1
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Aureille J, Prabhu SS, Barnett SF, Farrugia AJ, Arnal I, Lafanechère L, Low BC, Kanchanawong P, Mogilner A, Bershadsky AD. Focal adhesions are controlled by microtubules through local contractility regulation. EMBO J 2024; 43:2715-2732. [PMID: 38769437 PMCID: PMC11217342 DOI: 10.1038/s44318-024-00114-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2023] [Revised: 04/12/2024] [Accepted: 04/15/2024] [Indexed: 05/22/2024] Open
Abstract
Microtubules regulate cell polarity and migration via local activation of focal adhesion turnover, but the mechanism of this process is insufficiently understood. Molecular complexes containing KANK family proteins connect microtubules with talin, the major component of focal adhesions. Here, local optogenetic activation of KANK1-mediated microtubule/talin linkage promoted microtubule targeting to an individual focal adhesion and subsequent withdrawal, resulting in focal adhesion centripetal sliding and rapid disassembly. This sliding is preceded by a local increase of traction force due to accumulation of myosin-II and actin in the proximity of the focal adhesion. Knockdown of the Rho activator GEF-H1 prevented development of traction force and abolished sliding and disassembly of focal adhesions upon KANK1 activation. Other players participating in microtubule-driven, KANK-dependent focal adhesion disassembly include kinases ROCK, PAK, and FAK, as well as microtubules/focal adhesion-associated proteins kinesin-1, APC, and αTAT. Based on these data, we develop a mathematical model for a microtubule-driven focal adhesion disruption involving local GEF-H1/RhoA/ROCK-dependent activation of contractility, which is consistent with experimental data.
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Affiliation(s)
- Julien Aureille
- Mechanobiology Institute, National University of Singapore, Singapore, Singapore.
| | - Srinivas S Prabhu
- Mechanobiology Institute, National University of Singapore, Singapore, Singapore
| | - Sam F Barnett
- Mechanobiology Institute, National University of Singapore, Singapore, Singapore
| | - Aaron J Farrugia
- Mechanobiology Institute, National University of Singapore, Singapore, Singapore
| | - Isabelle Arnal
- Grenoble institute of Neuroscience, University Grenoble Alpes, INSERM U1216, Grenoble, France
| | - Laurence Lafanechère
- University Grenoble Alpes, INSERM U1209, CNRS UMR5309, Institute for Advanced Biosciences, Grenoble, France
| | - Boon Chuan Low
- Mechanobiology Institute, National University of Singapore, Singapore, Singapore
| | - Pakorn Kanchanawong
- Mechanobiology Institute, National University of Singapore, Singapore, Singapore
- Department of Biomedical Engineering, National University of Singapore, Singapore, Singapore
| | - Alex Mogilner
- Courant Institute and Department of Biology, New York University, New York, USA
| | - Alexander D Bershadsky
- Mechanobiology Institute, National University of Singapore, Singapore, Singapore.
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel.
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2
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Virtanen V, Paunu K, Kukkula A, Niva S, Junila Y, Toriseva M, Jokilehto T, Mäkelä S, Huhtaniemi R, Poutanen M, Paatero I, Sundvall M. Glucocorticoid receptor-induced non-muscle caldesmon regulates metastasis in castration-resistant prostate cancer. Oncogenesis 2023; 12:42. [PMID: 37573448 PMCID: PMC10423232 DOI: 10.1038/s41389-023-00485-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 07/18/2023] [Accepted: 07/25/2023] [Indexed: 08/14/2023] Open
Abstract
Lethal prostate cancer (PCa) is characterized by the presence of metastases and development of resistance to therapies. Metastases form in a multi-step process enabled by dynamic cytoskeleton remodeling. An actin cytoskeleton regulating gene, CALD1, encodes a protein caldesmon (CaD). Its isoform, low-molecular-weight CaD (l-CaD), operates in non-muscle cells, supporting the function of filaments involved in force production and mechanosensing. Several factors, including glucocorticoid receptor (GR), have been identified as regulators of l-CaD in different cell types, but the regulation of l-CaD in PCa has not been defined. PCa develops resistance in response to therapeutic inhibition of androgen signaling by multiple strategies. Known strategies include androgen receptor (AR) alterations, modified steroid synthesis, and bypassing AR signaling, for example, by GR upregulation. Here, we report that in vitro downregulation of l-CaD promotes epithelial phenotype and reduces spheroid growth in 3D, which is reflected in vivo in reduced formation of metastases in zebrafish PCa xenografts. In accordance, CALD1 mRNA expression correlates with epithelial-to-mesenchymal transition (EMT) transcripts in PCa patients. We also show that CALD1 is highly co-expressed with GR in multiple PCa data sets, and GR activation upregulates l-CaD in vitro. Moreover, GR upregulation associates with increased l-CaD expression after the development of resistance to antiandrogen therapy in PCa xenograft mouse models. In summary, GR-regulated l-CaD plays a role in forming PCa metastases, being clinically relevant when antiandrogen resistance is attained by the means of bypassing AR signaling by GR upregulation.
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Affiliation(s)
- Verneri Virtanen
- Cancer Research Unit, Institute of Biomedicine, and FICAN West Cancer Center Laboratory, University of Turku, and Turku University Hospital, Kiinamyllynkatu 10, 20520, Turku, Finland
| | - Kreetta Paunu
- Cancer Research Unit, Institute of Biomedicine, and FICAN West Cancer Center Laboratory, University of Turku, and Turku University Hospital, Kiinamyllynkatu 10, 20520, Turku, Finland
| | - Antti Kukkula
- Cancer Research Unit, Institute of Biomedicine, and FICAN West Cancer Center Laboratory, University of Turku, and Turku University Hospital, Kiinamyllynkatu 10, 20520, Turku, Finland
| | - Saana Niva
- Cancer Research Unit, Institute of Biomedicine, and FICAN West Cancer Center Laboratory, University of Turku, and Turku University Hospital, Kiinamyllynkatu 10, 20520, Turku, Finland
| | - Ylva Junila
- Cancer Research Unit, Institute of Biomedicine, and FICAN West Cancer Center Laboratory, University of Turku, and Turku University Hospital, Kiinamyllynkatu 10, 20520, Turku, Finland
| | - Mervi Toriseva
- Cancer Research Unit, Institute of Biomedicine, and FICAN West Cancer Center Laboratory, University of Turku, and Turku University Hospital, Kiinamyllynkatu 10, 20520, Turku, Finland
| | - Terhi Jokilehto
- Cancer Research Unit, Institute of Biomedicine, and FICAN West Cancer Center Laboratory, University of Turku, and Turku University Hospital, Kiinamyllynkatu 10, 20520, Turku, Finland
| | - Sari Mäkelä
- Research Centre for Integrative Physiology and Pharmacology, Institute of Biomedicine, and FICAN West Cancer Center, University of Turku, Kiinamyllynkatu 10, 20520, Turku, Finland
| | - Riikka Huhtaniemi
- Research Centre for Integrative Physiology and Pharmacology, Institute of Biomedicine, and FICAN West Cancer Center, University of Turku, Kiinamyllynkatu 10, 20520, Turku, Finland
| | - Matti Poutanen
- Research Centre for Integrative Physiology and Pharmacology, Institute of Biomedicine, and FICAN West Cancer Center, University of Turku, Kiinamyllynkatu 10, 20520, Turku, Finland
| | - Ilkka Paatero
- Turku Bioscience Centre, University of Turku and Åbo Akademi University, Tykistökatu 6, 20520, Turku, Finland
| | - Maria Sundvall
- Cancer Research Unit, Institute of Biomedicine, and FICAN West Cancer Center Laboratory, University of Turku, and Turku University Hospital, Kiinamyllynkatu 10, 20520, Turku, Finland.
- Department of Oncology, Turku University Hospital, PL52, 20521, Turku, Finland.
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3
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Xie W, Wei X, Kang H, Jiang H, Chu Z, Lin Y, Hou Y, Wei Q. Static and Dynamic: Evolving Biomaterial Mechanical Properties to Control Cellular Mechanotransduction. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2204594. [PMID: 36658771 PMCID: PMC10037983 DOI: 10.1002/advs.202204594] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 12/28/2022] [Indexed: 06/17/2023]
Abstract
The extracellular matrix (ECM) is a highly dynamic system that constantly offers physical, biological, and chemical signals to embraced cells. Increasing evidence suggests that mechanical signals derived from the dynamic cellular microenvironment are essential controllers of cell behaviors. Conventional cell culture biomaterials, with static mechanical properties such as chemistry, topography, and stiffness, have offered a fundamental understanding of various vital biochemical and biophysical processes, such as cell adhesion, spreading, migration, growth, and differentiation. At present, novel biomaterials that can spatiotemporally impart biophysical cues to manipulate cell fate are emerging. The dynamic properties and adaptive traits of new materials endow them with the ability to adapt to cell requirements and enhance cell functions. In this review, an introductory overview of the key players essential to mechanobiology is provided. A biophysical perspective on the state-of-the-art manipulation techniques and novel materials in designing static and dynamic ECM-mimicking biomaterials is taken. In particular, different static and dynamic mechanical cues in regulating cellular mechanosensing and functions are compared. This review to benefit the development of engineering biomechanical systems regulating cell functions is expected.
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Affiliation(s)
- Wenyan Xie
- Department of BiotherapyState Key Laboratory of Biotherapy and Cancer CenterWest China HospitalSichuan UniversityChengduSichuan610065China
| | - Xi Wei
- Department of Mechanical EngineeringThe University of Hong KongHong KongChina
| | - Heemin Kang
- Department of Materials Science and EngineeringKorea UniversitySeoul02841South Korea
| | - Hong Jiang
- Department of BiotherapyState Key Laboratory of Biotherapy and Cancer CenterWest China HospitalSichuan UniversityChengduSichuan610065China
| | - Zhiqin Chu
- Department of Electrical and Electronic Engineering (Joint Appointment with School of Biomedical Sciences)The University of Hong KongHong KongChina
| | - Yuan Lin
- Department of Mechanical EngineeringThe University of Hong KongHong KongChina
| | - Yong Hou
- Department of Electrical and Electronic EngineeringThe University of Hong KongHong KongChina
- Institut für Chemie und BiochemieFreie Universität BerlinTakustrasse 314195BerlinGermany
| | - Qiang Wei
- College of Polymer Science and EngineeringState Key Laboratory of Polymer Materials and EngineeringSichuan UniversityChengdu610065China
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4
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Paltsev MA, Markelova AY, Mironova ES, Novak-Bobarykina UA, Zubareva TS, Khop DN, Kvetnoy IM. [Caldesmon and tumor growth: prospects for optimizing diagnosis and targeted therapy]. Arkh Patol 2023; 85:53-59. [PMID: 37053355 DOI: 10.17116/patol20238502153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/15/2023]
Abstract
Tumor invasion plays a key role in the progression of tumors. This process is regulated by the interactions of cells and tissues, in which physical, cellular and molecular determinants undergo changes throughout the entire period of progression of tumor growth. Tumor invasion is triggered and maintained by specialized signal cascades that control the dynamic state of the cytoskeleton in tumor cells, the processes of rearrangement of cell-matrix and intercellular connections, followed by cell migration to neighboring tissues. Studying the mechanisms of regulation of cell motor activity and determining its main regulators is an important task for understanding the pathophysiology of tumor growth. Caldesmon is an actin, myosin and calmodulin binding protein. It is involved in the regulation of smooth muscle contraction by inhibiting actin and myosin binding, in the formation of actin stress fibers, and in the transport of intracellular granules. Currently, caldesmon is considered as a potential biomarker of tumor cell invasion, migration, and metastasis. The study of signaling molecules involved in tumor progression, such as caldesmon, is necessary to predict response to chemotherapy and radiotherapy. This review highlights the main functions of caldesmon and analyzes its role in oncological pathology.
