Paris Cedex 15, France; CNRS UMR 3738, 25 rue du Dr Roux, 75015 Paris, France
| | - Yucen Liu
- Department of Mechanical Engineering, University of California, Santa Barbara, CA 93106-5070, USA
| | - Dennis Manjaly Joshy
- Department of Mechanical Engineering, University of California, Santa Barbara, CA 93106-5070, USA
| | - Otger Campàs
- Department of Mechanical Engineering, University of California, Santa Barbara, CA 93106-5070, USA; Department of Molecular, Cell and Developmental Biology, University of California, Santa Barbara, CA, USA; Cluster of Excellence Physics of Life, TU Dresden, 01062 Dresden, Germany.
| | - Jerome Gros
- Department of Developmental and Stem Cell Biology, Institut Pasteur, 75724 Paris Cedex 15, France; CNRS UMR 3738, 25 rue du Dr Roux, 75015 Paris, France.
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3
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Doshi S, Banavar SP, Flaum E, Kulkarni S, Vaidya U, Kumar S, Chen T, Bhattacharya A, Prakash M. Applying heat and humidity using stove boiled water for decontamination of N95 respirators in low resource settings. PLoS One 2021; 16:e0255338. [PMID: 34591858 PMCID: PMC8483377 DOI: 10.1371/journal.pone.0255338] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 07/14/2021] [Indexed: 11/27/2022] Open
Abstract
Global shortages of N95 respirators have led to an urgent need of N95 decontamination and reuse methods that are scientifically validated and available world-wide. Although several large scale decontamination methods have been proposed (hydrogen peroxide vapor, UV-C); many of them are not applicable in remote and low-resource settings. Heat with humidity has been demonstrated as a promising decontamination approach, but care must be taken when implementing this method at a grassroots level. Here we present a simple, scalable method to provide controlled humidity and temperature for individual N95 respirators which is easily applicable in low-resource settings. N95 respirators were subjected to moist heat (>50% relative humidity, 65-80°C temperature) for over 30 minutes by placing them in a sealed container immersed in water that had been brought to a rolling boil and removed from heat, and then allowing the containers to sit for over 45 minutes. Filtration efficiency of 0.3-4.99 μm incense particles remained above 97% after 5 treatment cycles across all particle size sub-ranges. This method was then repeated at a higher ambient temperature and humidity in Mumbai, using standard utensils commonly found in South Asia. Similar temperature and humidity profiles were achieved with no degradation in filtration efficiencies after 6 cycles. Higher temperatures (>70°C) and longer treatment times (>40 minutes) were obtained by insulating the outer vessel. We also showed that the same method can be applied for the decontamination of surgical masks. This simple yet reliable method can be performed even without electricity access using any heat source to boil water, from open-flame stoves to solar heating, and provides a low-cost route for N95 decontamination globally applicable in resource-constrained settings.
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Affiliation(s)
- Siddharth Doshi
- Department of Materials Science and Engineering, Stanford University, Stanford, California, United States of America
| | - Samhita P. Banavar
- Department of Bioengineering, Stanford University, Stanford, California, United States of America
| | - Eliott Flaum
- Department of Bioengineering, Stanford University, Stanford, California, United States of America
- Graduate Program in Biophysics, Stanford University, Stanford, California, United States of America
| | | | - Ulhas Vaidya
- Tata Institute of Fundamental Research, Mumbai, India
| | - Shailabh Kumar
- Department of Bioengineering, Stanford University, Stanford, California, United States of America
| | - Tyler Chen
- Department of Bioengineering, Stanford University, Stanford, California, United States of America
| | | | - Manu Prakash
- Department of Bioengineering, Stanford University, Stanford, California, United States of America
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Banavar SP, Carn EK, Rowghanian P, Stooke-Vaughan G, Kim S, Campàs O. Mechanical control of tissue shape and morphogenetic flows during vertebrate body axis elongation. Sci Rep 2021; 11:8591. [PMID: 33883563 PMCID: PMC8060277 DOI: 10.1038/s41598-021-87672-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 03/30/2021] [Indexed: 02/02/2023] Open
Abstract
Shaping embryonic tissues into their functional morphologies requires cells to control the physical state of the tissue in space and time. While regional variations in cellular forces or cell proliferation have been typically assumed to be the main physical factors controlling tissue morphogenesis, recent experiments have revealed that spatial variations in the tissue physical (fluid/solid) state play a key role in shaping embryonic tissues. Here we theoretically study how the regional control of fluid and solid tissue states guides morphogenetic flows to shape the extending vertebrate body axis. Our results show that both the existence of a fluid-to-solid tissue transition along the anteroposterior axis and the tissue surface tension determine the shape of the tissue and its ability to elongate unidirectionally, with large tissue tensions preventing unidirectional elongation and promoting blob-like tissue expansions. We predict both the tissue morphogenetic flows and stresses that enable unidirectional axis elongation. Our results show the existence of a sharp transition in the structure of morphogenetic flows, from a flow with no vortices to a flow with two counter-rotating vortices, caused by a transition in the number and location of topological defects in the flow field. Finally, comparing the theoretical predictions to quantitative measurements of both tissue flows and shape during zebrafish body axis elongation, we show that the observed morphogenetic events can be explained by the existence of a fluid-to-solid tissue transition along the anteroposterior axis. These results highlight the role of spatiotemporally-controlled fluid-to-solid transitions in the tissue state as a physical mechanism of embryonic morphogenesis.
