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Yao M, Tijore A, Cheng D, Li JV, Hariharan A, Martinac B, Tran Van Nhieu G, Cox CD, Sheetz M. Force- and cell state-dependent recruitment of Piezo1 drives focal adhesion dynamics and calcium entry. Sci Adv 2022; 8:eabo1461. [PMID: 36351022 PMCID: PMC9645726 DOI: 10.1126/sciadv.abo1461] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 09/21/2022] [Indexed: 11/11/2022]
Abstract
Mechanosensing is an integral part of many physiological processes including stem cell differentiation, fibrosis, and cancer progression. Two major mechanosensing systems-focal adhesions and mechanosensitive ion channels-can convert mechanical features of the microenvironment into biochemical signals. We report here unexpectedly that the mechanosensitive calcium-permeable channel Piezo1, previously perceived to be diffusive on plasma membranes, binds to matrix adhesions in a force-dependent manner, promoting cell spreading, adhesion dynamics, and calcium entry in normal but not in most cancer cells tested except some glioblastoma lines. A linker domain in Piezo1 is needed for binding to adhesions, and overexpression of the domain blocks Piezo1 binding to adhesions, decreasing adhesion size and cell spread area. Thus, we suggest that Piezo1 is a previously unidentified component of focal adhesions in nontransformed cells that catalyzes adhesion maturation and growth through force-dependent calcium signaling, but this function is absent in most cancer cells.
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Affiliation(s)
- Mingxi Yao
- Department of Biomedical Engineering, Southern University of Science and Technology, Shenzhen 518055, China
- Guangdong Provincial Key Laboratory of Advanced Biomaterials, Southern University of Science and Technology, Shenzhen 518055, China
- Mechanobiology Institute, National University of Singapore, Singapore 117411
- Corresponding author. (M.Y); (C.C.); (M.S.)
| | - Ajay Tijore
- Mechanobiology Institute, National University of Singapore, Singapore 117411
- Center for Biosystems Science and Engineering, Indian Institute of Science, Bangalore 560012, India
| | - Delfine Cheng
- Victor Chang Cardiac Research Institute, Sydney NSW 2010, Australia
| | - Jinyuan Vero Li
- Victor Chang Cardiac Research Institute, Sydney NSW 2010, Australia
| | - Anushya Hariharan
- Mechanobiology Institute, National University of Singapore, Singapore 117411
| | - Boris Martinac
- Victor Chang Cardiac Research Institute, Sydney NSW 2010, Australia
| | - Guy Tran Van Nhieu
- Ecole Normale Supérieure Paris-Saclay Gif-sur-Yvette, France
- Team Ca Signaling and Microbial Infections, Institute for Integrative Biology of the Cell–CNRS UMR9198–Inserm U1280, 1, Avenue de la Terrasse, 91190 Gif-sur-Yvette, France
| | - Charles D. Cox
- Victor Chang Cardiac Research Institute, Sydney NSW 2010, Australia
- Corresponding author. (M.Y); (C.C.); (M.S.)
| | - Michael Sheetz
- Mechanobiology Institute, National University of Singapore, Singapore 117411
- Department of Biological Sciences, National University of Singapore, Singapore 117558
- Molecular MechanoMedicine Program, Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA
- Corresponding author. (M.Y); (C.C.); (M.S.)
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Tijore A, Yang B, Sheetz M. Cancer cells can be killed mechanically or with combinations of cytoskeletal inhibitors. Front Pharmacol 2022; 13:955595. [PMID: 36299893 PMCID: PMC9589226 DOI: 10.3389/fphar.2022.955595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2022] [Accepted: 08/12/2022] [Indexed: 12/24/2022] Open
Abstract
For over two centuries, clinicians have hypothesized that cancer developed preferentially at the sites of repeated damage, indicating that cancer is basically “continued healing.” Tumor cells can develop over time into other more malignant types in different environments. Interestingly, indefinite growth correlates with the depletion of a modular, early rigidity sensor, whereas restoring these sensors in tumor cells blocks tumor growth on soft surfaces and metastases. Importantly, normal and tumor cells from many different tissues exhibit transformed growth without the early rigidity sensor. When sensors are restored in tumor cells by replenishing depleted mechanosensory proteins that are often cytoskeletal, cells revert to normal rigidity-dependent growth. Surprisingly, transformed growth cells are sensitive to mechanical stretching or ultrasound which will cause apoptosis of transformed growth cells (Mechanoptosis). Mechanoptosis is driven by calcium entry through mechanosensitive Piezo1 channels that activate a calcium-induced calpain response commonly found in tumor cells. Since tumor cells from many different tissues are in a transformed growth state that is, characterized by increased growth, an altered cytoskeleton and mechanoptosis, it is possible to inhibit growth of many different tumors by mechanical activity and potentially by cytoskeletal inhibitors.
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Affiliation(s)
- Ajay Tijore
- Centre for Biosystems Science and Engineering, Indian Institute of Science, Bangalore, India
- *Correspondence: Ajay Tijore, ; Michael Sheetz,
| | - Bo Yang
- Mechanobiology Institute, National University of Singapore, Singapore, Singapore
| | - Michael Sheetz
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, United States
- *Correspondence: Ajay Tijore, ; Michael Sheetz,
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McNamara CR, Panigrahy A, Sheetz M, Berger RP. The Likelihood of an Occult Fracture in Skeletal Surveys Obtained in Children More Than 2 Years Old With Concerns of Physical Abuse. Pediatr Emerg Care 2022; 38:e488-e492. [PMID: 34009892 DOI: 10.1097/pec.0000000000002440] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVES Skeletal surveys are necessary in the evaluation for physical abuse in children less than 2 years old, but when to obtain a skeletal survey in older children is less clear. METHODS A retrospective study of patients older than 2 years who underwent skeletal survey over a 3-year period after implementation of an electronic health record physical abuse order set was conducted. Data were analyzed using descriptive statistics and compared with data from a cohort before order set implementation. The radiation dose of a skeletal survey in a 5-year old was calculated using a previously published technique. RESULTS There were 325 skeletal surveys, a marked increase in the rate of skeletal surveys compared with before order set implementation. Less than 2% (6/325) of skeletal surveys demonstrated an occult fracture. Of the 6 patients with occult fractures, 4 were physically abused; in each case, the diagnosis of abuse was evident before the skeletal survey. The other 2 patients fell from windows. The radiation exposure was 0.34 mSv. CONCLUSIONS The rate of occult fractures on skeletal survey is significantly lower than previously reported. This is likely because our population included all children who underwent skeletal survey and not the subset referred to a child abuse pediatrician. In addition, our data demonstrate that in children older than 2 years, skeletal surveys are unlikely to assist in making a diagnosis of physical abuse. The radiation exposure in a 5-year-old is 70% greater than in an infant, but still a dose, which represents a negligible health risk.
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Affiliation(s)
| | - Ashok Panigrahy
- Department of Pediatric Radiology, UPMC Children's Hospital of Pittsburgh
| | | | - Rachel P Berger
- Department of Pediatrics, Division of Child Advocacy, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA
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Fu C, Arora A, Engl W, Sheetz M, Viasnoff V. Cooperative regulation of adherens junction expansion through Epidermal Growth Factor Receptor (EGFR) activation. J Cell Sci 2022; 135:274477. [DOI: 10.1242/jcs.258929] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 01/12/2022] [Indexed: 11/20/2022] Open
Abstract
The mechanisms controlling the dynamics of expansion of adherens junctions are significantly less understood than those controlling their static properties. Here, we report that for suspended cell aggregates, the time to form a new junction between two cells speeds up with the number of junctions that the cells are already engaged in. Upon junction formation, the activation of the Epidermal Growth Factor Receptor (EGFR) distally affects the actin turnover dynamics of the cell-free cortex. The “primed” actin cortex results in a faster expansion of the subsequent new junctions. In such aggregates, we show that this mechanism results in a cooperative acceleration of the junction expansion dynamics (kinetype) but leaves the cell contractility, and hence the final junction size (phenotype), unaltered.