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Affiliation(s)
- M A Paltsev
- Lomonosov Moscow State University, Moscow, Russia
| | - A Yu Markelova
- Peter the Great St. Petersburg Polytechnic University, St. Petersburg, Russia
| | - E S Mironova
- St. Petersburg Research Institute of Phthisiopulmonology, St. Petersburg, Russia
- St. Petersburg Institute of Bioregulation and Gerontology, St. Petersburg, Russia
| | | | - T S Zubareva
- St. Petersburg Research Institute of Phthisiopulmonology, St. Petersburg, Russia
- St. Petersburg Institute of Bioregulation and Gerontology, St. Petersburg, Russia
| | - D N Khop
- St. Petersburg State University, St. Petersburg, Russia
- Vietnam Military Medical University, Hanoi, Vietnam
| | - I M Kvetnoy
- St. Petersburg Research Institute of Phthisiopulmonology, St. Petersburg, Russia
- St. Petersburg State University, St. Petersburg, Russia
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5
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Kokate SB, Ciuba K, Tran VD, Kumari R, Tojkander S, Engel U, Kogan K, Kumar S, Lappalainen P. Caldesmon controls stress fiber force-balance through dynamic cross-linking of myosin II and actin-tropomyosin filaments. Nat Commun 2022; 13:6032. [PMID: 36229430 PMCID: PMC9561149 DOI: 10.1038/s41467-022-33688-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 09/28/2022] [Indexed: 11/09/2022] Open
Abstract
Contractile actomyosin bundles are key force-producing and mechanosensing elements in muscle and non-muscle tissues. Whereas the organization of muscle myofibrils and mechanism regulating their contractility are relatively well-established, the principles by which myosin-II activity and force-balance are regulated in non-muscle cells have remained elusive. We show that Caldesmon, an important component of smooth muscle and non-muscle cell actomyosin bundles, is an elongated protein that functions as a dynamic cross-linker between myosin-II and tropomyosin-actin filaments. Depletion of Caldesmon results in aberrant lateral movement of myosin-II filaments along actin bundles, leading to irregular myosin distribution within stress fibers. This manifests as defects in stress fiber network organization and contractility, and accompanied problems in cell morphogenesis, migration, invasion, and mechanosensing. These results identify Caldesmon as critical factor that ensures regular myosin-II spacing within non-muscle cell actomyosin bundles, and reveal how stress fiber networks are controlled through dynamic cross-linking of tropomyosin-actin and myosin filaments.
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Affiliation(s)
- Shrikant B Kokate
- HiLIFE Institute of Biotechnology, University of Helsinki, P.O. Box 56, 00014, Helsinki, Finland
| | - Katarzyna Ciuba
- HiLIFE Institute of Biotechnology, University of Helsinki, P.O. Box 56, 00014, Helsinki, Finland.,Nencki Institute of Experimental Biology PAS, 3 Pasteur Street, 02-093, Warszawa, Poland
| | - Vivien D Tran
- Department of Bioengineering, University of California, Berkeley, CA, 94720, USA
| | - Reena Kumari
- HiLIFE Institute of Biotechnology, University of Helsinki, P.O. Box 56, 00014, Helsinki, Finland
| | - Sari Tojkander
- Faculty of Medicine and Health Technology, Tampere University, Kauppi Campus, Arvo Building, E318, Arvo Ylpön katu 34, 33520, Tampere, Finland
| | - Ulrike Engel
- Nikon Imaging Center at Heidelberg University and Centre for Organismal Studies (COS), Heidelberg University, Im Neuenheimer Feld 267, Heidelberg, 69120, Germany
| | - Konstantin Kogan
- HiLIFE Institute of Biotechnology, University of Helsinki, P.O. Box 56, 00014, Helsinki, Finland
| | - Sanjay Kumar
- Department of Bioengineering, University of California, Berkeley, CA, 94720, USA
| | - Pekka Lappalainen
- HiLIFE Institute of Biotechnology, University of Helsinki, P.O. Box 56, 00014, Helsinki, Finland.
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6
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Alnuaimi AR, Nair VA, Malhab LJB, Abu-Gharbieh E, Ranade AV, Pintus G, Hamad M, Busch H, Kirfel J, Hamoudi R, Abdel-Rahman WM. Emerging role of caldesmon in cancer: A potential biomarker for colorectal cancer and other cancers. World J Gastrointest Oncol 2022; 14:1637-1653. [PMID: 36187394 PMCID: PMC9516648 DOI: 10.4251/wjgo.v14.i9.1637] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 05/05/2022] [Accepted: 07/26/2022] [Indexed: 02/05/2023] Open
Abstract
Colorectal cancer (CRC) is a devastating disease, mainly because of metastasis. As a result, there is a need to better understand the molecular basis of invasion and metastasis and to identify new biomarkers and therapeutic targets to aid in managing these tumors. The actin cytoskeleton and actin-binding proteins are known to play an important role in the process of cancer metastasis because they control and execute essential steps in cell motility and contractility as well as cell division. Caldesmon (CaD) is an actin-binding protein encoded by the CALD1 gene as multiple transcripts that mainly encode two protein isoforms: High-molecular-weight CaD, expressed in smooth muscle, and low-molecular weight CaD (l-CaD), expressed in nonsmooth muscle cells. According to our comprehensive review of the literature, CaD, particularly l-CaD, plays a key role in the development, metastasis, and resistance to chemoradiotherapy in colorectal, breast, and urinary bladder cancers and gliomas, among other malignancies. CaD is involved in many aspects of the carcinogenic hallmarks, including epithelial mesenchymal transition via transforming growth factor-beta signaling, angiogenesis, resistance to hormonal therapy, and immune evasion. Recent data show that CaD is expressed in tumor cells as well as in stromal cells, such as cancer-associated fibroblasts, where it modulates the tumor microenvironment to favor the tumor. Interestingly, CaD undergoes selective tumor-specific splicing, and the resulting isoforms are generally not expressed in normal tissues, making these transcripts ideal targets for drug design. In this review, we will analyze these features of CaD with a focus on CRC and show how the currently available data qualify CaD as a potential candidate for targeted therapy in addition to its role in the diagnosis and prognosis of cancer.
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Affiliation(s)
- Alya R Alnuaimi
- Sharjah Institute for Medical Research, University of Sharjah, Sharjah 27272, United Arab Emirates
- College of Medicine, University of Sharjah, Sharjah 27272, United Arab Emirates
| | - Vidhya A Nair
- Sharjah Institute for Medical Research, University of Sharjah, Sharjah 27272, United Arab Emirates
| | - Lara J Bou Malhab
- Sharjah Institute for Medical Research, University of Sharjah, Sharjah 27272, United Arab Emirates
| | - Eman Abu-Gharbieh
- Sharjah Institute for Medical Research, University of Sharjah, Sharjah 27272, United Arab Emirates
- Department of Clinical Sciences, University of Sharjah, Sharjah 27272, United Arab Emirates
| | - Anu Vinod Ranade
- Sharjah Institute for Medical Research, University of Sharjah, Sharjah 27272, United Arab Emirates
- Department of Basic Medical Sciences, University of Sharjah, Sharjah 27272, United Arab Emirates
| | - Gianfranco Pintus
- Sharjah Institute for Medical Research, University of Sharjah, Sharjah 27272, United Arab Emirates
- Department of Medical Laboratory Sciences, University of Sharjah, Sharjah 27272, United Arab Emirates
- Department of Biomedical Sciences, University of Sassari, Sassari 07100, Italy
| | - Mohamad Hamad
- Sharjah Institute for Medical Research, University of Sharjah, Sharjah 27272, United Arab Emirates
- Department of Medical Laboratory Sciences, University of Sharjah, Sharjah 27272, United Arab Emirates
| | - Hauke Busch
- University Cancer Center Schleswig-Holstein and Luebeck Institute for Experimental Dermatology, University of Luebeck, Luebeck 23560, Germany
| | - Jutta Kirfel
- Institute of Pathology, University Hospital Schleswig-Holstein, Luebeck 23560, Germany
| | - Rifat Hamoudi
- Sharjah Institute for Medical Research, University of Sharjah, Sharjah 27272, United Arab Emirates
- Department of Clinical Sciences, University of Sharjah, Sharjah 27272, United Arab Emirates
- Division of Surgery and Interventional Science, University College London, London WC1E 6BT, United Kingdom
| | - Wael M Abdel-Rahman
- Sharjah Institute for Medical Research, University of Sharjah, Sharjah 27272, United Arab Emirates
- Department of Medical Laboratory Sciences, University of Sharjah, Sharjah 27272, United Arab Emirates
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7
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Chandurkar MK, Han SJ. Subcellular Force Quantification of Endothelial Cells Using Silicone Pillar Arrays. Methods Mol Biol 2022; 2375:229-245. [PMID: 34591312 PMCID: PMC11139549 DOI: 10.1007/978-1-0716-1708-3_19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Micropillar arrays are one of the tools that quantify the mechanical forces exerted by endothelial cells and any other adherent cell types. This chapter describes the fabrication and usage of the micropillars that reports spatial distribution of traction forces by endothelial cells. The fabrication begins with making a "master" pillar substrate using photolithography, followed by softlithography of the master with polydimethylsiloxane. The pillars can then be printed with an extracellular matrix protein in specific shape using stamp-off technique. Lastly, imaging of the micropillars with cells and the analysis of the traction force using Matlab-based software are described.
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Affiliation(s)
- Mohanish K Chandurkar
- Department of Biomedical Engineering, Michigan Technological University, Houghton, MI, USA
| | - Sangyoon J Han
- Department of Biomedical Engineering, Michigan Technological University, Houghton, MI, USA.
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8
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Li C, Yang F, Wang R, Li W, Maskey N, Zhang W, Guo Y, Liu S, Wang H, Yao X. CALD1 promotes the expression of PD-L1 in bladder cancer via the JAK/STAT signaling pathway. ANNALS OF TRANSLATIONAL MEDICINE 2021; 9:1441. [PMID: 34733993 PMCID: PMC8506703 DOI: 10.21037/atm-21-4192] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Accepted: 09/02/2021] [Indexed: 02/05/2023]
Abstract
Background Bladder cancer (BC) is a common malignant neoplasm with a high rate of recurrence and progression, despite optimal treatment. There is a pressing need to identify new effective biomarkers for the targeted treatment of BC. Methods The key gene CALD1 was screened via weighed gene co-expression network analysis (WGCNA) from encoding protein genes of BC. Clinical and prognostic significance was explored in The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Cell Counting Kit-8 (CCK-8), flow cytometry, transwell chamber experiment and nude mouse xenograft assay were performed to test cell growth, apoptosis, migration, invasion and tumorigenesis capacities. Immune correlation was analyzed in The Tumor Immune Estimation Resource (TIMER) database. Relevant signaling pathways were explored using gene set enrichment analysis (GSEA). Results Increased expression of CALD1 was significantly correlated with histological grade, clinical stage, T stage, and lymphatic metastasis. Kaplan-Meier survival curves showed that high CALD1 expression was associated with poor overall survival (OS) and disease-free survival (DFS) in TCGA database, and with poor OS in the four GEO databases. CALD1 promotes growth, migration, invasion, and cell cycle of tumor cell, and inhibits tumor cell apoptosis in vitro and in vivo. CADL1 expression was positively correlated with increased CD274 levels (r=0.357, P=9.71e−14). JAK/STAT signaling pathway was significantly enriched in the high CALD1 expression group. CALD1-mediated PD-L1 overexpression (OE) was via the activation of the JAK/STAT signaling pathway; this effect was blocked by the specific JAK inhibitor Ruxolitinib. Conclusions CALD1 is a potential molecular marker associated with prognosis. It promotes the malignant progression of BC and upregulates the PD-L1 expression via the JAK/STAT signaling pathway.