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Affiliation(s)
- Samhita P Banavar
- Department of Physics, University of California, Santa Barbara, CA, 93106, USA
- California NanoSystems Institute, University of California, Santa Barbara, CA, 93106, USA
- Stanford University, Stanford, CA, USA
| | - Emmet K Carn
- Department of Mechanical Engineering, University of California, Santa Barbara, CA, 93106, USA
- California NanoSystems Institute, University of California, Santa Barbara, CA, 93106, USA
| | - Payam Rowghanian
- Department of Mechanical Engineering, University of California, Santa Barbara, CA, 93106, USA
- California NanoSystems Institute, University of California, Santa Barbara, CA, 93106, USA
| | - Georgina Stooke-Vaughan
- Department of Mechanical Engineering, University of California, Santa Barbara, CA, 93106, USA
- California NanoSystems Institute, University of California, Santa Barbara, CA, 93106, USA
| | - Sangwoo Kim
- Department of Mechanical Engineering, University of California, Santa Barbara, CA, 93106, USA
- California NanoSystems Institute, University of California, Santa Barbara, CA, 93106, USA
| | - Otger Campàs
- Department of Mechanical Engineering, University of California, Santa Barbara, CA, 93106, USA.
- California NanoSystems Institute, University of California, Santa Barbara, CA, 93106, USA.
- Department of Molecular, Cell and Developmental Biology, University of California, Santa Barbara, CA, 93106, USA.
- Center for Bioengineering, University of California, Santa Barbara, CA, 93106, USA.
- Cluster of Excellence Physics of Life, TU Dresden, 01062, Dresden, Germany.
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5
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Kroo L, Kothari A, Hannebelle M, Herring G, Pollina T, Chang R, Peralta D, Banavar SP, Flaum E, Soto-Montoya H, Li H, Combes K, Pan E, Vu K, Yen K, Dale J, Kolbay P, Ellgas S, Konte R, Hajian R, Zhong G, Jacobs N, Jain A, Kober F, Ayala G, Allinne Q, Cucinelli N, Kasper D, Borroni L, Gerber P, Venook R, Baek P, Arora N, Wagner P, Miki R, Kohn J, Kohn Bitran D, Pearson J, Arias-Arco B, Larrainzar-Garijo R, Herrera CM, Prakash M. Modified full-face snorkel masks as reusable personal protective equipment for hospital personnel. PLoS One 2021; 16:e0244422. [PMID: 33439902 PMCID: PMC7806161 DOI: 10.1371/journal.pone.0244422] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Accepted: 12/09/2020] [Indexed: 11/19/2022] Open
Abstract
Here we adapt and evaluate a full-face snorkel mask for use as personal protective equipment (PPE) for health care workers, who lack appropriate alternatives during the COVID-19 crisis in the spring of 2020. The design (referred to as Pneumask) consists of a custom snorkel-specific adapter that couples the snorkel-port of the mask to a rated filter (either a medical-grade ventilator inline filter or an industrial filter). This design has been tested for the sealing capability of the mask, filter performance, CO2 buildup and clinical usability. These tests found the Pneumask capable of forming a seal that exceeds the standards required for half-face respirators or N95 respirators. Filter testing indicates a range of options with varying performance depending on the quality of filter selected, but with typical filter performance exceeding or comparable to the N95 standard. CO2 buildup was found to be roughly equivalent to levels found in half-face elastomeric respirators in literature. Clinical usability tests indicate sufficient visibility and, while speaking is somewhat muffled, this can be addressed via amplification (Bluetooth voice relay to cell phone speakers through an app) in noisy environments. We present guidance on the assembly, usage (donning and doffing) and decontamination protocols. The benefit of the Pneumask as PPE is that it is reusable for longer periods than typical disposable N95 respirators, as the snorkel mask can withstand rigorous decontamination protocols (that are standard to regular elastomeric respirators). With the dire worldwide shortage of PPE for medical personnel, our conclusions on the performance and efficacy of Pneumask as an N95-alternative technology are cautiously optimistic.