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Affiliation(s)
- Chaoyu Fu
- Mechanobiology Institute, National University of Singapore, Singapore, Singapore
| | - Aditya Arora
- Mechanobiology Institute, National University of Singapore, Singapore, Singapore
| | - Wilfried Engl
- Mechanobiology Institute, National University of Singapore, Singapore, Singapore
| | - Michael Sheetz
- Mechanobiology Institute, National University of Singapore, Singapore, Singapore
- Biochemistry and Molecular Biology Department, University of Texas Medical Branch, Galveston, Texas, USA
| | - Virgile Viasnoff
- Mechanobiology Institute, National University of Singapore, Singapore, Singapore
- CNRS Biomechanics of Cell Contacts, Singapore, Singapore
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
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Singh A, Tijore A, Margadant F, Simpson C, Chitkara D, Low BC, Sheetz M. Enhanced tumor cell killing by ultrasound after microtubule depolymerization. Bioeng Transl Med 2021; 6:e10233. [PMID: 34589605 PMCID: PMC8459596 DOI: 10.1002/btm2.10233] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [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: 03/21/2021] [Revised: 05/21/2021] [Accepted: 05/23/2021] [Indexed: 11/24/2022] Open
Abstract
Recent studies show that tumor cells are vulnerable to mechanical stresses and undergo calcium-dependent apoptosis (mechanoptosis) with mechanical perturbation by low-frequency ultrasound alone. To determine if tumor cells are particularly sensitive to mechanical stress in certain phases of the cell cycle, inhibitors of the cell-cycle phases are tested for effects on mechanoptosis. Most inhibitors show no significant effect, but inhibitors of mitosis that cause microtubule depolymerization increase the mechanoptosis. Surprisingly, ultrasound treatment also disrupts microtubules independent of inhibitors in tumor cells but not in normal cells. Ultrasound causes calcium entry through mechanosensitive Piezo1 channels that disrupts microtubules via calpain protease activation. Myosin IIA contractility is required for ultrasound-mediated mechanoptosis and microtubule disruption enhances myosin IIA contractility through activation of GEF-H1 and RhoA pathway. Further, ultrasound promotes contractility-dependent Piezo1 expression and localization to the peripheral adhesions where activated Piezo1 allows calcium entry to continue feedback loop. Thus, the synergistic action of ultrasound and nanomolar concentrations of microtubule depolymerizing agents can enhance tumor therapies.
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Affiliation(s)
- Aditi Singh
- Mechanobiology InstituteNational University of SingaporeSingapore
- Department of PharmacyBirla Institute of Technology and SciencePilaniIndia
| | - Ajay Tijore
- Mechanobiology InstituteNational University of SingaporeSingapore
| | - Felix Margadant
- Mechanobiology InstituteNational University of SingaporeSingapore
| | - Chloe Simpson
- Mechanobiology InstituteNational University of SingaporeSingapore
| | - Deepak Chitkara
- Department of PharmacyBirla Institute of Technology and SciencePilaniIndia
| | - Boon Chuan Low
- Mechanobiology InstituteNational University of SingaporeSingapore
| | - Michael Sheetz
- Mechanobiology InstituteNational University of SingaporeSingapore
- Biochemistry and Molecular Biology DepartmentUniversity of Texas Medical BranchGalvestonTexasUSA
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Hu X, Jalal S, Sheetz M, Bakke O, Margadant F. Correction: Micro-stepping extended focus reduces photobleaching and preserves structured illumination super-resolution features. J Cell Sci 2021; 134:269271. [PMID: 34169963 DOI: 10.1242/jcs.258884] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Tijore A, Yao M, Wang YH, Hariharan A, Nematbakhsh Y, Lee Doss B, Lim CT, Sheetz M. Selective killing of transformed cells by mechanical stretch. Biomaterials 2021; 275:120866. [PMID: 34044258 DOI: 10.1016/j.biomaterials.2021.120866] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [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: 02/18/2021] [Revised: 04/13/2021] [Accepted: 04/30/2021] [Indexed: 12/12/2022]
Abstract
Cancer cells differ from normal cells in several important features like anchorage independence, Warburg effect and mechanosensing. Further, in recent studies, they respond aberrantly to external mechanical distortion. Consistent with altered mechano-responsiveness, we find that cyclic stretching of tumor cells from many different tissues reduces growth rate and causes apoptosis on soft surfaces. Surprisingly, normal cells behave similarly when transformed by depletion of the rigidity sensor protein (Tropomyosin 2.1). Restoration of rigidity sensing in tumor cells promotes rigidity dependent mechanical behavior, i.e. cyclic stretching enhances growth and reduces apoptosis on soft surfaces. The mechanism of mechanical apoptosis (mechanoptosis) of transformed cells involves calcium influx through the mechanosensitive channel, Piezo1 that activates calpain 2 dependent apoptosis through the BAX molecule and subsequent mitochondrial activation of caspase 3 on both fibronetin and collagen matrices. Thus, it is possible to selectively kill tumor cells by mechanical perturbations, while stimulating the growth of normal cells.
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Affiliation(s)
- Ajay Tijore
- Mechanobiology Institute, National University of Singapore, 117411, Singapore
| | - Mingxi Yao
- Mechanobiology Institute, National University of Singapore, 117411, Singapore
| | - Yu-Hsiu Wang
- Mechanobiology Institute, National University of Singapore, 117411, Singapore
| | - Anushya Hariharan
- Mechanobiology Institute, National University of Singapore, 117411, Singapore
| | - Yasaman Nematbakhsh
- Department of Biomedical Engineering, National University of Singapore, 117575, Singapore
| | - Bryant Lee Doss
- Mechanobiology Institute, National University of Singapore, 117411, Singapore
| | - Chwee Teck Lim
- Mechanobiology Institute, National University of Singapore, 117411, Singapore; Department of Biomedical Engineering, National University of Singapore, 117575, Singapore; Institute for Health Innovation and Technology, National University of Singapore, 117599, Singapore
| | - Michael Sheetz
- Mechanobiology Institute, National University of Singapore, 117411, Singapore; Molecular Mechanomedicine Program, Biochemistry and Molecular Biology Department, University of Texas Medical Branch, Galveston, TX, USA.
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Vink J, Yu V, Dahal S, Lohner J, Stern-Asher C, Mourad M, Davis G, Xue Z, Wang S, Myers K, Kitajewski J, Chen X, Wapner RJ, Ananth CV, Sheetz M, Gallos G. Extracellular Matrix Rigidity Modulates Human Cervical Smooth Muscle Contractility-New Insights into Premature Cervical Failure and Spontaneous Preterm Birth. Reprod Sci 2021; 28:237-251. [PMID: 32700284 PMCID: PMC9344974 DOI: 10.1007/s43032-020-00268-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 07/15/2020] [Indexed: 12/16/2022]
Abstract
Spontaneous preterm birth (sPTB), a major cause of infant morbidity and mortality, must involve premature cervical softening/dilation for a preterm vaginal delivery to occur. Yet, the mechanism behind premature cervical softening/dilation in humans remains unclear. We previously reported the non-pregnant human cervix contains considerably more cervical smooth muscle cells (CSMC) than historically appreciated and the CSMC organization resembles a sphincter. We hypothesize that premature cervical dilation leading to sPTB may be due to (1) an inherent CSMC contractility defect resulting in sphincter failure and/or (2) altered cervical extracellular matrix (ECM) rigidity which influences CSMC contractility. To test these hypotheses, we utilized immunohistochemistry to confirm this CSMC phenotype persists in the human pregnant cervix and then assessed in vitro arrays of contractility (F:G actin ratios, PDMS pillar arrays) using primary CSMC from pregnant women with and without premature cervical failure (PCF). We show that CSMC from pregnant women with PCF do not have an inherent CSMC contractility defect but that CSMC exhibit decreased contractility when exposed to soft ECM. Given this finding, we used UPLC-ESI-MS/MS to evaluate collagen cross-link profiles in the cervical tissue from non-pregnant women with and without PCF and found that women with PCF have decreased collagen cross-link maturity ratios, which correlates to softer cervical tissue. These findings suggest having soft cervical ECM may lead to decreased CSMC contractile tone and a predisposition to sphincter laxity that contributes to sPTB. Further studies are needed to explore the interaction between cervical ECM properties and CSMC cellular behavior when investigating the pathophysiology of sPTB.