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Affiliation(s)
- Cheng Li
- Department of Urology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China.,Urologic Cancer Institute, Tongji University School of Medicine, Shanghai, China
| | - Fuhan Yang
- Department of Urology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China.,Urologic Cancer Institute, Tongji University School of Medicine, Shanghai, China
| | - Ruiliang Wang
- Department of Urology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China.,Urologic Cancer Institute, Tongji University School of Medicine, Shanghai, China
| | - Wei Li
- Department of Urology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China.,Urologic Cancer Institute, Tongji University School of Medicine, Shanghai, China
| | - Niraj Maskey
- Department of Urology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China.,Urologic Cancer Institute, Tongji University School of Medicine, Shanghai, China
| | - Wentao Zhang
- Department of Urology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China.,Urologic Cancer Institute, Tongji University School of Medicine, Shanghai, China
| | - Yadong Guo
- Department of Urology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China.,Urologic Cancer Institute, Tongji University School of Medicine, Shanghai, China
| | - Shenghua Liu
- Department of Urology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China.,Urologic Cancer Institute, Tongji University School of Medicine, Shanghai, China
| | - Hong Wang
- Department of Urology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China.,Urologic Cancer Institute, Tongji University School of Medicine, Shanghai, China
| | - Xudong Yao
- Department of Urology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China.,Urologic Cancer Institute, Tongji University School of Medicine, Shanghai, China
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9
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Obenaus AM, Mollica MY, Sniadecki NJ. (De)form and Function: Measuring Cellular Forces with Deformable Materials and Deformable Structures. Adv Healthc Mater 2020; 9:e1901454. [PMID: 31951099 PMCID: PMC7274881 DOI: 10.1002/adhm.201901454] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 12/04/2019] [Indexed: 12/29/2022]
Abstract
The ability for biological cells to produce mechanical forces is important for the development, function, and homeostasis of tissue. The measurement of cellular forces is not a straightforward task because individual cells are microscopic in size and the forces they produce are at the nanonewton scale. Consequently, studies in cell mechanics rely on advanced biomaterials or flexible structures that permit one to infer these forces by the deformation they impart on the material or structure. Herein, the scientific progression on the use of deformable materials and deformable structures to measure cellular forces are reviewed. The findings and insights made possible with these approaches in the field of cell mechanics are summarized.
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Affiliation(s)
- Ava M Obenaus
- Department of Mechanical Engineering, University of Washington, Seattle, WA, 98195, USA
| | - Molly Y Mollica
- Department of Bioengineering, University of Washington, Seattle, WA, 98195, USA
| | - Nathan J Sniadecki
- Department of Mechanical Engineering, University of Washington, Seattle, WA, 98195, USA
- Department of Bioengineering, University of Washington, Seattle, WA, 98195, USA
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA, 98195, USA
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10
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Nalluri SM, O'Connor JW, Virgi GA, Stewart SE, Ye D, Gomez EW. TGFβ1-induced expression of caldesmon mediates epithelial-mesenchymal transition. Cytoskeleton (Hoboken) 2018; 75:201-212. [PMID: 29466836 DOI: 10.1002/cm.21437] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 02/13/2018] [Accepted: 02/19/2018] [Indexed: 12/15/2022]
Abstract
Epithelial-mesenchymal transition (EMT) is an important process that mediates organ development and wound healing, and in pathological contexts, it can contribute to the progression of fibrosis and cancer. During EMT, cells exhibit marked changes in cytoskeletal organization and increased expression of a variety of actin associated proteins. Here, we sought to determine the role of caldesmon in mediating EMT in response to transforming growth factor (TGF)-β1. We find that the expression level and phosphorylation state of caldesmon increase as a function of time following induction of EMT by TGFβ1 and these changes in caldesmon correlate with increased focal adhesion number and size and increased cell contractility. Knockdown and forced expression of caldesmon in epithelial cells reveals that caldesmon expression plays an important role in regulating the expression of the myofibroblast marker alpha smooth muscle actin. Results from these studies provide insight into the role of cytoskeletal associated proteins in the regulation of EMT and may suggest ways to target the cell cytoskeleton for regulating EMT processes.
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Affiliation(s)
- Sandeep M Nalluri
- Department of Chemical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - Joseph W O'Connor
- Department of Chemical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - Gage A Virgi
- Department of Chemical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - Samantha E Stewart
- Department of Biomedical Engineering, University of South Carolina, Columbia, South Carolina 29208
| | - Dan Ye
- Department of Chemical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - Esther W Gomez
- Department of Chemical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802.,Department of Biomedical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802
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11
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Wouters OY, Ploeger DTA, van Putten SM, Bank RA. 3,4-Dihydroxy-L-Phenylalanine as a Novel Covalent Linker of Extracellular Matrix Proteins to Polyacrylamide Hydrogels with a Tunable Stiffness. Tissue Eng Part C Methods 2016; 22:91-101. [PMID: 26779898 DOI: 10.1089/ten.tec.2015.0312] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Cells acquire mechanical information from their surrounding and convert this into biochemical activity. The concept and mechanism behind this cellular mechanosensing and mechanotransduction are often studied by means of two-dimensional hydrogels. Polyacrylamide hydrogels (PAAMs) offer chemical, mechanical, and optical advantages but due to their inert surface do not allow protein and cell adherence. Several cross-linkers have been used to functionalize the surface of PAAMs with extracellular matrix (ECM) proteins to enable cell culture. However, the most commonly used cross-linkers are either unstable, expensive, or laborious and often show heterogeneous coating or require PAAM modification. Here, we introduce 3,4-dihydroxy-l-phenylalanine (L-DOPA) as a novel cross-linker that can functionalize PAAMs with ECM without the above-mentioned disadvantages. A homogenous collagen type I and fibronectin coating was observed after L-DOPA functionalization. Fibroblasts responded to differences in PAAMs' stiffness; morphology, cell area, and protein localization were all affected as expected, in accordance with literature where other cross-linkers were used. In conclusion, L-DOPA can be used as a cross-linker between PAAMs and ECM and represents a novel, straightforward, nonlaborious, and robust method to functionalize PAAMs for cell culture to study cell mechanosensing.
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Affiliation(s)
- Olaf Y Wouters
- 1 Department of Pathology and Medical Biology, University of Groningen, University Medical Center Groningen , Groningen, The Netherlands
| | - Diana T A Ploeger
- 1 Department of Pathology and Medical Biology, University of Groningen, University Medical Center Groningen , Groningen, The Netherlands
| | - Sander M van Putten
- 1 Department of Pathology and Medical Biology, University of Groningen, University Medical Center Groningen , Groningen, The Netherlands .,2 Synvolux Therapeutics , Groningen, The Netherlands
| | - Ruud A Bank
- 1 Department of Pathology and Medical Biology, University of Groningen, University Medical Center Groningen , Groningen, The Netherlands
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12
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Nalluri SM, O'Connor JW, Gomez EW. Cytoskeletal signaling in TGFβ-induced epithelial-mesenchymal transition. Cytoskeleton (Hoboken) 2015; 72:557-69. [PMID: 26543012 DOI: 10.1002/cm.21263] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Revised: 11/04/2015] [Accepted: 11/04/2015] [Indexed: 12/13/2022]
Abstract
Epithelial-mesenchymal transition (EMT) is a physiological process that plays an important role in embryonic development and wound healing and is appropriated during pathological conditions including fibrosis and cancer metastasis. EMT can be initiated by a variety of factors, including transforming growth factor (TGF)-β, and is characterized by loss of epithelial features including cell-cell contacts and apicobasal polarity and acquisition of a motile, mesenchymal phenotype. A key feature of EMT is reorganization of the cytoskeleton and recent studies have elucidated regulation mechanisms governing this process. This review describes changes in gene expression patterns of cytoskeletal associated proteins during TGFβ-induced EMT. It further reports TGFβ-induced intracellular signaling cascades that regulate cytoskeletal reorganization during EMT. Finally, it highlights how changes in cytoskeletal architecture during EMT can regulate gene expression, thus further promoting EMT progression.
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Affiliation(s)
- Sandeep M Nalluri
- Department of Chemical Engineering, The Pennsylvania State University, University Park, Pennsylvania, 16802
| | - Joseph W O'Connor
- Department of Chemical Engineering, The Pennsylvania State University, University Park, Pennsylvania, 16802
| | - Esther W Gomez
- Department of Chemical Engineering, The Pennsylvania State University, University Park, Pennsylvania, 16802.,Department of Biomedical Engineering, The Pennsylvania State University, University Park, Pennsylvania, 16802
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13
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Permyakov SE, Permyakov EA, Uversky VN. Intrinsically disordered caldesmon binds calmodulin via the "buttons on a string" mechanism. PeerJ 2015; 3:e1265. [PMID: 26417545 PMCID: PMC4582948 DOI: 10.7717/peerj.1265] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Accepted: 09/03/2015] [Indexed: 01/27/2023] Open
Abstract
We show here that chicken gizzard caldesmon (CaD) and its C-terminal domain (residues 636–771, CaD136) are intrinsically disordered proteins. The computational and experimental analyses of the wild type CaD136 and series of its single tryptophan mutants (W674A, W707A, and W737A) and a double tryptophan mutant (W674A/W707A) suggested that although the interaction of CaD136 with calmodulin (CaM) can be driven by the non-specific electrostatic attraction between these oppositely charged molecules, the specificity of CaD136-CaM binding is likely to be determined by the specific packing of important CaD136 tryptophan residues at the CaD136-CaM interface. It is suggested that this interaction can be described as the “buttons on a charged string” model, where the electrostatic attraction between the intrinsically disordered CaD136 and the CaM is solidified in a “snapping buttons” manner by specific packing of the CaD136 “pliable buttons” (which are the short segments of fluctuating local structure condensed around the tryptophan residues) at the CaD136-CaM interface. Our data also show that all three “buttons” are important for binding, since mutation of any of the tryptophans affects CaD136-CaM binding and since CaD136 remains CaM-buttoned even when two of the three tryptophans are mutated to alanines.