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Affiliation(s)
- Laurel Kroo
- Department of Mechanical Engineering, Stanford University, Stanford, CA, United States of America
| | - Anesta Kothari
- Department of Bioengineering, Stanford University, Stanford, CA, United States of America
| | - Melanie Hannebelle
- Swiss Federal Institute of Technology (EPFL), School of Engineering, Lausanne, Switzerland
- Swiss Federal Institute of Technology (EPFL), School of Life Sciences, Lausanne, Switzerland
| | - George Herring
- Department of Bioengineering, Stanford University, Stanford, CA, United States of America
- Department of Electrical Engineering, Stanford University, Stanford, CA, United States of America
| | - Thibaut Pollina
- Department of Bioengineering, Stanford University, Stanford, CA, United States of America
| | - Ray Chang
- Department of Bioengineering, Stanford University, Stanford, CA, United States of America
| | | | - Samhita P. Banavar
- Department of Bioengineering, Stanford University, Stanford, CA, United States of America
| | - Eliott Flaum
- Stanford University, Biophysics Program, Stanford, CA, United States of America
| | - Hazel Soto-Montoya
- Department of Bioengineering, Stanford University, Stanford, CA, United States of America
| | - Hongquan Li
- Department of Electrical Engineering, Stanford University, Stanford, CA, United States of America
| | - Kyle Combes
- Olin College of Engineering, Needham, MA, United States of America
| | - Emma Pan
- Olin College of Engineering, Needham, MA, United States of America
| | - Khang Vu
- Olin College of Engineering, Needham, MA, United States of America
| | - Kelly Yen
- Olin College of Engineering, Needham, MA, United States of America
| | | | - Patrick Kolbay
- Department of Bioengineering, University of Utah, Salt Lake City, UT, United States of America
- Department of Anesthesiology, University of Utah, Salt Lake City, UT, United States of America
| | - Simon Ellgas
- Waymo, Mountain View, CA, United States of America
| | - Rebecca Konte
- Department of Bioengineering, Stanford University, Stanford, CA, United States of America
| | - Rozhin Hajian
- Department of Applied Mathematics, Harvard University, Cambridge, MA, United States of America
| | - Grace Zhong
- Department of Bioengineering, Stanford University, Stanford, CA, United States of America
| | | | - Amit Jain
- Mountain View, CA, United States of America
| | | | - Gerry Ayala
- Wildhorn Outfitters, Draper, Salt Lake City, UT, United States of America
| | | | - Nicholas Cucinelli
- University of Michigan, Entrepreneurial Leadership Faculty, Ann Arbor, MI, United States of America
| | - Dave Kasper
- iSnorkel Inc, Dexter, Salt Lake City, UT, United States of America
| | | | - Patrick Gerber
- Swiss Federal Institute of Technology (EPFL), Safety, Prevention and Health Domain, Lausanne, Switzerland
| | - Ross Venook
- Department of Bioengineering, Stanford University, Stanford, CA, United States of America
| | - Peter Baek
- U.S. Anesthesia Partners Texas, Dallas, TX, United States of America
| | - Nitin Arora
- University of Alabama at Birmingham, Birmingham, AL, United States of America
| | - Philip Wagner
- Hospital for Special Surgery, New York City, NY, United States of America
| | - Roberto Miki
- Miki & Alfonso Hand & Upper Extremity Center, Miami, FL, United States of America
| | - Jocelyne Kohn
- Instituto de Oftalmologia, Ophthalmologist, Santiago, Chile
| | | | - John Pearson
- Department of Anesthesiology, University of Utah, Salt Lake City, UT, United States of America
| | | | | | | | - Manu Prakash
- Department of Bioengineering, Stanford University, Stanford, CA, United States of America
- * E-mail:
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Banavar SP, Trogdon M, Drawert B, Yi TM, Petzold LR, Campàs O. Coordinating cell polarization and morphogenesis through mechanical feedback. PLoS Comput Biol 2021; 17:e1007971. [PMID: 33507956 PMCID: PMC7872284 DOI: 10.1371/journal.pcbi.1007971] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 02/09/2021] [Accepted: 12/21/2020] [Indexed: 12/30/2022] Open
Abstract