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Affiliation(s)
- Joy Vink
- Department of Obstetrics and Gynecology, Columbia University Irving Medical Center, 622 West 168th St. PH16-66, New York, NY, 10032, USA.
- Preterm Birth Prevention Center, Columbia University Irving Medical Center, New York, NY, USA.
| | - Victoria Yu
- Department of Obstetrics and Gynecology, Columbia University Irving Medical Center, 622 West 168th St. PH16-66, New York, NY, 10032, USA
| | - Sudip Dahal
- Department of Obstetrics and Gynecology, Columbia University Irving Medical Center, 622 West 168th St. PH16-66, New York, NY, 10032, USA
| | - James Lohner
- Department of Biological Sciences, Columbia University, New York, NY, USA
| | - Conrad Stern-Asher
- Department of Obstetrics and Gynecology, Columbia University Irving Medical Center, 622 West 168th St. PH16-66, New York, NY, 10032, USA
| | - Mirella Mourad
- Department of Obstetrics and Gynecology, Columbia University Irving Medical Center, 622 West 168th St. PH16-66, New York, NY, 10032, USA
- Preterm Birth Prevention Center, Columbia University Irving Medical Center, New York, NY, USA
| | - George Davis
- Department of Obstetrics and Gynecology, Rowan University School of Osteopathic Medicine, Camden, NJ, USA
| | - Zenghui Xue
- Mailman School of Public Health, Columbia University, New York, NY, USA
| | - Shuang Wang
- Mailman School of Public Health, Columbia University, New York, NY, USA
| | - Kristin Myers
- Department of Mechanical Engineering, Columbia University, New York, NY, USA
| | - Jan Kitajewski
- Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, IL, USA
| | - Xiaowei Chen
- Department of Pathology, Columbia University Irving Medical Center, New York, NY, USA
| | - Ronald J Wapner
- Department of Obstetrics and Gynecology, Columbia University Irving Medical Center, 622 West 168th St. PH16-66, New York, NY, 10032, USA
| | - Cande V Ananth
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Division of Epidemiology and Biostatistics, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ, USA
- Department of Biostatistics and Epidemiology, Rutgers School of Public Health, Piscataway, NJ, USA
- Environmental and Occupational Health Sciences Institute, Rutgers Robert Wood Johnson Medical School, Piscataway, NJ, USA
| | - Michael Sheetz
- Department of Biological Sciences, Columbia University, New York, NY, USA
| | - George Gallos
- Department of Anesthesiology, Columbia University Medical Center, New York, NY, USA
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9
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Hu X, Jalal S, Sheetz M, Bakke O, Margadant F. Micro-stepping extended focus reduces photobleaching and preserves structured illumination super-resolution features. J Cell Sci 2020; 133:jcs240796. [PMID: 32265275 DOI: 10.1242/jcs.240796] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Accepted: 03/24/2020] [Indexed: 08/31/2023] Open
Abstract
Despite progress made in confocal microscopy, even fast systems still have insufficient temporal resolution for detailed live-cell volume imaging, such as tracking rapid movement of membrane vesicles in three-dimensional space. Depending on the shortfall, this may result in undersampling and/or motion artifacts that ultimately limit the quality of the imaging data. By sacrificing detailed information in the Z-direction, we propose a new imaging modality that involves capturing fast 'projections' from the field of depth and shortens imaging time by approximately an order of magnitude as compared to standard volumetric confocal imaging. With faster imaging, radiation exposure to the sample is reduced, resulting in less fluorophore photobleaching and potential photodamage. The implementation minimally requires two synchronized control signals that drive a piezo stage and trigger the camera exposure. The device generating the signals has been tested on spinning disk confocal and instant structured-illumination-microscopy (iSIM) microscopes. Our calibration images show that the approach provides highly repeatable and stable imaging conditions that enable photometric measurements of the acquired data, in both standard live imaging and super-resolution modes.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Xian Hu
- Department of Biosciences, University of Oslo, Blindern, 0371 Oslo, Norway
| | - Salma Jalal
- Mechanobiology Institute, National University of Singapore, Singapore 117411
| | - Michael Sheetz
- Mechanobiology Institute, National University of Singapore, Singapore 117411
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Oddmund Bakke
- Department of Biosciences, University of Oslo, Blindern, 0371 Oslo, Norway
| | - Felix Margadant
- Mechanobiology Institute, National University of Singapore, Singapore 117411
- Department of Biomedical Engineering, National University of Singapore, Singapore 117583
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10
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Abstract
For many years, major differences in morphology, motility, and mechanical characteristics have been observed between transformed cancer and normal cells. In this review, we consider these differences as linked to different states of normal and transformed cells that involve distinct mechanosensing and motility pathways. There is a strong correlation between repeated tissue healing and/or inflammation and the probability of cancer, both of which involve growth in adult tissues. Many factors are likely needed to enable growth, including the loss of rigidity sensing, but recent evidence indicates that microRNAs have important roles in causing the depletion of growth-suppressing proteins. One microRNA, miR-21, is overexpressed in many different tissues during both healing and cancer. Normal cells can become transformed by the depletion of cytoskeletal proteins that results in the loss of mechanosensing, particularly rigidity sensing. Conversely, the transformed state can be reversed by the expression of cytoskeletal proteins-without direct alteration of hormone receptor levels. In this review, we consider the different stereotypical forms of motility and mechanosensory systems. A major difference between normal and transformed cells involves a sensitivity of transformed cells to mechanical perturbations. Thus, understanding the different mechanical characteristics of transformed cells may enable new approaches to treating wound healing and cancer.
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Affiliation(s)
- Michael Sheetz
- Mechanobiology Institute and Department of Biological Sciences, National University of Singapore, Singapore 117411
- Molecular MechanoMedicine Program and Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas 77555, USA;
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11
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Vink J, Dahal S, Li H, Mourad M, Ndubisi C, Myers K, Kitajewski J, Sheetz M, Wapner R, Gallos G. 557: Progesterone decreases human cervical smooth muscle cell contractility. Am J Obstet Gynecol 2019. [DOI: 10.1016/j.ajog.2018.11.579] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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12
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Sheetz M, Steiner C. Compliance with the U.S. Nuclear Regulatory Commission Revised Licensing Guidance for Radioactive Seed Localization. Health Phys 2018; 115:402-408. [PMID: 30045125 DOI: 10.1097/hp.0000000000000889] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The use of radioactive seed localization (RSL) as a reliable alternative to wire localization (WL) for guiding the surgical excision of non-palpable lesions has become more popular because of its demonstrated advantages for both the patient and surgeon. RSL is regulated under 10 CFR 35.1000 (Other Medical Uses) for which the U.S. Nuclear Regulatory Commission (U.S. NRC) issued its original licensing guidance entitled "I-125 and Pd-103 Low Dose Rate Brachytherapy Seeds Used for Localization of Non-palpable Lesions" in 2006. At that time, RSL was performed as an off-label use of the same radioactive I seeds used for brachytherapy, so the focus of this initial guidance was to establish the same requirements for RSL as for brachytherapy. Strict compliance with the licensing guidance was burdensome and made it difficult for some licensees to implement an RSL program. In response to a request from the user community and recommendations from an Advisory Committee on the Medical Use of Isotopes (ACMUI) subcommittee, the U.S. NRC formed a working group to consider revisions to its RSL guidance to make it more relevant to the conduct of the procedure. On October 7, 2016, the U.S. NRC issued a revised licensing guidance document titled "Low Activity Radioactive Seeds Used for Localization of Non-Palpable Lesions and Lymph Nodes." This manuscript highlights the changes in the latest U.S. NRC licensing guidance for RSL, including authorized user training and experience, written directives, surveys, instrumentation, and medical event criteria, and presents practical ways to satisfy the new requirements.