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Affiliation(s)
- Sergei E Permyakov
- Protein Research Group, Institute for Biological Instrumentation, Russian Academy of Sciences , Pushchino, Moscow Region , Russia
| | - Eugene A Permyakov
- Protein Research Group, Institute for Biological Instrumentation, Russian Academy of Sciences , Pushchino, Moscow Region , Russia
| | - Vladimir N Uversky
- Protein Research Group, Institute for Biological Instrumentation, Russian Academy of Sciences , Pushchino, Moscow Region , Russia ; Department of Molecular Medicine, University of South Florida , Tampa, FL , USA
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14
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Micro- and nanodevices integrated with biomolecular probes. Biotechnol Adv 2015; 33:1727-43. [PMID: 26363089 PMCID: PMC4948648 DOI: 10.1016/j.biotechadv.2015.09.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Revised: 08/06/2015] [Accepted: 09/05/2015] [Indexed: 12/28/2022]
Abstract
Understanding how biomolecules, proteins and cells interact with their surroundings and other biological entities has become the fundamental design criterion for most biomedical micro- and nanodevices. Advances in biology, medicine, and nanofabrication technologies complement each other and allow us to engineer new tools based on biomolecules utilized as probes. Engineered micro/nanosystems and biomolecules in nature have remarkably robust compatibility in terms of function, size, and physical properties. This article presents the state of the art in micro- and nanoscale devices designed and fabricated with biomolecular probes as their vital constituents. General design and fabrication concepts are presented and three major platform technologies are highlighted: microcantilevers, micro/nanopillars, and microfluidics. Overview of each technology, typical fabrication details, and application areas are presented by emphasizing significant achievements, current challenges, and future opportunities.
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15
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Integration of actin dynamics and cell adhesion by a three-dimensional, mechanosensitive molecular clutch. Nat Cell Biol 2015; 17:955-63. [PMID: 26121555 DOI: 10.1038/ncb3191] [Citation(s) in RCA: 330] [Impact Index Per Article: 36.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Accepted: 05/15/2015] [Indexed: 12/12/2022]
Abstract
During cell migration, the forces generated in the actin cytoskeleton are transmitted across transmembrane receptors to the extracellular matrix or other cells through a series of mechanosensitive, regulable protein-protein interactions termed the molecular clutch. In integrin-based focal adhesions, the proteins forming this linkage are organized into a conserved three-dimensional nano-architecture. Here we discuss how the physical interactions between the actin cytoskeleton and focal-adhesion-associated molecules mediate force transmission from the molecular clutch to the extracellular matrix.
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16
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Sun J, Xiao Y, Wang S, Slepian MJ, Wong PK. Advances in Techniques for Probing Mechanoregulation of Tissue Morphogenesis. ACTA ACUST UNITED AC 2015; 20:127-37. [DOI: 10.1177/2211068214554802] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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17
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Haase K, Pelling AE. Investigating cell mechanics with atomic force microscopy. J R Soc Interface 2015; 12:20140970. [PMID: 25589563 PMCID: PMC4345470 DOI: 10.1098/rsif.2014.0970] [Citation(s) in RCA: 216] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Accepted: 12/18/2014] [Indexed: 12/12/2022] Open
Abstract
Transmission of mechanical force is crucial for normal cell development and functioning. However, the process of mechanotransduction cannot be studied in isolation from cell mechanics. Thus, in order to understand how cells 'feel', we must first understand how they deform and recover from physical perturbations. Owing to its versatility, atomic force microscopy (AFM) has become a popular tool to study intrinsic cellular mechanical properties. Used to directly manipulate and examine whole and subcellular reactions, AFM allows for top-down and reconstitutive approaches to mechanical characterization. These studies show that the responses of cells and their components are complex, and largely depend on the magnitude and time scale of loading. In this review, we generally describe the mechanotransductive process through discussion of well-known mechanosensors. We then focus on discussion of recent examples where AFM is used to specifically probe the elastic and inelastic responses of single cells undergoing deformation. We present a brief overview of classical and current models often used to characterize observed cellular phenomena in response to force. Both simple mechanistic models and complex nonlinear models have been used to describe the observed cellular behaviours, however a unifying description of cell mechanics has not yet been resolved.
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Affiliation(s)
- Kristina Haase
- Department of Physics, Centre for Interdisciplinary NanoPhysics, MacDonald Hall, University of Ottawa, 150 Louis Pasteur, Ottawa, Ontario, Canada
| | - Andrew E Pelling
- Department of Physics, Centre for Interdisciplinary NanoPhysics, MacDonald Hall, University of Ottawa, 150 Louis Pasteur, Ottawa, Ontario, Canada Department of Biology, Gendron Hall, 30 Marie Curie, University of Ottawa, Ottawa, Ontario, Canada Institute for Science Society and Policy, Desmarais Building, 55 Laurier Ave. East, University of Ottawa, Ottawa, Ontario, Canada K1N 6N5
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18
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Yu HW, Chen YQ, Huang CM, Liu CY, Chiou A, Wang YK, Tang MJ, Kuo JC. β-PIX controls intracellular viscoelasticity to regulate lung cancer cell migration. J Cell Mol Med 2015; 19:934-47. [PMID: 25683605 PMCID: PMC4420597 DOI: 10.1111/jcmm.12441] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Accepted: 08/22/2014] [Indexed: 01/08/2023] Open
Abstract
Cancer metastasis occurs via a progress involving abnormal cell migration. Cell migration, a dynamic physical process, is controlled by the cytoskeletal system, which includes the dynamics of actin organization and cellular adhesive organelles, focal adhesions (FAs). However, it is not known whether the organization of actin cytoskeletal system has a regulatory role in the physiologically relevant aspects of cancer metastasis. In the present studies, it was found that lung adenocarcinoma cells isolated from the secondary lung cancer of the lymph nodes, H1299 cells, show specific dynamics in terms of the actin cytoskeleton and FAs. This results in a higher level of mobility and this is regulated by an immature FA component, β-PIX (PAK-interacting exchange factor-β). In H1299 cells, β-PIX's activity was found not to be down-regulated by sequestration onto stress fibres, as the cells did not bundle actin filaments into stress fibres. Thus, β-PIX mainly remained localized at FAs, which allowed maturation of nascent adhesions into focal complexes; this resulted in actin polymerization, increased actin network integrity, changes in the intracellular microrheology at the peripheral of the cell, and cell polarity, which in turn regulated cell migration. Perturbation of β-PIX caused an inhibition of cell migration, including migration velocity, accumulated distance and directional persistence. Our results demonstrate the importance of β-PIX to the regulation of high mobility of lung adenocarcinoma cell line H1299 and that this occurs via regulation of FA dynamics, changes in actin cytoskeleton organization and cell polarity.
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Affiliation(s)
- Helen Wenshin Yu
- Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan
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19
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Sekar MC, Shahiwala K, Leloup L, Wells A. Modulation of Epidermal Growth Factor Stimulated ERK Phosphorylation and Cell Motility by Inositol Trisphosphate Kinase. ACTA ACUST UNITED AC 2014. [PMID: 26213696 DOI: 10.1166/jpsp.2014.1010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Epidermal growth factor [EGF] mediated stimulation of its receptor in endothelial cell [EC] is accompanied by phosphorylation of the EGF-receptor [EGFR] and activation of phospholipase C-γ, resulting in the breakdown of phosphatidylinositol(4,5)-bisphosphate and generating inositol (1,4,5)-trisphosphate [IP3] and diacylglycerol. IP3 thus formed can be further converted to inositol (1,3,4,5)-tetrakisphosphate [IP4] by an enzyme called IP3-kinase [IP3K]. In this study we have investigated the effect of modulation of intracellular IP3K activity by the use of an inhibitor, 2-trifluoromethyl [6-(4-nitrobenzyl)-purine] [IP3KI] and siRNA against IP3KB on EGF-induced ERK-phosphorylation and cell motility. EGF stimulated ERK-phosphorylation that has been implicated in EGF-stimulated cell migration was inhibited by both IP3KI and siRNA against IP3KB. Inhibition of ERK-phosphorylation was accompanied by decreased cell migration in the presence of IP3KI.
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Affiliation(s)
- M C Sekar
- College of Pharmacy, University of Findlay, Findlay, 45840, OH, USA
| | - K Shahiwala
- College of Pharmacy, University of Findlay, Findlay, 45840, OH, USA
| | - L Leloup
- Department of Pathology, University of Pittsburgh, Pittsburgh, 15261, PA, USA
| | - A Wells
- Department of Pathology, University of Pittsburgh, Pittsburgh, 15261, PA, USA
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20
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Unal M, Alapan Y, Jia H, Varga AG, Angelino K, Aslan M, Sayin I, Han C, Jiang Y, Zhang Z, Gurkan UA. Micro and Nano-Scale Technologies for Cell Mechanics. Nanobiomedicine (Rij) 2014; 1:5. [PMID: 30023016 PMCID: PMC6029242 DOI: 10.5772/59379] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Accepted: 09/18/2014] [Indexed: 01/09/2023] Open
Abstract
Cell mechanics is a multidisciplinary field that bridges cell biology, fundamental mechanics, and micro and nanotechnology, which synergize to help us better understand the intricacies and the complex nature of cells in their native environment. With recent advances in nanotechnology, microfabrication methods and micro-electro-mechanical-systems (MEMS), we are now well situated to tap into the complex micro world of cells. The field that brings biology and MEMS together is known as Biological MEMS (BioMEMS). BioMEMS take advantage of systematic design and fabrication methods to create platforms that allow us to study cells like never before. These new technologies have been rapidly advancing the study of cell mechanics. This review article provides a succinct overview of cell mechanics and comprehensively surveys micro and nano-scale technologies that have been specifically developed for and are relevant to the mechanics of cells. Here we focus on micro and nano-scale technologies, and their applications in biology and medicine, including imaging, single cell analysis, cancer cell mechanics, organ-on-a-chip systems, pathogen detection, implantable devices, neuroscience and neurophysiology. We also provide a perspective on the future directions and challenges of technologies that relate to the mechanics of cells.
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Affiliation(s)
- Mustafa Unal
- Department of Electrical Engineering and Computer Science, Case Western Reserve University, Cleveland, USA
| | - Yunus Alapan
- Department of Electrical Engineering and Computer Science, Case Western Reserve University, Cleveland, USA
- Case Biomanufacturing and Microfabrication Laboratory, Case Western Reserve University, Cleveland, USA
| | - Hao Jia
- Department of Biology, Case Western Reserve University, Cleveland, USA
| | - Adrienn G. Varga
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, USA
| | - Keith Angelino
- Department of Civil Engineering, Case Western Reserve University, Cleveland, USA
| | - Mahmut Aslan
- Department of Electrical Engineering and Computer Science, Case Western Reserve University, Cleveland, USA
- Case Biomanufacturing and Microfabrication Laboratory, Case Western Reserve University, Cleveland, USA
| | - Ismail Sayin
- Case Biomanufacturing and Microfabrication Laboratory, Case Western Reserve University, Cleveland, USA
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, USA
| | - Chanjuan Han
- Department of Mechanical and Aerospace Engineering, Case Western Reserve University, Cleveland, USA
| | - Yanxia Jiang
- Department of Electrical Engineering and Computer Science, Case Western Reserve University, Cleveland, USA
| | - Zhehao Zhang
- Department of Civil Engineering, Case Western Reserve University, Cleveland, USA
| | - Umut A. Gurkan
- Department of Electrical Engineering and Computer Science, Case Western Reserve University, Cleveland, USA
- Case Biomanufacturing and Microfabrication Laboratory, Case Western Reserve University, Cleveland, USA
- Department of Orthopaedics, Case Western Reserve University, Cleveland, USA
- Advanced Platform Technology Center, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, USA
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21
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Kuo JC. Focal adhesions function as a mechanosensor. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2014; 126:55-73. [PMID: 25081614 DOI: 10.1016/b978-0-12-394624-9.00003-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Focal adhesions (FAs) are complex plasma membrane-associated macromolecular assemblies that engage with the surrounding extracellular matrix (ECM) via integrin receptors and physically connect with the actin cytoskeleton through the recruitment of numerous FA-associated proteins. FAs undergo a maturation process, which is known to be induced by biochemical or physical cues, to grow and change composition. Varying FA size, distribution, dynamics, and compositions during maturation process is required for transducing the specific signaling networks that reflect the requirements of a cell to sense, adapt, and response to a variety of the environments. While advances have been demonstrated in understanding how important FAs are in mediating various biological processes, less is known about how FA composition is regulated and coordinately transduces the specific signals in mediating the distinct biological outcomes, especially cell migration.