Many cellular processes require cell polarization to be maintained as the cell changes shape, grows or moves. Without feedback mechanisms relaying information about cell shape to the polarity molecular machinery, the coordination between cell polarization and morphogenesis, movement or growth would not be possible. Here we theoretically and computationally study the role of a genetically-encoded mechanical feedback (in the Cell Wall Integrity pathway) as a potential coordination mechanism between cell morphogenesis and polarity during budding yeast mating projection growth. We developed a coarse-grained continuum description of the coupled dynamics of cell polarization and morphogenesis as well as 3D stochastic simulations of the molecular polarization machinery in the evolving cell shape. Both theoretical approaches show that in the absence of mechanical feedback (or in the presence of weak feedback), cell polarity cannot be maintained at the projection tip during growth, with the polarization cap wandering off the projection tip, arresting morphogenesis. In contrast, for mechanical feedback strengths above a threshold, cells can robustly maintain cell polarization at the tip and simultaneously sustain mating projection growth. These results indicate that the mechanical feedback encoded in the Cell Wall Integrity pathway can provide important positional information to the molecular machinery in the cell, thereby enabling the coordination of cell polarization and morphogenesis.
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Affiliation(s)
- Samhita P. Banavar
- Department of Physics, University of California, University of California, Santa Barbara, California, United States of America
- California NanoSystems Institute, University of California, Santa Barbara, California, United States of America
| | - Michael Trogdon
- Department of Mechanical Engineering, University of California, Santa Barbara, California, United States of America
| | - Brian Drawert
- Department of Computer Science, University of North Carolina, Asheville, North Carolina, United States of America
| | - Tau-Mu Yi
- Department of Molecular, Cell and Developmental Biology, University of California, Santa Barbara, California, United States of America
| | - Linda R. Petzold
- Department of Mechanical Engineering, University of California, Santa Barbara, California, United States of America
- Center for Bioengineering, University of California, Santa Barbara, California, United States of America
| | - Otger Campàs
- California NanoSystems Institute, University of California, Santa Barbara, California, United States of America
- Department of Mechanical Engineering, University of California, Santa Barbara, California, United States of America
- Department of Molecular, Cell and Developmental Biology, University of California, Santa Barbara, California, United States of America
- Center for Bioengineering, University of California, Santa Barbara, California, United States of America
- Cluster of Excellence Physics of Life, TU Dresden, Dresden, Germany
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Trogdon M, Drawert B, Gomez C, Banavar SP, Yi TM, Campàs O, Petzold LR. The effect of cell geometry on polarization in budding yeast. PLoS Comput Biol 2018; 14:e1006241. [PMID: 29889845 PMCID: PMC6013239 DOI: 10.1371/journal.pcbi.1006241] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 06/21/2018] [Accepted: 05/29/2018] [Indexed: 11/19/2022] Open
Abstract
The localization (or polarization) of proteins on the membrane during the mating of budding yeast (Saccharomyces cerevisiae) is an important model system for understanding simple pattern formation within cells. While there are many existing mathematical models of polarization, for both budding and mating, there are still many aspects of this process that are not well understood. In this paper we set out to elucidate the effect that the geometry of the cell can have on the dynamics of certain models of polarization. Specifically, we look at several spatial stochastic models of Cdc42 polarization that have been adapted from published models, on a variety of tip-shaped geometries, to replicate the shape change that occurs during the growth of the mating projection. We show here that there is a complex interplay between the dynamics of polarization and the shape of the cell. Our results show that while models of polarization can generate a stable polarization cap, its localization at the tip of mating projections is unstable, with the polarization cap drifting away from the tip of the projection in a geometry dependent manner. We also compare predictions from our computational results to experiments that observe cells with projections of varying lengths, and track the stability of the polarization cap. Lastly, we examine one model of actin polarization and show that it is unlikely, at least for the models studied here, that actin dynamics and vesicle traffic are able to overcome this effect of geometry.