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Affiliation(s)
- Michael Sheetz
- 1University of Pittsburgh, Radiation Safety Office, 3500 Fifth Avenue, Suite 400, Pittsburgh, PA 15213
| | - Cynthia Steiner
- University of Pittsburgh, Radiation Safety Office, 3500 Fifth Avenue, Suite 400, Pittsburgh, PA 15213
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13
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Karni-Schmidt O, Friedler A, Zupnick A, McKinney K, Mattia M, Beckerman R, Bouvet P, Sheetz M, Fersht A, Prives C. Correction: Energy-dependent nucleolar localization of p53 in vitro requires two discrete regions within the p53 carboxyl terminus. Oncogene 2018; 37:4901-4902. [PMID: 30068941 DOI: 10.1038/s41388-018-0321-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Following the publication of this article the authors noted that two images were duplicated in Figure 2B. The corrected figure 2B is below. The authors wish to apologize for any inconvenience caused.
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Affiliation(s)
- O Karni-Schmidt
- Department of Biological Sciences, Columbia University, New York, USA
| | - A Friedler
- Department of MRC-CPE, Center for Protein Engineering, Medical Research Council, Cambridge, UK.,Department of Organic Chemistry, The Hebrew University of Jerusalem, Givat Ram, Jerusalem, Israel
| | - A Zupnick
- Department of Biological Sciences, Columbia University, New York, USA
| | - K McKinney
- Department of Biological Sciences, Columbia University, New York, USA
| | - M Mattia
- Department of Biological Sciences, Columbia University, New York, USA
| | - R Beckerman
- Department of Biological Sciences, Columbia University, New York, USA
| | - P Bouvet
- Laboratoire de Biologie Mole´culaire de la Cellule/UMR 5161, Ecole Normale Supe´rieure de Lyon 46, Alle´e d'Italie, 69364, Lyon Cedex, France
| | - M Sheetz
- Department of Biological Sciences, Columbia University, New York, USA
| | - A Fersht
- Department of MRC-CPE, Center for Protein Engineering, Medical Research Council, Cambridge, UK
| | - C Prives
- Department of Biological Sciences, Columbia University, New York, USA.
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Pandey P, Hawkes W, Hu J, Megone WV, Gautrot J, Anilkumar N, Zhang M, Hirvonen L, Cox S, Ehler E, Hone J, Sheetz M, Iskratsch T. Cardiomyocytes Sense Matrix Rigidity through a Combination of Muscle and Non-muscle Myosin Contractions. Dev Cell 2018; 45:661. [PMID: 29870723 PMCID: PMC5988560 DOI: 10.1016/j.devcel.2018.05.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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15
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Ring J, Tupin E, Elder D, Hiatt J, Sheetz M, Kirner N, Little C. Health Physics Society Comments to U.S. Environmental Protection Agency Regulatory Reform Task Force. Health Phys 2018; 114:507-510. [PMID: 29505431 DOI: 10.1097/hp.0000000000000809] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The Health Physics Society (HPS) provided comment to the U.S. Environmental Protection Agency (EPA) on options to consider when developing an action plan for President Trump's Executive Order to evaluate regulations for repeal, replacement, or modification. The HPS recommended that the EPA reconsider their adherence to the linear no-threshold (LNT) model for radiation risk calculations and improve several documents by better addressing uncertainties in low-dose, low dose-rate (LDDR) radiation exposure environments. The authors point out that use of the LNT model near background levels cannot provide reliable risk projections, use of the LNT model and collective-dose calculations in some EPA documents is inconsistent with the recommendations of international organizations, and some EPA documents have not been exposed to the public comment rule-making process. To assist in establishing a better scientific basis for the risks of low dose rate and low dose radiation exposure, the EPA should continue to support the "Million Worker Study," led by the National Council on Radiation Protection and Measurement.
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Affiliation(s)
- Joseph Ring
- *Beth Israel Deaconess Medical Center, Kirstein B324, 330 Brookline Avenue, Boston, MA 02115
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16
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Chen Z, Oh D, Dubey AK, Yao M, Yang B, Groves JT, Sheetz M. EGFR family and Src family kinase interactions: mechanics matters? Curr Opin Cell Biol 2018; 51:97-102. [DOI: 10.1016/j.ceb.2017.12.003] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Accepted: 12/11/2017] [Indexed: 01/23/2023]
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17
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Yecies T, Semins M, Sheetz M, Durango M, Chaudhry R. MP63-05 FLUOROSCOPY PULSE RATE AND RADIATION ABSORBED DOSE DEMONSTRATE A NEAR-PERFECT LINEAR CORRELATION. J Urol 2018. [DOI: 10.1016/j.juro.2018.02.2028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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18
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Yu M, Yuan X, Sheetz M, Bershadsky A, Yan J. MDIA1 Senses Both Force and Torque during F-actin Filament Polymerisation. Biophys J 2018. [DOI: 10.1016/j.bpj.2017.11.808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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19
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Mourad M, Qin S, Ananth CV, Fu A, Yoshida K, Myers K, Kitajewski J, Shawber C, Wapner R, Sheetz M, Vink J. 109: Human cervical smooth muscle stretch increases pro-inflammatory cytokine secretion. Am J Obstet Gynecol 2017. [DOI: 10.1016/j.ajog.2016.11.999] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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20
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Abstract
Recent studies at the nanometer scale have revealed that relatively uniform clusters of adhesion proteins (50-100 nm) constitute the modular units of cell adhesion sites in both cell-matrix and cell-cell adhesions. Super resolution microscopy and membrane protein diffusion studies both suggest that even large focal adhesions are formed of 100 nm clusters that are loosely aggregated. Clusters of 20-50 adhesion molecules (integrins or cadherins) can support large forces through avidity binding interactions but can also be disassembled or endocytosed rapidly. Assembly of the clusters of integrins is force-independent and involves gathering integrins at ligand binding sites where they are stabilized by cytoplasmic adhesion proteins that crosslink the integrin cytoplasmic tails plus connect the clusters to the cell cytoskeleton. Cooperative-signaling events can occur in a single cluster without cascading to other clusters. Thus, the clusters appear to be very important elements in many cellular processes and can be considered as a critical functional module.
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Affiliation(s)
- Rishita Changede
- Mechanobiology Institute, National University of Singapore, Singapore, Singapore
| | - Michael Sheetz
- Mechanobiology Institute, National University of Singapore, Singapore, Singapore
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21
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Berger RP, Panigrahy A, Gottschalk S, Sheetz M. Effective Radiation Dose in a Skeletal Survey Performed for Suspected Child Abuse. J Pediatr 2016; 171:310-2. [PMID: 26831745 DOI: 10.1016/j.jpeds.2016.01.017] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 12/10/2015] [Accepted: 01/05/2016] [Indexed: 11/26/2022]
Abstract
Effective dose of a skeletal survey in infants using digital radiography was estimated to be 0.2 mSv using Monte Carlo simulation. Radiation risk from this procedure is, therefore, low. Radiation concern should not be an overriding factor when deciding whether skeletal survey is needed in cases of possible physical abuse.