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Affiliation(s)
- Jean-Cheng Kuo
- Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan
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22
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Maggi R, Dondi D, Piccolella M, Casulari LA, Martini L. New insight on the molecular aspects of glucocorticoid effects in nervous system development. J Endocrinol Invest 2013; 36:775-80. [PMID: 23765505 DOI: 10.3275/9003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Adrenal glucocorticoids (Gc) are among the most significant hormones in the mammalian organisms; these steroids may reach and penetrate all tissues where they interact with cytoplasmic/nuclear receptors, through which they exert multiple and very multifaceted actions. The effects of physiological concentrations of Gc on brain functions have not been completely clarified, even though Gc are recognized to influence behavioral responses, emotions, cognitive processes and to take part in the neuroendocrine control of body homeostasis. Developmental programming effects of Gc in animal models and humans have been proposed. Actually, pre-natal stress, or exposure to high Gc levels, would somehow affect neuronal developmental events in some structure and this can lead to central nervous system altered functions, as the impairment of neuroendocrine activities, cognitive processes, sleep and mood disorders. Interestingly, it has been observed that these abnormalities may not be limited to the first directly exposed individuals but transmissible across generations. The establishment of animal models with localized pre-natal glucocorticoid receptors deficiency led to the accumulation of data on the possible roles of these hormones on development of the central and peripheral nervous system. The most recent findings on the effects of Gc on neuroblast development, with particular attention to neuronal migration, will be presented.
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Affiliation(s)
- R Maggi
- Department of Pharmacological and Biomolecular Sciences, Section of Biomedicine and Endocrinology, Università degli Studi di Milan, Via G. Balzaretti, 9 - 20133 Milan, Italy.
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23
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Chang KP, Wang CLA, Kao HK, Liang Y, Liu SC, Huang LL, Hseuh C, Hsieh YJ, Chien KY, Chang YS, Yu JS, Chi LM. Overexpression of caldesmon is associated with lymph node metastasis and poorer prognosis in patients with oral cavity squamous cell carcinoma. Cancer 2013; 119:4003-11. [DOI: 10.1002/cncr.28300] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Revised: 06/03/2013] [Accepted: 07/01/2013] [Indexed: 12/15/2022]
Affiliation(s)
- Kai-Ping Chang
- Department of Otolaryngology-Head & Neck Surgery; Chang Gung Memorial Hospital; Tao-Yuan Taiwan
- Molecular Medicine Research Center; Chang Gung University; Tao-Yuan Taiwan
| | - Chih-Lueh Albert Wang
- Muscle and Motility Group; Boston Biomedical Research Institute; Watertown Massachusetts
| | - Huang-Kai Kao
- Department of Plastic and Reconstructive Surgery; Chang Gung Memorial Hospital; Tao-Yuan Taiwan
| | - Ying Liang
- Molecular Medicine Research Center; Chang Gung University; Tao-Yuan Taiwan
| | - Shiau-Chin Liu
- Department of Otolaryngology-Head & Neck Surgery; Chang Gung Memorial Hospital; Tao-Yuan Taiwan
| | - Ling-Ling Huang
- Department of Otolaryngology-Head & Neck Surgery; Chang Gung Memorial Hospital; Tao-Yuan Taiwan
| | - Chuen Hseuh
- Department of Pathology; Chang Gung Memorial Hospital; Tao-Yuan Taiwan
| | - Ya-Ju Hsieh
- Molecular Medicine Research Center; Chang Gung University; Tao-Yuan Taiwan
| | - Kun-Yi Chien
- Department of Biochemistry and Molecular Biology; Chang Gung University; Tao-Yuan Taiwan
| | - Yu-Sun Chang
- Molecular Medicine Research Center; Chang Gung University; Tao-Yuan Taiwan
| | - Jau-Song Yu
- Department of Biochemistry and Molecular Biology; Chang Gung University; Tao-Yuan Taiwan
| | - Lang-Ming Chi
- Molecular Medicine Research Center; Chang Gung University; Tao-Yuan Taiwan
- Department of Medical Research Development; Chang Gung Memorial Hospital; Tao-Yuan Taiwan
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24
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Meola J, Hidalgo GDS, Silva JCRE, Silva LECM, Paz CCP, Ferriani RA. Caldesmon: new insights for diagnosing endometriosis. Biol Reprod 2013; 88:122. [PMID: 23575144 DOI: 10.1095/biolreprod.112.103598] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Considerable effort has been invested in searching for less invasive methods of diagnosing endometriosis. Previous studies have indicated altered levels of the CALD1 gene (encoding the protein caldesmon) in endometriosis. The aims of our study were to investigate whether average CALD1 expression and caldesmon protein levels are differentially altered in the endometrium and endometriotic lesions and to evaluate the performance of the CALD1 gene and caldesmon protein as potential biomarkers for endometriosis. Paired biopsies of endometrial tissue (eutopic endometrium) and endometriotic lesions (ectopic endometrium) were obtained from patients with endometriosis to evaluate CALD1 gene expression and caldesmon protein levels by real-time PCR and Western blot analysis, respectively. In addition, immunostaining for caldesmon to determine cellular localization was also performed. Endometrium from women without endometriosis was used as a control. Increased CALD1 expression and caldesmon levels were detected in the endometriotic lesions. The electrophoretic profile of caldesmon by Western blot analysis was clearly different between the control group (endometrium of women without endometriosis) and the group of women with endometriosis (eutopic endometrium and endometriotic lesions). Caldesmon expression as determined by immunostaining showed no variation among the cell types in endometriotic lesions and eutopic endometrium. Stromal cells marked positively in eutopic endometrium from control patients and in the endometriotic lesions. The presence of caldesmon in the endometrium of patients with and without endometriosis permitted diagnoses with 95% sensitivity (specificity 100%) and 100% sensitivity (specificity 100%) for the disease and for minimal to mild endometriosis in the proliferative phase of the menstrual cycle, respectively. In the secretory phase, minimal to mild endometriosis was detected with 90% sensitivity and 93.3% specificity. Caldesmon is a possible predictor of endometrial dysregulation in patients with endometriosis. A potential limitation of our study is the fact that other endometrial diseases were not excluded, and therefore prospective studies are needed to confirm the potential of caldesmon as a biomarker exclusively for endometriosis.
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Affiliation(s)
- Juliana Meola
- Department of Gynecology and Obstetrics, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil.
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25
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Kuo JC. Mechanotransduction at focal adhesions: integrating cytoskeletal mechanics in migrating cells. J Cell Mol Med 2013; 17:704-12. [PMID: 23551528 PMCID: PMC3823174 DOI: 10.1111/jcmm.12054] [Citation(s) in RCA: 90] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2012] [Accepted: 02/25/2013] [Indexed: 12/22/2022] Open
Abstract
Focal adhesions (FAs) are complex plasma membrane-associated macromolecular assemblies that serve to physically connect the actin cytoskeleton to integrins that engage with the surrounding extracellular matrix (ECM). FAs undergo maturation wherein they grow and change composition differentially to provide traction and to transduce the signals that drive cell migration, which is crucial to various biological processes, including development, wound healing and cancer metastasis. FA-related signalling networks dynamically modulate the strength of the linkage between integrin and actin and control the organization of the actin cytoskeleton. In this review, we have summarized a number of recent investigations exploring how FA composition is affected by the mechanical forces that transduce signalling networks to modulate cellular function and drive cell migration. Understanding the fundamental mechanisms of how force governs adhesion signalling provides insights that will allow the manipulation of cell migration and help to control migration-related human diseases.
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Affiliation(s)
- Jean-Cheng Kuo
- Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan.
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26
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Morita-Ishihara T, Miura M, Iyoda S, Izumiya H, Watanabe H, Ohnishi M, Terajima J. EspO1-2 regulates EspM2-mediated RhoA activity to stabilize formation of focal adhesions in enterohemorrhagic Escherichia coli-infected host cells. PLoS One 2013; 8:e55960. [PMID: 23409096 PMCID: PMC3568036 DOI: 10.1371/journal.pone.0055960] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2012] [Accepted: 01/07/2013] [Indexed: 12/27/2022] Open
Abstract
Enterohemorrhagic Escherichia coli (EHEC) Sakai strain encodes two homologous type III effectors, EspO1-1 and EspO1-2. These EspO1s have amino acid sequence homology with Shigella OspE, which targets integrin-linked kinase to stabilize formation of focal adhesions (FAs). Like OspE, EspO1-1 was localized to FAs in EHEC-infected cells, but EspO1-2 was localized in the cytoplasm. An EHEC ΔespO1-1ΔespO1-2 double mutant induced cell rounding and FA loss in most of infected cells, but neither the ΔespO1-1 nor ΔespO1-2 single mutant did. These results suggested that EspO1-2 functioned in the cytoplasm by a different mechanism from EspO1-1 and OspE. Since several type III effectors modulate Rho GTPase, which contributes to FA formation, we investigated whether EspO1-2 modulates the function of these type III effectors. We identified a direct interaction between EspO1-2 and EspM2, which acts as a RhoA guanine nucleotide exchange factor. Upon ectopic co-expression, EspO1-2 co-localized with EspM2 in the cytoplasm and suppressed EspM2-mediated stress fiber formation. Consistent with these findings, an ΔespO1-1ΔespO1-2ΔespM2 triple mutant did not induce cell rounding in epithelial cells. These results indicated that EspO1-2 interacted with EspM2 to regulate EspM2-mediated RhoA activity and stabilize FA formation during EHEC infection.
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Affiliation(s)
- Tomoko Morita-Ishihara
- Department of Bacteriology I, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan.
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Jang SM, Kim JW, Kim D, Kim CH, An JH, Choi KH, Rhee S. Sox4-mediated caldesmon expression facilitates skeletal myoblast differentiation. J Cell Sci 2013; 126:5178-88. [DOI: 10.1242/jcs.131581] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Caldesmon (CaD), originally identified as an actin-regulatory protein, is involved in the regulation of diverse actin-related signaling processes, including cell migration and proliferation, in various cells. The cellular function of CaD has been studied primarily in the smooth muscle system; nothing is known about its function in skeletal muscle differentiation. In this study, we found that the expression of CaD gradually increased as C2C12 myoblast differentiation progressed. Silencing of CaD inhibited cell spreading and migration, resulting in a decrease in myoblast differentiation. Promoter analysis of the caldesmon gene (CALD1) and gel mobility shift assays identified Sox4 as a major trans-acting factor for the regulation of CALD1 expression during myoblast differentiation. Silencing of Sox4 decreased not only CaD protein synthesis but also myoblast fusion in C2C12 cells and myofibril formation in mouse embryonic muscle. Overexpression of CaD in Sox4-silenced C2C12 cells rescued the differentiation process. These results clearly demonstrate that CaD, regulated by Sox4 transcriptional activity, contributes to skeletal muscle differentiation.