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Affiliation(s)
- Michael Trogdon
- Department of Mechanical Engineering, University of California, Santa Barbara, Santa Barbara, California, United States of America
- * E-mail:
| | - Brian Drawert
- Department of Computer Science, University of North Carolina, Asheville, Asheville, North Carolina, United States of America
| | - Carlos Gomez
- Department of Molecular, Cell and Developmental Biology, University of California, Santa Barbara, Santa Barbara, California, United States of America
- California NanoSystems Institute, University of California, Santa Barbara, Santa Barbara, California, United States of America
| | - Samhita P. Banavar
- California NanoSystems Institute, University of California, Santa Barbara, Santa Barbara, California, United States of America
- Department of Physics, University of California, Santa Barbara, Santa Barbara, California, United States of America
| | - Tau-Mu Yi
- Department of Molecular, Cell and Developmental Biology, University of California, Santa Barbara, Santa Barbara, California, United States of America
| | - Otger Campàs
- Department of Mechanical Engineering, University of California, Santa Barbara, Santa Barbara, California, United States of America
- Department of Molecular, Cell and Developmental Biology, University of California, Santa Barbara, Santa Barbara, California, United States of America
- California NanoSystems Institute, University of California, Santa Barbara, Santa Barbara, California, United States of America
- Center for Bioengineering, University of California, Santa Barbara, Santa Barbara, California, United States of America
| | - Linda R. Petzold
- Department of Mechanical Engineering, University of California, Santa Barbara, Santa Barbara, California, United States of America
- Center for Bioengineering, University of California, Santa Barbara, Santa Barbara, California, United States of America
- Department of Computer Science, University of California, Santa Barbara, Santa Barbara, California, United States of America
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Banavar SP, Gomez C, Trogdon M, Petzold LR, Yi TM, Campàs O. Mechanical feedback coordinates cell wall expansion and assembly in yeast mating morphogenesis. PLoS Comput Biol 2018; 14:e1005940. [PMID: 29346368 PMCID: PMC5790295 DOI: 10.1371/journal.pcbi.1005940] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 01/30/2018] [Accepted: 12/22/2017] [Indexed: 11/18/2022] Open
Abstract
The shaping of individual cells requires a tight coordination of cell mechanics and growth. However, it is unclear how information about the mechanical state of the wall is relayed to the molecular processes building it, thereby enabling the coordination of cell wall expansion and assembly during morphogenesis. Combining theoretical and experimental approaches, we show that a mechanical feedback coordinating cell wall assembly and expansion is essential to sustain mating projection growth in budding yeast (Saccharomyces cerevisiae). Our theoretical results indicate that the mechanical feedback provided by the Cell Wall Integrity pathway, with cell wall stress sensors Wsc1 and Mid2 increasingly activating membrane-localized cell wall synthases Fks1/2 upon faster cell wall expansion, stabilizes mating projection growth without affecting cell shape. Experimental perturbation of the osmotic pressure and cell wall mechanics, as well as compromising the mechanical feedback through genetic deletion of the stress sensors, leads to cellular phenotypes that support the theoretical predictions. Our results indicate that while the existence of mechanical feedback is essential to stabilize mating projection growth, the shape and size of the cell are insensitive to the feedback.
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Affiliation(s)
- Samhita P. Banavar
- Department of Physics, University of California, Santa Barbara, Santa Barbara, California, United States of America
- California NanoSystems Institute, University of California, Santa Barbara, Santa Barbara, California, United States of America
| | - Carlos Gomez
- California NanoSystems Institute, University of California, Santa Barbara, Santa Barbara, California, United States of America
- Department of Molecular, Cell and Developmental Biology, University of California, Santa Barbara, Santa Barbara, California, United States of America
| | - Michael Trogdon
- Department of Mechanical Engineering, University of California, Santa Barbara, Santa Barbara, California, United States of America
| | - Linda R. Petzold
- Department of Mechanical Engineering, University of California, Santa Barbara, Santa Barbara, California, United States of America
- Center for Bioengineering, University of California, Santa Barbara, Santa Barbara, United States of America
| | - Tau-Mu Yi
- Department of Molecular, Cell and Developmental Biology, University of California, Santa Barbara, Santa Barbara, California, United States of America
| | - Otger Campàs
- California NanoSystems Institute, University of California, Santa Barbara, Santa Barbara, California, United States of America
- Department of Molecular, Cell and Developmental Biology, University of California, Santa Barbara, Santa Barbara, California, United States of America
- Department of Mechanical Engineering, University of California, Santa Barbara, Santa Barbara, California, United States of America
- Center for Bioengineering, University of California, Santa Barbara, Santa Barbara, United States of America
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