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Affiliation(s)
- Rachel P Berger
- Department of Pediatrics, Children's Hospital of Pittsburgh of the University of Pittsburgh Medical Center, Safar Center for Resuscitation Research, University of Pittsburgh, Pittsburgh, PA.
| | - Ashok Panigrahy
- Department Radiology, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, PA
| | - Shawn Gottschalk
- Department Radiology, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, PA
| | - Michael Sheetz
- Department of Radiation Safety, University of Pittsburgh, Pittsburgh, PA
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Abstract
Guest editors G. V. Shivashankar, Michael Sheetz and Paul Matsudaira introduce the Mechanobiology themed issue of Integrative Biology.
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Affiliation(s)
- G. V. Shivashankar
- Mechanobiology Institute
- National University of Singapore
- Singapore 117411
- Department of Biological Sciences
- National University of Singapore
| | - Michael Sheetz
- Mechanobiology Institute
- National University of Singapore
- Singapore 117411
- Department of Biological Sciences
- Columbia University
| | - Paul Matsudaira
- Mechanobiology Institute
- National University of Singapore
- Singapore 117411
- Centre for Bio-Imaging Sciences
- Department of Biological Sciences
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Low BC, Pan CQ, Shivashankar GV, Bershadsky A, Sudol M, Sheetz M. YAP/TAZ as mechanosensors and mechanotransducers in regulating organ size and tumor growth. FEBS Lett 2014; 588:2663-70. [PMID: 24747426 DOI: 10.1016/j.febslet.2014.04.012] [Citation(s) in RCA: 294] [Impact Index Per Article: 29.4] [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: 03/10/2014] [Revised: 04/05/2014] [Accepted: 04/07/2014] [Indexed: 02/06/2023]
Abstract
Organ size is controlled by the concerted action of biochemical and physical processes. Although mechanical forces are known to regulate cell and tissue behavior, as well as organogenesis, the precise molecular events that integrate mechanical and biochemical signals to control these processes are not fully known. The recently delineated Hippo-tumor suppressor network and its two nuclear effectors, YAP and TAZ, shed light on these mechanisms. YAP and TAZ are proto-oncogene proteins that respond to complex physical milieu represented by the rigidity of the extracellular matrix, cell geometry, cell density, cell polarity and the status of the actin cytoskeleton. Here, we review the current knowledge of how YAP and TAZ function as mechanosensors and mechanotransducers. We also suggest that by deciphering the mechanical and biochemical signals controlling YAP/TAZ function, we will gain insights into new strategies for cancer treatment and organ regeneration.
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Affiliation(s)
- Boon Chuan Low
- Mechanobiology Institute, National University of Singapore, 5A Engineering Drive, 117411, Republic of Singapore; Cell Signaling and Developmental Biology Laboratory, Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, 117543, Republic of Singapore.
| | - Catherine Qiurong Pan
- Mechanobiology Institute, National University of Singapore, 5A Engineering Drive, 117411, Republic of Singapore
| | - G V Shivashankar
- Mechanobiology Institute, National University of Singapore, 5A Engineering Drive, 117411, Republic of Singapore
| | - Alexander Bershadsky
- Mechanobiology Institute, National University of Singapore, 5A Engineering Drive, 117411, Republic of Singapore; Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Marius Sudol
- Mechanobiology Institute, National University of Singapore, 5A Engineering Drive, 117411, Republic of Singapore
| | - Michael Sheetz
- Mechanobiology Institute, National University of Singapore, 5A Engineering Drive, 117411, Republic of Singapore; Department of Biological Sciences, Columbia University, New York, NY 10027, USA.
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Iskratsch T, Yu CH, Mathur A, Liu S, Stévenin V, Dwyer J, Hone J, Ehler E, Sheetz M. FHOD1 is needed for directed forces and adhesion maturation during cell spreading and migration. Dev Cell 2014; 27:545-59. [PMID: 24331927 DOI: 10.1016/j.devcel.2013.11.003] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Revised: 10/19/2013] [Accepted: 11/04/2013] [Indexed: 01/13/2023]
Abstract
Matrix adhesions provide critical signals for cell growth or differentiation. They form through a number of distinct steps that follow integrin binding to matrix ligands. In an early step, integrins form clusters that support actin polymerization by an unknown mechanism. This raises the question of how actin polymerization occurs at the integrin clusters. We report here that a major formin in mouse fibroblasts, FHOD1, is recruited to integrin clusters, resulting in actin assembly. Using cell-spreading assays on lipid bilayers, solid substrates, and high-resolution force-sensing pillar arrays, we find that knockdown of FHOD1 impairs spreading, coordinated application of adhesive force, and adhesion maturation. Finally, we show that targeting of FHOD1 to the integrin sites depends on the direct interaction with Src family kinases and is upstream of the activation by Rho kinase. Thus, our findings provide insights into the mechanisms of cell migration with implications for development and disease.
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Affiliation(s)
- Thomas Iskratsch
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA.
| | - Cheng-Han Yu
- Mechanobiology Institute, National University of Singapore, Singapore 117411, Singapore
| | - Anurag Mathur
- Department of Mechanical Engineering, Columbia University, New York, NY 10027, USA
| | - Shuaimin Liu
- Department of Mechanical Engineering, Columbia University, New York, NY 10027, USA
| | - Virginie Stévenin
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
| | - Joseph Dwyer
- Randall Division of Cell and Molecular Biophysics and Cardiovascular Division, King's College London, London SE1 1UL, UK
| | - James Hone
- Department of Mechanical Engineering, Columbia University, New York, NY 10027, USA
| | - Elisabeth Ehler
- Randall Division of Cell and Molecular Biophysics and Cardiovascular Division, King's College London, London SE1 1UL, UK
| | - Michael Sheetz
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA; Mechanobiology Institute, National University of Singapore, Singapore 117411, Singapore.
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Iskratsch T, Yu CH, Mathur A, Liu S, Stévenin V, Dwyer J, Hone J, Ehler E, Sheetz M. FHOD1 at Early Integrin Adhesions Drives Cell Spreading. Biophys J 2014. [DOI: 10.1016/j.bpj.2013.11.929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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26
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Sheetz M. Mechanosensing by Tropomyosin-Controlled Myosin Contractions. Biophys J 2014. [DOI: 10.1016/j.bpj.2013.11.121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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27
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Thiyagarajan S, Stachowiak M, Meacci G, Sheetz M, O'Shaughnessy B. Lateral Waves during Protrusion-Retraction Cycles of Migrating Cells are Propagating Cracks. Biophys J 2014. [DOI: 10.1016/j.bpj.2013.11.2035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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28
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Gupta P, Gauthier NC, Cheng-Han Y, Zuanning Y, Pontes B, Ohmstede M, Martin R, Knölker HJ, Döbereiner HG, Krendel M, Sheetz M. Myosin 1E localizes to actin polymerization sites in lamellipodia, affecting actin dynamics and adhesion formation. Biol Open 2013; 2:1288-99. [PMID: 24337113 PMCID: PMC3863413 DOI: 10.1242/bio.20135827] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [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] [Indexed: 01/08/2023] Open
Abstract
Because the actin network in active lamellipodia is continuously assembling at the edge, moving inward and disassembling, there is a question as to how actin-binding proteins and other components are transported to the leading edge and how nascent adhesions are stabilized. Active transport could play a significant role in these functions but the components involved are unknown. We show here that Myosin 1E (a long tailed Myosin 1 isoform) rapidly moves to the tips of active lamellipodia and to actin-rich early adhesions, unlike Myosin 1G, 1B or 1C (short tailed isoforms). Myosin 1E co-localizes with CARMIL, FHOD1, Arp3 and β3-integrin in those early adhesions. But these structures precede stable paxillin-rich adhesions. Myosin 1E movement depends upon actin-binding domains and the presence of an SH3 oligomerization domain. Overexpression of a Myosin 1E deletion mutant without the extreme C-terminal interacting (SH3) domain (Myosin 1EΔSH3) increases edge fluctuations and decreases stable adhesion lifetimes. In contrast, overexpression of Myosin 1E full tail domain (TH1+TH2+TH3/SH3) decreases edge fluctuation. In Myosin 1E knockdown cells, and more prominently in cells treated with Myosin 1 inhibitor, cell-matrix adhesions are also short-lived and fail to mature. We suggest that, by moving to actin polymerization sites and early adhesion sites in active lamellipodia, Myosin 1E might play important roles in transporting not only important polymerizing proteins but also proteins involved in adhesion stabilization.