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Kim KH, Yeo SG, Kim WK, Kim DY, Yeo HY, Hong JP, Chang HJ, Park JW, Kim SY, Kim BC, Yoo BC. Up-regulated expression of l-caldesmon associated with malignancy of colorectal cancer. BMC Cancer 2012; 12:601. [PMID: 23241148 PMCID: PMC3572427 DOI: 10.1186/1471-2407-12-601] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2012] [Accepted: 12/09/2012] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Caldesmon (CaD), a major actin-associated protein, is found in smooth muscle and non-muscle cells. Smooth muscle caldesmon, h-CaD, is a multifunctional protein, and non-muscle cell caldesmon, l-CaD, plays a role in cytoskeletal architecture and dynamics. h-CaD is thought to be an useful marker for smooth muscle tumors, but the role(s) of l-CaD has not been examined in tumors. METHODS Primary colon cancer and liver metastasis tissues were obtained from colon cancer patients. Prior to chemoradiotherapy (CRT), normal and cancerous tissues were obtained from rectal cancer patients. Whole-tissue protein extracts were analyzed by 2-DE-based proteomics. Expression and phosphorylation level of main cellular signaling proteins were determined by western blot analysis. Cell proliferation after CaD siRNA transfection was monitored by MTT assay. RESULTS The expression level of l-CaD was significantly increased in primary colon cancer and liver metastasis tissues compared to the level in the corresponding normal tissues. In cancerous tissues obtained from the patients showing poor response to CRT (Dworak grade 4), the expression of l-CaD was increased compared to that of good response group (Dworak grade 1). In line with, l-CaD positive human colon cancer cell lines were more resistant to 5-fluorouracil (5-FU) and radiation treatment compared to l-CaD negative cell lines. Artificial suppression of l-CaD increased susceptibility of colon cancer cells to 5-FU, and caused an increase of p21 and c-PARP, and a decrease of NF-kB and p-mTOR expression. CONCLUSION Up-regulated expression of l-CaD may have a role for increasing metastatic property and decreasing CRT susceptibility in colorectal cancer cells.
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Affiliation(s)
- Kyung-Hee Kim
- Colorectal Cancer Branch, Division of Translational and Clinical Research I, Research Institute, National Cancer Center, Goyang, 410-769, Republic of Korea
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29
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Jayo A, Parsons M, Adams JC. A novel Rho-dependent pathway that drives interaction of fascin-1 with p-Lin-11/Isl-1/Mec-3 kinase (LIMK) 1/2 to promote fascin-1/actin binding and filopodia stability. BMC Biol 2012; 10:72. [PMID: 22883572 PMCID: PMC3488970 DOI: 10.1186/1741-7007-10-72] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Accepted: 08/10/2012] [Indexed: 12/24/2022] Open
Abstract
Background Fascin-1 is an actin crosslinking protein that is important for the assembly of cell protrusions in neurons, skeletal and smooth muscle, fibroblasts, and dendritic cells. Although absent from most normal adult epithelia, fascin-1 is upregulated in many human carcinomas, and is associated with poor prognosis because of its promotion of carcinoma cell migration, invasion, and metastasis. Rac and Cdc42 small guanine triphosphatases have been identified as upstream regulators of the association of fascin-1 with actin, but the possible role of Rho has remained obscure. Additionally, experiments have been hampered by the inability to measure the fascin-1/actin interaction directly in intact cells. We investigated the hypothesis that fascin-1 is a functional target of Rho in normal and carcinoma cells, using experimental approaches that included a novel fluorescence resonance energy transfer (FRET)/fluorescence lifetime imaging (FLIM) method to measure the interaction of fascin-1 with actin. Results Rho activity modulates the interaction of fascin-1 with actin, as detected by a novel FRET method, in skeletal myoblasts and human colon carcinoma cells. Mechanistically, Rho regulation depends on Rho kinase activity, is independent of the status of myosin II activity, and is not mediated by promotion of the fascin/PKC complex. The p-Lin-11/Isl-1/Mec-3 kinases (LIMK), LIMK1 and LIMK2, act downstream of Rho kinases as novel binding partners of fascin-1, and this complex regulates the stability of filopodia. Conclusions We have identified a novel activity of Rho in promoting a complex between fascin-1 and LIMK1/2 that modulates the interaction of fascin-1 with actin. These data provide new mechanistic insight into the intracellular coordination of contractile and protrusive actin-based structures. During the course of the study, we developed a novel FRET method for analysis of the fascin-1/actin interaction, with potential general applicability for analyzing the activities of actin-binding proteins in intact cells.
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Affiliation(s)
- Asier Jayo
- Randall Division of Cell and Molecular Biophysics, King's College London, Guy's Campus, London SE1 1UL, UK
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Jensen MH, Morris EJ, Huang R, Rebowski G, Dominguez R, Weitz DA, Moore JR, Wang CLA. The conformational state of actin filaments regulates branching by actin-related protein 2/3 (Arp2/3) complex. J Biol Chem 2012; 287:31447-53. [PMID: 22791711 DOI: 10.1074/jbc.m112.350421] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Actin is a highly ubiquitous protein in eukaryotic cells that plays a crucial role in cell mechanics and motility. Cell motility is driven by assembling actin as polymerizing actin drives cell protrusions in a process closely involving a host of other actin-binding proteins, notably the actin-related protein 2/3 (Arp2/3) complex, which nucleates actin and forms branched filamentous structures. The Arp2/3 complex preferentially binds specific actin networks at the cell leading edge and forms branched filamentous structures, which drive cell protrusions, but the exact regulatory mechanism behind this process is not well understood. Here we show using in vitro imaging and binding assays that a fragment of the actin-binding protein caldesmon added to polymerizing actin increases the Arp2/3-mediated branching activity, whereas it has no effect on branch formation when binding to aged actin filaments. Because this caldesmon effect is shown to be independent of nucleotide hydrolysis and phosphate release from actin, our results suggest a mechanism by which caldesmon maintains newly polymerized actin in a distinct state that has a higher affinity for the Arp2/3 complex. Our data show that this new state does not affect the level of cooperativity of binding by Arp2/3 complex or its distribution on actin. This presents a novel regulatory mechanism by which caldesmon, and potentially other actin-binding proteins, regulates the interactions of actin with its binding partners.
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Affiliation(s)
- Mikkel Herholdt Jensen
- Department of Physiology and Biophysics, Boston University, Boston, Massachusetts 02118, USA
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Tojkander S, Gateva G, Lappalainen P. Actin stress fibers--assembly, dynamics and biological roles. J Cell Sci 2012; 125:1855-64. [PMID: 22544950 DOI: 10.1242/jcs.098087] [Citation(s) in RCA: 515] [Impact Index Per Article: 42.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Actin filaments assemble into diverse protrusive and contractile structures to provide force for a number of vital cellular processes. Stress fibers are contractile actomyosin bundles found in many cultured non-muscle cells, where they have a central role in cell adhesion and morphogenesis. Focal-adhesion-anchored stress fibers also have an important role in mechanotransduction. In animal tissues, stress fibers are especially abundant in endothelial cells, myofibroblasts and epithelial cells. Importantly, recent live-cell imaging studies have provided new information regarding the mechanisms of stress fiber assembly and how their contractility is regulated in cells. In addition, these studies might elucidate the general mechanisms by which contractile actomyosin arrays, including muscle cell myofibrils and cytokinetic contractile ring, can be generated in cells. In this Commentary, we discuss recent findings concerning the physiological roles of stress fibers and the mechanism by which these structures are generated in cells.
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Affiliation(s)
- Sari Tojkander
- Institute of Biotechnology, University of Helsinki, Finland
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ABRAMS J, DAVULURI G, SEILER C, PACK M. Smooth muscle caldesmon modulates peristalsis in the wild type and non-innervated zebrafish intestine. Neurogastroenterol Motil 2012; 24:288-99. [PMID: 22316291 PMCID: PMC3919438 DOI: 10.1111/j.1365-2982.2011.01844.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
BACKGROUND The high molecular weight isoform of the actin-binding protein Caldesmon (h-CaD) regulates smooth muscle contractile function by modulating cross-bridge cycling of myosin heads. The normal inhibitory activity of h-CaD is regulated by the enteric nervous system; however, the role of h-CaD during intestinal peristalsis has never been studied. METHODS We identified a zebrafish paralog of the human CALD1 gene that encodes an h-CaD isoform expressed in intestinal smooth muscle. We examined the role of h-CaD during intestinal peristalsis in zebrafish larvae by knocking down the h-CaD protein using an antisense morpholino oligonucleotide. We also developed transgenic zebrafish that express inhibitory peptides derived from the h-CaD myosin and actin-binding domains, and examined their effect on peristalsis in wild-type zebrafish larvae and sox10 (colourless) mutant larvae that lack enteric nerves. KEY RESULTS Genomic analyses identified two zebrafish Caldesmon paralogs. The cald1a ortholog encoded a high molecular weight isoform generated by alternative splicing whose intestinal expression was restricted to smooth muscle. Propulsive intestinal peristalsis was increased in wild-type zebrafish larvae by h-CaD knockdown and by expression of transgenes encoding inhibitory myosin and actin-binding domain peptides. Peristalsis in the non-innervated intestine of sox10 (colourless) larvae was partially restored by h-CaD knockdown and expression of the myosin-binding peptide. CONCLUSIONS & INFERENCES Disruption of the normal inhibitory function of h-CaD enhances intestinal peristalsis in both wild-type zebrafish larvae and mutant larvae that lack enteric nerves, thus confirming a physiologic role for regulation of smooth muscle contraction at the actin filament.
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Affiliation(s)
- J. ABRAMS
- Department of Medicine, University of Pennsylvania School
of Medicine, Philadelphia, PA, USA
| | - G. DAVULURI
- Department of Medicine, University of Pennsylvania School
of Medicine, Philadelphia, PA, USA
| | - C. SEILER
- Department of Medicine, University of Pennsylvania School
of Medicine, Philadelphia, PA, USA
| | - M. PACK
- Department of Medicine, University of Pennsylvania School
of Medicine, Philadelphia, PA, USA,Department of Cell and Developmental Biology,
University of Pennsylvania School of Medicine, Philadelphia, PA, USA
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At the Start of the Sarcomere: A Previously Unrecognized Role for Myosin Chaperones and Associated Proteins during Early Myofibrillogenesis. Biochem Res Int 2012; 2012:712315. [PMID: 22400118 PMCID: PMC3287041 DOI: 10.1155/2012/712315] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Accepted: 10/10/2011] [Indexed: 01/03/2023] Open
Abstract
The development of striated muscle in vertebrates requires the assembly of contractile myofibrils, consisting of highly ordered bundles of protein filaments. Myofibril formation occurs by the stepwise addition of complex proteins, a process that is mediated by a variety of molecular chaperones and quality control factors. Most notably, myosin of the thick filament requires specialized chaperone activity during late myofibrillogenesis, including that of Hsp90 and its cofactor, Unc45b. Unc45b has been proposed to act exclusively as an adaptor molecule, stabilizing interactions between Hsp90 and myosin; however, recent discoveries in zebrafish and C. elegans suggest the possibility of an earlier role for Unc45b during myofibrillogenesis. This role may involve functional control of nonmuscle myosins during the earliest stages of myogenesis, when premyofibril scaffolds are first formed from dynamic cytoskeletal actin. This paper will outline several lines of evidence that converge to build a model for Unc45b activity during early myofibrillogenesis.
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Nie S, Kee Y, Bronner-Fraser M. Caldesmon regulates actin dynamics to influence cranial neural crest migration in Xenopus. Mol Biol Cell 2011; 22:3355-65. [PMID: 21795398 PMCID: PMC3172261 DOI: 10.1091/mbc.e11-02-0165] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
A nonmuscle caldesmon (CaD) is highly expressed in premigratory and migrating Xenopus cranial neural crest cells. A loss-of-function approach shows that CaD is critical for neural crest migration. The results further suggest that CaD influences cell morphology and motility by modulating actin dynamics in neural crest cells. Caldesmon (CaD) is an important actin modulator that associates with actin filaments to regulate cell morphology and motility. Although extensively studied in cultured cells, there is little functional information regarding the role of CaD in migrating cells in vivo. Here we show that nonmuscle CaD is highly expressed in both premigratory and migrating cranial neural crest cells of Xenopus embryos. Depletion of CaD with antisense morpholino oligonucleotides causes cranial neural crest cells to migrate a significantly shorter distance, prevents their segregation into distinct migratory streams, and later results in severe defects in cartilage formation. Demonstrating specificity, these effects are rescued by adding back exogenous CaD. Interestingly, CaD proteins with mutations in the Ca2+-calmodulin–binding sites or ErK/Cdk1 phosphorylation sites fail to rescue the knockdown phenotypes, whereas mutation of the PAK phosphorylation site is able to rescue them. Analysis of neural crest explants reveals that CaD is required for the dynamic arrangements of actin and, thus, for cell shape changes and process formation. Taken together, these results suggest that the actin-modulating activity of CaD may underlie its critical function and is regulated by distinct signaling pathways during normal neural crest migration.
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Affiliation(s)
- Shuyi Nie
- Division of Biology, California Institute of Technology, Pasadena, CA 91125, USA
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The role of the microenvironment in tumor growth and invasion. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2011; 106:353-79. [PMID: 21736894 DOI: 10.1016/j.pbiomolbio.2011.06.006] [Citation(s) in RCA: 109] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Mathematical modeling and computational analysis are essential for understanding the dynamics of the complex gene networks that control normal development and homeostasis, and can help to understand how circumvention of that control leads to abnormal outcomes such as cancer. Our objectives here are to discuss the different mechanisms by which the local biochemical and mechanical microenvironment, which is comprised of various signaling molecules, cell types and the extracellular matrix (ECM), affects the progression of potentially-cancerous cells, and to present new results on two aspects of these effects. We first deal with the major processes involved in the progression from a normal cell to a cancerous cell at a level accessible to a general scientific readership, and we then outline a number of mathematical and computational issues that arise in cancer modeling. In Section 2 we present results from a model that deals with the effects of the mechanical properties of the environment on tumor growth, and in Section 3 we report results from a model of the signaling pathways and the tumor microenvironment (TME), and how their interactions affect the development of breast cancer. The results emphasize anew the complexities of the interactions within the TME and their effect on tumor growth, and show that tumor progression is not solely determined by the presence of a clone of mutated immortal cells, but rather that it can be 'community-controlled'.
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36
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Zilberman Y, Alieva NO, Miserey-Lenkei S, Lichtenstein A, Kam Z, Sabanay H, Bershadsky A. Involvement of the Rho-mDia1 pathway in the regulation of Golgi complex architecture and dynamics. Mol Biol Cell 2011; 22:2900-11. [PMID: 21680709 PMCID: PMC3154885 DOI: 10.1091/mbc.e11-01-0007] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
A study of the role of actin cytoskeleton regulation in Golgi organization and function shows that Rho regulates Golgi fragmentation into ministacks, as well as formation of Rab6-positive Golgi-derived vesicles, via mDia1 formin activation. The Rho–mDia1 pathway affects the Golgi complex by controlling fusion and fission of Golgi membranes. In mammalian cells, the Golgi apparatus is a ribbon-like, compact structure composed of multiple membrane stacks connected by tubular bridges. Microtubules are known to be important to Golgi integrity, but the role of the actin cytoskeleton in the maintenance of Golgi architecture remains unclear. Here we show that an increase in Rho activity, either by treatment of cells with lysophosphatidic acid or by expression of constitutively active mutants, resulted in pronounced fragmentation of the Golgi complex into ministacks. Golgi dispersion required the involvement of mDia1 formin, a downstream target of Rho and a potent activator of actin polymerization; moreover, constitutively active mDia1, in and of itself, was sufficient for Golgi dispersion. The dispersion process was accompanied by formation of dynamic F-actin patches in the Golgi area. Experiments with cytoskeletal inhibitors (e.g., latrunculin B, blebbistatin, and Taxol) revealed that actin polymerization, myosin-II–driven contractility, and microtubule-based intracellular movement were all involved in the process of Golgi dispersion induced by Rho–mDia1 activation. Live imaging of Golgi recovery revealed that fusion of the small Golgi stacks into larger compartments was repressed in cells with active mDia1. Furthermore, the formation of Rab6-positive transport vesicles derived from the Golgi complex was enhanced upon activation of the Rho–mDia1 pathway. Transient localization of mDia1 to Rab6-positive vesicles was detected in cells expressing active RhoA. Thus, the Rho–mDia1 pathway is involved in regulation of the Golgi structure, affecting remodeling of Golgi membranes.
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Affiliation(s)
- Yuliya Zilberman
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel
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37
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A Molecular Pathway for Myosin II Recruitment to Stress Fibers. Curr Biol 2011; 21:539-50. [DOI: 10.1016/j.cub.2011.03.007] [Citation(s) in RCA: 206] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2010] [Revised: 02/02/2011] [Accepted: 03/02/2011] [Indexed: 11/17/2022]
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Millioni R, Iori E, Lenzini L, Puricelli L, Caroccia B, Arrigoni G, Rossi GP, Tessari P. Caldesmon over-expression in type 1 diabetic nephropathy. J Diabetes Complications 2011; 25:114-21. [PMID: 20801058 DOI: 10.1016/j.jdiacomp.2010.07.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2009] [Revised: 07/02/2010] [Accepted: 07/13/2010] [Indexed: 01/27/2023]
Abstract
Substantial evidence supports a genetic susceptibility to develop nephropathy in type 1 diabetes and a key pathogenic role of actin cytoskeleton dysfunction in this complication. We previously reported that many cytoskeletal proteins were either up- or down-regulated in fibroblast cells from type 1 diabetic (T1DM) patients with nephropathy. The gene of one of these proteins, caldesmon, lies in a chromosomal region linked to nephropathy and its promoter region contains a single nucleotide polymorphism that is associated with nephropathy. Hence, we analyzed caldesmon gene and protein expression in cultured fibroblasts from T1DM patients with and without nephropathy and from control subjects. Caldesmon gene was studied in cells cultured under normal glucose levels by quantitative real-time RT-PCR. Caldesmon protein isoforms were quantified both under normal and high glucose conditions by two-dimensional electrophoresis. Caldesmon gene was over-expressed in fibroblasts from diabetic patients with nephropathy, in comparison to both those from diabetic patients without nephropathy and those from controls. We quantified six caldesmon protein isoforms, two of them were increased whereas another one was decreased only in fibroblasts from diabetic patients with nephropathy. None of these isoforms showed any difference in their relative abundance in response to high glucose. Variable results in response to high glucose were observed in the expression of other proteins in the three experimental groups. Our data lend further support to an involvement of caldesmon in the susceptibility to diabetic nephropathy in type 1 diabetes, independently from environmental glucose levels.
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Affiliation(s)
- Renato Millioni
- Department of Clinical and Experimental Medicine, University of Padova, Italy
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Mayanagi T, Sobue K. Diversification of caldesmon-linked actin cytoskeleton in cell motility. Cell Adh Migr 2011; 5:150-9. [PMID: 21350330 DOI: 10.4161/cam.5.2.14398] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The actin cytoskeleton plays a key role in regulating cell motility. Caldesmon (CaD) is an actin-linked regulatory protein found in smooth muscle and non-muscle cells that is conserved among a variety of vertebrates. It binds and stabilizes actin filaments, as well as regulating actin-myosin interaction in a calcium (Ca2+)/calmodulin (CaM)- and/or phosphorylation-dependent manner. CaD function is regulated qualitatively by Ca2+/CaM and by its phosphorylation state and quantitatively at the mRNA level, by three different transcriptional regulation of the CALD1 gene. CaD has numerous functions in cell motility, such as migration, invasion, and proliferation, exerted via the reorganization of the actin cytoskeleton. Here we will outline recent findings regarding CaD's structural features and functions.
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Affiliation(s)
- Taira Mayanagi
- Department of Neuroscience, Osaka University Graduate School of Medicine, Osaka, Japan
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p38 MAP kinase mediates burn serum-induced endothelial barrier dysfunction: involvement of F-actin rearrangement and L-caldesmon phosphorylation. Shock 2011; 34:222-8. [PMID: 20160665 DOI: 10.1097/shk.0b013e3181d75a66] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The aim of this study was to test the hypothesis that circulating factors released after a severe burn cause endothelial barrier dysfunction by triggering endothelial cell (EC) contraction through a p38 mitogen-activated protein (MAP) kinase-dependent mechanism. Human umbilical vein ECs (ECV304 cell line) were cultured to create a monolayer of cells that were then cultured with 20% human normal or burn serum. Monolayer permeability was measured by the influx of labeled albumin across the cells. Endothelial cells contraction was determined by alterations of cell surface area and formation of intracellular gaps. P38 MAP kinase activation, F-actin arrangement, and L-caldesmon phosphorylation were assessed by Western blots or immunofluorescence staining. These studies showed that exposure to burn serum resulted in a significant increase in endothelial permeability in a time-dependent manner, which was paralleled by a rapid and persistent activation of p38 MAP kinases. Morphologically, increased intercellular gaps, reduced cell surface area, and a unique rearrangement of F-actin cytoskeleton were observed in burn serum-treated ECs. Inhibition of p38 MAP kinase suppressed the rearrangement of F-actin cytoskeleton, reduced the occurrence of burn serum-induced formation of intercellular gaps, and ameliorated endothelial hyperpermeability. Further study showed that phosphorylation of L-caldesmon was enhanced in burn serum-treated cells via p38 MAP kinase; overexpression of L-caldesmon by adenovirus transfection, however, attenuated the increase in endothelial permeability by burn serum challenge. Collectively, these results have demonstrated for the first time that p38 MAP kinase is an important participant in mediating burn serum-induced endothelial barrier dysfunction through rearrangement of the F-actin cytoskeleton and phosphorylation of L-caldesmon. Inhibition of p38 MAP kinase in vivo, thus, would be a promising therapeutic strategy in ameliorating burn shock development.
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Rikitake Y, Takai Y. Directional Cell Migration. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2011; 287:97-143. [DOI: 10.1016/b978-0-12-386043-9.00003-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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Clause KC, Liu LJ, Tobita K. Directed stem cell differentiation: the role of physical forces. ACTA ACUST UNITED AC 2010; 17:48-54. [PMID: 20560867 DOI: 10.3109/15419061.2010.492535] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
A number of factors contribute to the control of stem cell fate. In particular, the evidence for how physical forces control the stem cell differentiation program is now accruing. In this review, the authors discuss the types of physical forces: mechanical forces, cell shape, extracellular matrix geometry/properties, and cell-cell contacts and morphogenic factors, which evidence suggests play a role in influencing stem cell fate.