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Affiliation(s)
- Prabuddha Gupta
- Mechanobiology Institute, National University of Singapore, Singapore 117411
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29
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Yu L, Lu W, Ye C, Wang Z, Zhong M, Chai Q, Sheetz M, Wei Y. Role of a conserved residue R780 in Escherichia coli multidrug transporter AcrB. Biochemistry 2013; 52:6790-6. [PMID: 24007302 DOI: 10.1021/bi400452v] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Multidrug efflux pumps play important roles in bacteria drug resistance. A major multidrug efflux system in Gram-negative bacteria is composed of the inner membrane transporter AcrB, outer membrane protein channel TolC, and membrane fusion protein AcrA. These three proteins form a large complex that spans both layers of cell membranes and the periplasmic space. AcrB exists and functions as a homotrimer. To identify residues at the trimer interface that play important roles in AcrB function, we conducted site directed mutagenesis and discovered a key residue, R780. Although R780K was partially functional, all other R780 mutants tested were completely nonfunctional. Replacement of R780 by other residues disrupted trimer association. However, a decrease of trimer stability was not the lone cause for the observed loss of activity, because the activity loss could not be restored by strengthening trimer interaction. Using both heat and chemical denaturation methods, we found that the mutation decreased protein stability. Finally, we identified a repressor mutation, M774K, through random mutagenesis. It restored the activity of AcrBR780A to a level close to that of the wild-type protein. To examine the mechanism of activity restoration, we monitored denaturation of AcrBR780A/M774K and found that the repressor mutation improved protein stability. These results suggest that R780 is critical for AcrB stability. When R780 was replaced by Ala, the protein retained the overall structure, still trimerized in the cell membrane, and interacted with AcrA. However, local structural rearrangement might have occurred and lead to the decrease of protein stability and loss of substrate efflux activity.
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Affiliation(s)
- Linliang Yu
- Department of Chemistry, University of Kentucky ,Lexington, Kentucky 40506, United States
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30
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Meacci G, Stachowiak M, Liu S, Iskratsch T, Mathur A, Wolfenson H, Ghassemi S, Roca-Cusachs P, Tabdanov E, Gauthier N, Gondarenko A, O'Shaughnessy B, Hone J, Sheetz M. Sarcomere-Like Units Contract Cell Edges. Biophys J 2013. [DOI: 10.1016/j.bpj.2012.11.2639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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31
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Pan CQ, Sudol M, Sheetz M, Low BC. Modularity and functional plasticity of scaffold proteins as p(l)acemakers in cell signaling. Cell Signal 2012; 24:2143-65. [PMID: 22743133 DOI: 10.1016/j.cellsig.2012.06.002] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Revised: 05/22/2012] [Accepted: 06/16/2012] [Indexed: 01/14/2023]
Abstract
Cells coordinate and integrate various functional modules that control their dynamics, intracellular trafficking, metabolism and gene expression. Such capacity is mediated by specific scaffold proteins that tether multiple components of signaling pathways at plasma membrane, Golgi apparatus, mitochondria, endoplasmic reticulum, nucleus and in more specialized subcellular structures such as focal adhesions, cell-cell junctions, endosomes, vesicles and synapses. Scaffold proteins act as "pacemakers" as well as "placemakers" that regulate the temporal, spatial and kinetic aspects of protein complex assembly by modulating the local concentrations, proximity, subcellular dispositions and biochemical properties of the target proteins through the intricate use of their modular protein domains. These regulatory mechanisms allow them to gate the specificity, integration and crosstalk of different signaling modules. In addition to acting as physical platforms for protein assembly, many professional scaffold proteins can also directly modify the properties of their targets while they themselves can be regulated by post-translational modifications and/or mechanical forces. Furthermore, multiple scaffold proteins can form alliances of higher-order regulatory networks. Here, we highlight the emerging themes of scaffold proteins by analyzing their common and distinctive mechanisms of action and regulation, which underlie their functional plasticity in cell signaling. Understanding these mechanisms in the context of space, time and force should have ramifications for human physiology and for developing new therapeutic approaches to control pathological states and diseases.
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Affiliation(s)
- Catherine Qiurong Pan
- Cell Signaling and Developmental Biology Laboratory, Department of Biological Sciences, National University of Singapore, Republic of Singapore.
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32
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Chen H, Zhu X, Wang Y, Sheetz M, Nakamura F, Yan J. Differential Mechanical Stability of Filamin a Rod Segments and Domain Pair Interaction. Biophys J 2012. [DOI: 10.1016/j.bpj.2011.11.950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022] Open
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33
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Margadant F, Chew LL, Hu X, Yu H, Bate N, Zhang X, Sheetz M. Mechanotransduction in vivo by repeated talin stretch-relaxation events depends upon vinculin. PLoS Biol 2011; 9:e1001223. [PMID: 22205879 PMCID: PMC3243729 DOI: 10.1371/journal.pbio.1001223] [Citation(s) in RCA: 154] [Impact Index Per Article: 11.8] [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: 11/06/2010] [Accepted: 11/10/2011] [Indexed: 01/13/2023] Open
Abstract
The focal adhesion protein talin undergoes cycles of stretching and relaxation in living cells, suggesting a role in the transduction of mechanical into biochemical signals. Mechanotransduction is a critical function for cells, in terms of cell viability, shaping of tissues, and cellular behavior. In vitro, cellular level forces can stretch adhesion proteins that link extracellular matrix to the actin cytoskeleton exposing hidden binding sites. However, there is no evidence that in vivo forces produce significant in vivo stretching to cause domain unfolding. We now report that the adhesion protein, talin, is repeatedly stretched by 100–350 nm in vivo by myosin contraction of actin filaments. Using a functional EGFP-N-Talin1-C-mCherry to measure the length of single talin molecules, we observed that the C-terminal mCherry was normally displaced in the direction of actin flow by 90 to >250 nm from N-EGFP but only by 50–60 nm (talin's length in vitro) after myosin inhibition. Individual talin molecules transiently stretched and relaxed. Peripheral, multimolecular adhesions had green outside and red proximal edges. They also exhibited transient, myosin-dependent stretching of 50–350 nm for 6–16 s; however, expression of the talin-binding head of vinculin increased stretching to about 400 nm and suppressed dynamics. We suggest that rearward moving actin filaments bind, stretch, and release talin in multiple, stochastic stick-slip cycles and that multiple vinculin binding and release cycles integrate pulling on matrices into biochemical signals. How are mechanical forces that act on the surface of a cell transformed into biochemical signals within the cell? Studies of isolated proteins suggest that some of them can stretch, but whether this also happens in living cells remains unclear. In this study, we have been able to measure the stretching of single molecules of a cellular adhesion protein called talin in vivo by tagging each end of the protein with a different fluorescent marker and observing changes in the distance between the two markers with a new microscopic method. Talin is a large cellular protein that concentrates at sites where the cell attaches to the substratum and links integrins in the cell membrane to the actin filament network in the cell. In our study, a green tag at the integrin-binding site was close to the cell surface, whereas a red tag at the actin-binding site was displaced inward by actin flow. We observed repeated protein stretching to 5–8 times the native protein length and relaxation linked to the transduction process in living cells in culture. Individual molecules stretched for 6–16 seconds over ranges of 50–350 nm. Cell adhesion sites, where hundreds of talin molecules were displaced in concert, had similar dynamics. These cycles of stretching and relaxation required the contractile protein myosin. The head domain of vinculin—an adhesion site protein that binds strongly to the stretched talin—kept the adhesions stretched and blocked large oscillations in length. These observations indicate that there is repeated stretching of talin, and that adhesion proteins play a role in the transduction of mechanical signals into biochemical signals through binding and release of vinculin and possibly other focal adhesion proteins.