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Affiliation(s)
- Kelly C Clause
- Cardiovascular Development Research Program, Children's Hospital of Pittsburgh of University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
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44
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Chen B, Gao H. Mechanical principle of enhancing cell-substrate adhesion via pre-tension in the cytoskeleton. Biophys J 2010; 98:2154-62. [PMID: 20483323 PMCID: PMC2872275 DOI: 10.1016/j.bpj.2010.02.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2009] [Revised: 01/13/2010] [Accepted: 02/01/2010] [Indexed: 01/27/2023] Open
Abstract
Motivated by our earlier study on the effect of pre-tension in gecko adhesion, here we investigate whether and how pre-tension in cytoskeleton influences cell adhesion by developing a stochastic-elasticity model of a stress fiber attached on a rigid substrate via molecular bonds. By comparing the variations in adhesion lifetime and observing the sequences of bond breaking with and without pre-tension in the stress fiber under the same applied force, we demonstrate that the effect of pre-tension is to shift the interfacial failure mode from cracklike propagation toward uniform bond failure within the contact region, thereby greatly increasing the adhesion lifetime. Since stress fibers are the primary load-bearing components of cells, as well as the basic functional units of cytoskeleton that facilitate cell adhesion, this study suggests a feasible mechanism by which cell adhesion could be actively controlled via cytoskeletal contractility and proposes that pre-tension may be a general principle in biological adhesion.
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Affiliation(s)
- Bin Chen
- †Engineering Mechanics, Institute of High Performance Computing, A∗STAR, Singapore
- Corresponding author
| | - Huajian Gao
- ‡Division of Engineering, Brown University, Providence, Rhode Island
- Corresponding author
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Wolfenson H, Henis YI, Geiger B, Bershadsky AD. The heel and toe of the cell's foot: a multifaceted approach for understanding the structure and dynamics of focal adhesions. ACTA ACUST UNITED AC 2010; 66:1017-29. [PMID: 19598236 DOI: 10.1002/cm.20410] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Focal adhesions (FAs) are large clusters of transmembrane receptors of the integrin family and a multitude of associated cytoplasmic "plaque" proteins, which connect the extracellular matrix-bound receptors with the actin cytoskeleton. The formation of nearly stationary FAs defines a boundary between the dense and highly dynamic actin network in lamellipodium and the sparser and more diverse cytoskeletal organization in the lamella proper, creating a template for the organization of the entire actin network. The major "mechanical" and "sensory" functions of FAs; namely, the nucleation and regulation of the contractile, myosin-II-containing stress fibers and the mechanosensing of external surfaces depend, to a major extent, on the dynamics of molecular components within FAs. A central element in FA regulation concerns the positive feedback loop, based on the most intriguing feature of FAs; that is, their dependence on mechanical tension developing by the growing stress fibers. FAs grow in response to such tension, and rapidly disassemble upon its relaxation. In this article, we address the mechanistic relationships between the process of FA development, maturation and dissociation and the dynamic molecular events, which take place in different regions of the FA, primarily in the distal end of this structure (the "toe") and the proximal "heel," and discuss the central role of local mechanical forces in orchestrating the complex interplay between FAs and the actin system.
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Affiliation(s)
- Haguy Wolfenson
- Department of Neurobiology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
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Diez G, Kollmannsberger P, Mierke CT, Koch TM, Vali H, Fabry B, Goldmann WH. Anchorage of vinculin to lipid membranes influences cell mechanical properties. Biophys J 2010; 97:3105-12. [PMID: 20006947 DOI: 10.1016/j.bpj.2009.09.039] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2008] [Revised: 08/24/2009] [Accepted: 09/18/2009] [Indexed: 10/20/2022] Open
Abstract
The focal adhesion protein vinculin (1066 residues) can be separated into a 95-kDa head and a 30-kDa tail domain. Vinculin's lipid binding sites localized on the tail, helix 3 (residues 944-978) and the unstructured C-terminal arm (residues 1052-1066, the so-called lipid anchor), influence focal adhesion turnover and are important for cell migration and adhesion. Using magnetic tweezers, we characterized the cell mechanical behavior in mouse embryonic fibroblast (MEF)-vin(-/-) cells transfected with EGFP-linked-vinculin deficient of the lipid anchor (vinDeltaC, residues 1-1051). MEF-vinDeltaC cells incubated with fibronectin-coated paramagnetic beads were less stiff, and more beads detached during these experiments compared to MEF-rescue cells. Cells expressing vinDeltaC formed fewer focal contacts as determined by confocal microscopy. Two-dimensional traction measurements showed that MEF-vinDeltaC cells generate less force compared to rescue cells. Attenuated traction forces were also found in cells that expressed vinculin with point mutations (R1060 and K1061 to Q) of the lipid anchor that impaired lipid binding. However, traction generation was not diminished in cells that expressed vinculin with impaired lipid binding caused by point mutations on helix 3. Mutating the src-phosphorylation site (Y1065 to F) resulted in reduced traction generation. These observations show that both the lipid binding and the src-phosphorylation of vinculin's C-terminus are important for cell mechanical behavior.
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Affiliation(s)
- Gerold Diez
- Center for Medical Physics and Technology, Biophysics Group, Friedrich-Alexander-University of Erlangen-Nuremberg, Erlangen, Germany
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Jiang Q, Huang R, Cai S, Wang CLA. Caldesmon regulates the motility of vascular smooth muscle cells by modulating the actin cytoskeleton stability. J Biomed Sci 2010; 17:6. [PMID: 20128924 PMCID: PMC2846900 DOI: 10.1186/1423-0127-17-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2009] [Accepted: 02/03/2010] [Indexed: 02/16/2023] Open
Abstract
Background Migration of vascular smooth muscle cells (SMCs) from the media to intima constitutes a critical step in the development of proliferative vascular diseases. To elucidate the regulatory mechanism of vacular SMC motility, the roles of caldesmon (CaD) and its phosphorylation were investigated. Methods We have performed Transwell migration assays, immunofluorescence microscopy, traction microscopy and cell rounding assays using A7r5 cells transfected with EGFP (control), EGFP-wtCaD or phosphomimetic CaD mutants, including EGFP-A1A2 (the two PAK sites Ser452 and Ser482 converted to Ala), EGFP-A3A4 (the two Erk sites Ser497 and Ser527 converted to Ala), EGFP-A1234 (both PAK- and Erk-sites converted to Ala) and EGFP-D1234 (both PAK- and Erk-sites converted to Asp). Results We found that cells transfected with wtCaD, A1A2 or A3A4 mutants of CaD migrated at a rate approximately 50% more slowly than those EGFP-transfected cells. The migration activity for A1234 cells was only about 13% of control cells. Thus it seems both MAPK and PAK contribute to the motility of A7r5 cells and the effects are comparable and additive. The A1234 mutant also gave rise to highest strain energy and lowest rate of cell rounding. The migratory and contractile properties of these cells are consistent with stabilized actin cytoskeletal structures. Indeed, the A1234 mutant cells exhibited most robust stress fibers, whereas cells transfected with wtCaD or A3A4 (and A1A2) had moderately reinforced actin cytoskeleton. The control cells (transfected with EGFP alone) exhibited actin cytoskeleton that was similar to that in untransfected cells, and also migrated at about the same speed as the untransfected cells. Conclusions These results suggest that both the expression level and the level of MAPK- and/or PAK-mediated phosphorylation of CaD play key roles in regulating the cell motility by modulating the actin cytoskeleton stability in dedifferentiated vascular SMCs such as A7r5.
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Affiliation(s)
- Qifeng Jiang
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044, China
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Cai Y, Rossier O, Gauthier NC, Biais N, Fardin MA, Zhang X, Miller LW, Ladoux B, Cornish VW, Sheetz MP. Cytoskeletal coherence requires myosin-IIA contractility. J Cell Sci 2010; 123:413-23. [PMID: 20067993 DOI: 10.1242/jcs.058297] [Citation(s) in RCA: 156] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Maintaining a physical connection across cytoplasm is crucial for many biological processes such as matrix force generation, cell motility, cell shape and tissue development. However, in the absence of stress fibers, the coherent structure that transmits force across the cytoplasm is not understood. We find that nonmuscle myosin-II (NMII) contraction of cytoplasmic actin filaments establishes a coherent cytoskeletal network irrespective of the nature of adhesive contacts. When NMII activity is inhibited during cell spreading by Rho kinase inhibition, blebbistatin, caldesmon overexpression or NMIIA RNAi, the symmetric traction forces are lost and cell spreading persists, causing cytoplasm fragmentation by membrane tension that results in 'C' or dendritic shapes. Moreover, local inactivation of NMII by chromophore-assisted laser inactivation causes local loss of coherence. Actin filament polymerization is also required for cytoplasmic coherence, but microtubules and intermediate filaments are dispensable. Loss of cytoplasmic coherence is accompanied by loss of circumferential actin bundles. We suggest that NMIIA creates a coherent actin network through the formation of circumferential actin bundles that mechanically link elements of the peripheral actin cytoskeleton where much of the force is generated during spreading.
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Affiliation(s)
- Yunfei Cai
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
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Sen S, Kumar S. Combining mechanical and optical approaches to dissect cellular mechanobiology. J Biomech 2010; 43:45-54. [PMID: 19819457 PMCID: PMC2813341 DOI: 10.1016/j.jbiomech.2009.09.008] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/21/2009] [Indexed: 01/27/2023]
Abstract
Mechanical force modulates a wide array of cell physiological processes. Cells sense and respond to mechanical stimuli using a hierarchy of structural complexes spanning multiple length scales, including force-sensitive molecules and cytoskeletal networks. Understanding mechanotransduction, i.e., the process by which cells convert mechanical inputs into biochemical signals, has required the development of novel biophysical tools that allow for probing of cellular and subcellular components at requisite time, length, and force scales and technologies that track the spatio-temporal dynamics of relevant biomolecules. In this review, we begin by discussing the underlying principles and recent applications of atomic force microscopy, magnetic twisting cytometry, and traction force microscopy, three tools that have been widely used for measuring the mechanical properties of cells and for probing the molecular basis of cellular mechanotransduction. We then discuss how such tools can be combined with advanced fluorescence methods for imaging biochemical processes in living cells in the context of three specific problem spaces. We first focus on fluorescence resonance energy transfer, which has enabled imaging of intra- and inter-molecular interactions and enzymatic activity in real time based on conformational changes in sensor molecules. Next, we examine the use of fluorescence methods to probe force-dependent dynamics of focal adhesion proteins. Finally, we discuss the use of calcium ratiometric signaling to track fast mechanotransductive signaling dynamics. Together, these studies demonstrate how single-cell biomechanical tools can be effectively combined with molecular imaging technologies for elucidating mechanotransduction processes and identifying mechanosensitive proteins.
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Affiliation(s)
- Shamik Sen
- Department of Bioengineering, 274A Stanley Hall #1762, University of California, Berkeley, CA 94720-1762, USA
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Wang CLA, Coluccio LM. New insights into the regulation of the actin cytoskeleton by tropomyosin. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2010; 281:91-128. [PMID: 20460184 DOI: 10.1016/s1937-6448(10)81003-2] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The actin cytoskeleton is regulated by a variety of actin-binding proteins including those constituting the tropomyosin family. Tropomyosins are coiled-coil dimers that bind along the length of actin filaments. In muscles, tropomyosin regulates the interaction of actin-containing thin filaments with myosin-containing thick filaments to allow contraction. In nonmuscle cells where multiple tropomyosin isoforms are expressed, tropomyosins participate in a number of cellular events involving the cytoskeleton. This chapter reviews the current state of the literature regarding tropomyosin structure and function and discusses the evidence that tropomyosins play a role in regulating actin assembly.
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