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Affiliation(s)
- Felix Margadant
- Research Centre of Excellence in Mechanobiology, National University of Singapore, Singapore.
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34
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Rangamani P, Fardin MA, Xiong Y, Lipshtat A, Rossier O, Sheetz M, Iyengar R. Membrane Feedback Controls Signaling Regulation of Cell Spreading. Biophys J 2011. [DOI: 10.1016/j.bpj.2010.12.2605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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35
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Chen H, Zhu X, Sheetz M, Nakamura F, Yan J. Filamin a Segments Respond Force Differently. Biophys J 2011. [DOI: 10.1016/j.bpj.2010.12.3430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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36
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Sheetz M, Swanson D, Yates B. Physical presence during gamma stereotactic radiosurgery. Health Phys 2009; 96:S11-S15. [PMID: 19125050 DOI: 10.1097/01.hp.0000334061.89160.7f] [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] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
During an invited visit to the University of Pittsburgh Medical Center (UPMC) gamma knife facility, officials from the Nuclear Regulatory Commission (NRC) observed what they considered as an apparent violation of the physical presence requirements specified in 10 CFR 35.615(f)(3). This event initiated an inspection and two different but related investigations by the NRC Office of Investigations (OI). Based on the NRC inspection and investigations, the NRC identified three apparent violations that were under consideration for escalated enforcement. The University of Pittsburgh (licensee) requested an Alternative Dispute Resolution (ADR) session with the NRC to resolve issues related to whether a violation occurred, the appropriate enforcement action, and the appropriate corrective action. As a result of the ADR mediation session, the licensee and NRC agreed to final disposition of this matter by way of a single violation of the regulatory requirement in 10 CFR 35.24(b), whereby the licensee's Radiation Safety Officer failed to ensure that the physical presence requirements of 10 CFR 35.615(f)(3) were consistently met and failed to ensure that written directives were consistently signed by the Authorized User in accordance with 10 CFR 35.32. In addition to corrective actions the licensee had already taken to prevent recurrence, it also agreed to inform other licensees in the industry of this event, so that they may learn from this incident and take appropriate actions to assure that these types of violations do not occur at their institutions.
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Affiliation(s)
- M Sheetz
- Radiation Safety Office, University of Pittsburgh, G-7 Parran Hall, 130 DeSoto Street, Pittsburgh, PA 15261, USA.
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37
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Karni-Schmidt O, Friedler A, Zupnick A, McKinney K, Mattia M, Beckerman R, Bouvet P, Sheetz M, Fersht A, Prives C. Energy-dependent nucleolar localization of p53 in vitro requires two discrete regions within the p53 carboxyl terminus. Oncogene 2007; 26:3878-91. [PMID: 17237827 DOI: 10.1038/sj.onc.1210162] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [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] [Indexed: 12/19/2022]
Abstract
The p53 tumor suppressor is a nucleocytoplasmic shuttling protein that is found predominantly in the nucleus of cells. In addition to mutation, abnormal p53 cellular localization is one of the mechanisms that inactivate p53 function. To further understand features of p53 that contribute to the regulation of its trafficking within the cell, we analysed the subnuclear localization of wild-type and mutant p53 in human cells that were either permeabilized with detergent or treated with the proteasome inhibitor MG132. We, here, show that either endogenously expressed or exogenously added p53 protein localizes to the nucleolus in detergent-permeabilized cells in a concentration- and ATP hydrolysis-dependent manner. Two discrete regions within the carboxyl terminus of p53 are essential for nucleolar localization in permeabilized cells. Similarly, localization of p53 to the nucleolus after proteasome inhibition in unpermeabilized cells requires sequences within the carboxyl terminus of p53. Interestingly, genotoxic stress markedly decreases the association of p53 with the nucleolus, and phosphorylation of p53 at S392, a site that is modified by such stress, partially impairs its nucleolar localization. The possible significance of these findings is discussed.
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Affiliation(s)
- O Karni-Schmidt
- Department of Biological Sciences, Columbia University, New York, USA
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38
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Abstract
We discuss herein the theory as well as some design considerations of magnetic tweezers. This method of generating force on magnetic particles bound to biological entities is shown to have a number of advantages over other techniques: forces are exerted in noncontact mode, they can be large in magnitude (order of 10 nanonewtons), and adjustable in direction, static or oscillatory. One apparatus built in our laboratory is described in detail, along with examples of experimental applications and results.
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Affiliation(s)
- Monica Tanase
- Department of Biological Sciences, Columbia University, New York, New York 10027, USA
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Kazda C, Bachmann O, Sheetz M, Zhi X, Davis MD, Milton RC, Aiello LP. Wirkung von Ruboxistaurin auf den Visusverlust bei Patienten mit diabetischer Retinopathie. DIABETOL STOFFWECHS 2007. [DOI: 10.1055/s-2007-982096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Abstract
The shapes of eukaryotic cells and ultimately the organisms that they form are defined by cycles of mechanosensing, mechanotransduction and mechanoresponse. Local sensing of force or geometry is transduced into biochemical signals that result in cell responses even for complex mechanical parameters such as substrate rigidity and cell-level form. These responses regulate cell growth, differentiation, shape changes and cell death. Recent tissue scaffolds that have been engineered at the micro- and nanoscale level now enable better dissection of the mechanosensing, transduction and response mechanisms.
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Affiliation(s)
- Viola Vogel
- Laboratory for Biologically Oriented Materials, Department of Materials, Swiss Federal Institute of Technology (ETH), Zurich, Wolfgang-Pauli-Strasse 10, ETH Hönggerberg, HCI F443, CH-8093 Zürich, Switzerland.
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Moses-Kolko EL, Meltzer CC, Helsel JC, Sheetz M, Mathis C, Ruszkiewicz J, Bogen D, Confer AL, Wisner KL. No interruption of lactation is needed after (11)C-WAY 100635 or (11)C-raclopride PET. J Nucl Med 2005; 46:1765. [PMID: 16204729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2023] Open
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Hahn J, Maier B, Haijema BJ, Sheetz M, Dubnau D. Transformation proteins and DNA uptake localize to the cell poles in Bacillus subtilis. Cell 2005; 122:59-71. [PMID: 16009133 PMCID: PMC4442496 DOI: 10.1016/j.cell.2005.04.035] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.0] [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: 02/23/2005] [Revised: 04/08/2005] [Accepted: 04/30/2005] [Indexed: 11/29/2022]
Abstract
The Gram-positive, rod-forming bacterium Bacillus subtilis efficiently binds and internalizes transforming DNA. The localization of several competence proteins, required for DNA uptake, has been studied using fluorescence microscopy. At least three proteins (ComGA, ComFA, and YwpH) are preferentially associated with the cell poles and appear to colocalize. This association is dynamic; the proteins accumulate at the poles as transformability develops and then delocalize as transformability wanes. DNA binding and uptake also occur preferentially at the cell poles, as shown using fluorescent DNA and in single-molecule experiments with laser tweezers. In addition to the prominent polar sites, the competence proteins also localize as foci in association with the lateral cell membrane, but this distribution does not exhibit the same temporal changes as the polar accumulation. The results suggest the regulated assembly and disassembly of a DNA-uptake machine at the cell poles.
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Affiliation(s)
- Jeanette Hahn
- Public Health Research Institute, 225 Warren Street, Newark, New Jersey 07103
| | - Berenike Maier
- Department of Biological Sciences, Columbia University, New York, New York 10027
| | - Bert Jan Haijema
- Public Health Research Institute, 225 Warren Street, Newark, New Jersey 07103
| | - Michael Sheetz
- Department of Biological Sciences, Columbia University, New York, New York 10027
| | - David Dubnau
- Public Health Research Institute, 225 Warren Street, Newark, New Jersey 07103
- Correspondence:
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Carr B, Sheetz M, Brown M, Torok F, McCook B, Zajko A, Collins L, France M. 90yttrium-labeled glass microspheres (therasphere) given to the hepatic artery for treatment of unresectable HCC: initial clinical experience. Eur J Cancer 2001. [DOI: 10.1016/s0959-8049(01)81641-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Sawada Y, Nakamura K, Doi K, Takeda K, Tobiume K, Saitoh M, Morita K, Komuro I, De Vos K, Sheetz M, Ichijo H. Rap1 is involved in cell stretching modulation of p38 but not ERK or JNK MAP kinase. J Cell Sci 2001; 114:1221-7. [PMID: 11228165 DOI: 10.1242/jcs.114.6.1221] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.9] [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: 11/20/2022] Open
Abstract
Mechanical force or mechanical stress modulates intracellular signal pathways, including the mitogen-activated protein kinase (MAP kinase) cascades. In our system, cell stretching activated and cell contraction inactivated all three MAP kinase pathways (MKK1/2-extracellular signal-regulated kinase (ERK), MKK4 (SEK1)-cJun N-terminal kinase (JNK) and MKK3/6-p38 pathways). However, little is known about the molecular mechanisms that link the mechanical force to the MAP kinase cascades. To test whether Ras and Rap1 are possible components in the stretch-activated MAP kinase pathways, we examined if Ras and Rap1 were activated by cell stretching and if inhibition of their activity decreased the stretch-enhanced MAP kinase activity. Rap1 was activated by cell stretching and inactivated by cell contraction, whereas Ras was inactivated by cell stretching and activated by cell contraction. Rap1GapII and SPA-1, downregulators of Rap1 activity, decreased the stretch-enhanced p38 activity, whereas a dominant-negative mutant of Ras (RasN17) did not inhibit the stretch-initiated activation of MAP kinases. Furthermore, overexpression of Rap1 enhanced p38 activity but not ERK or JNK activity. These results indicate that Rap1 is involved in transducing the stretch-initiated signal to the MKK3/6-p38 pathway, but not to the MEK1/2-ERK or the MKK4 (SEK1)/MKK7-JNK pathway. Thus, Rap1 plays a unique role in force-initiated signal transduction.
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Affiliation(s)
- Y Sawada
- Laboratory of Cell Signaling, Graduate School, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo 113-8549, Japan.
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Affiliation(s)
- C McGoldrick
- Department of Cell Biology, Duke University Medical Center, Durham, North Carolina 27710, USA
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Davies P, Anderton B, Kirsch J, Konnerth A, Nitsch R, Sheetz M. First one in, last one out: the role of gabaergic transmission in generation and degeneration. Prog Neurobiol 1998; 55:651-8. [PMID: 9670223 DOI: 10.1016/s0301-0082(98)00024-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [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: 02/08/2023]
Abstract
This paper is the result of discussions between scientists working in widely separated areas, united by an interest in the hippocampus. The discussions focused on the possible role of GABA in the development and maturation of the hippocampus and in neurodegeneration in Alzheimer's disease (AD). GABA neurons are among the first to differentiate in the hippocampus and the properties of GABA neurotransmission in the developing hippocampus are distinct from those in the adult. GABAergic transmission may play a role in the clustering and maturation of GABA receptors, as well as of receptors for other neurotransmitters. The development and maturation of synaptic connections involves changes in the organization of the cytoskeleton, and mechanical force generation is probably required to establish appropriate points of contact. This generation of force may require coupling of specific receptors to the cytoskeleton through specialized proteins. In AD, much of the developmental process is progressively unraveled in the hippocampus, as afferent fibers, most notably from entorhinal excitatory neurons and from basal forebrain cholinergic cells, degenerate. This denervation undoubtedly has consequences for receptor systems, dendritic morphology and the underlying cytoskeleton. GABA neurons remain in the AD hippocampus, and may actually contribute to abnormal firing and degeneration of remaining pyramidal neurons. This attempt to bring together data from different areas of research has allowed the development of a scheme which identifies significant specific gaps in our knowledge, which could be readily filled by focused experimental work.
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Affiliation(s)
- P Davies
- Department of Pathology, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
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Abstract
Growth cones are capable of advancing despite linkage to a stationary axonal cytoskeleton in chick and murine dorsal root ganglion neurites. Several lines of evidence point to the growth cone as the site of cytoskeletal elongation. Fast axonal transport is probably the means by which cytoskeletal elements or cofactors are rapidly moved through the axon. We report that direct, but reversible, inhibition of fast axonal transport with laser optical tweezers inhibits growth cone motility if cytoskeletal attachment to the cell body is maintained. Advancement ceases after a distance-dependent lag period which correlates with the rate of fast axonal transport. But severing the axonal cytoskeleton with the laser tweezers allows growth cones to advance considerably further. We suggest that axon elongation requires fast axonal transport but growth cone motility does not.
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Affiliation(s)
- C Martenson
- Department of Pathology, Duke University Medical Center, Durham, North Carolina 27710
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Sheetz M, Elson E, Kucik D. To flow or not to flow? Nature 1990; 345:28. [PMID: 2330048 DOI: 10.1038/345028a0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Corash LM, Sheetz M, Bieri JG, Bartsocas C, Moses S, Bashan N, Schulman JD. Chronic hemolytic anemia due to glucose-6-phosphate dehydrogenase deficiency or glutathione synthetase deficiency: the role of vitamin E in its treatment. Ann N Y Acad Sci 1982; 393:348-60. [PMID: 6959562 DOI: 10.1111/j.1749-6632.1982.tb31274.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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Corash L, Spielberg S, Bartsocas C, Boxer L, Steinherz R, Sheetz M, Egan M, Schlessleman J, Schulman JD. Reduced chronic hemolysis during high-dose vitamin E administration in Mediterranean-type glucose-6-phosphate dehydrogenase deficiency. N Engl J Med 1980; 303:416-20. [PMID: 7393270 DOI: 10.1056/nejm198008213030802] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The observation that high-dose oral vitamin E supplementation (800 IU per day) improved red-cell survival in two rare disorders associated with increased red-cell susceptibility to oxidative stress prompted a similar trial in 23 patients with Mediterranean glucose-6-phosphate dehydrogenase (G6PD) deficiency. Three months of vitamin E administration resulted in decreased chronic hemolysis as evidenced by improved red-cell life span (P less than 0.025), with an improvement in red-cell half-life from 22.9 +/- 0.7 days to 25.1 +/- 0.6 days (mean +/- S.E.M.), increased hemoglobin concentration (P less than 0.001), and decreased reticulocytosis (P less than 0.001) as compared with base-line values. Evaluation after one year of vitamin E administration demonstrated sustained improvement in all these indexes. Controlled clinical trials of vitamin E supplementation may be warranted to examine its efficacy in ameliorating acute hemolytic crises or in reducing morbidity from neonatal jaundice in this relatively common genetic disorder.
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