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Triandafillou CG, Pan RW, Dinner AR, Drummond DA. Pervasive, conserved secondary structure in highly charged protein regions. PLoS Comput Biol 2023; 19:e1011565. [PMID: 37844070 PMCID: PMC10602382 DOI: 10.1371/journal.pcbi.1011565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 10/26/2023] [Accepted: 10/02/2023] [Indexed: 10/18/2023] Open
Abstract
Understanding how protein sequences confer function remains a defining challenge in molecular biology. Two approaches have yielded enormous insight yet are often pursued separately: structure-based, where sequence-encoded structures mediate function, and disorder-based, where sequences dictate physicochemical and dynamical properties which determine function in the absence of stable structure. Here we study highly charged protein regions (>40% charged residues), which are routinely presumed to be disordered. Using recent advances in structure prediction and experimental structures, we show that roughly 40% of these regions form well-structured helices. Features often used to predict disorder-high charge density, low hydrophobicity, low sequence complexity, and evolutionarily varying length-are also compatible with solvated, variable-length helices. We show that a simple composition classifier predicts the existence of structure far better than well-established heuristics based on charge and hydropathy. We show that helical structure is more prevalent than previously appreciated in highly charged regions of diverse proteomes and characterize the conservation of highly charged regions. Our results underscore the importance of integrating, rather than choosing between, structure- and disorder-based approaches.
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Affiliation(s)
- Catherine G. Triandafillou
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Rosalind Wenshan Pan
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California, United States of America
| | - Aaron R. Dinner
- Department of Chemistry, University of Chicago, Chicago, Illinois, United States of America
| | - D. Allan Drummond
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois, United States of America
- Department of Medicine, Section of Genetic Medicine, The University of Chicago, Chicago, Illinois, United States of America
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2
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Triandafillou CG, Pan RW, Dinner AR, Drummond DA. Pervasive, conserved secondary structure in highly charged protein regions. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.15.528637. [PMID: 36824805 PMCID: PMC9949069 DOI: 10.1101/2023.02.15.528637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
Understanding how protein sequences confer function remains a defining challenge in molecular biology. Two approaches have yielded enormous insight yet are often pursued separately: structure-based, where sequence-encoded structures mediate function, and disorder-based, where sequences dictate physicochemical and dynamical properties which determine function in the absence of stable structure. Here we study highly charged protein regions (>40% charged residues), which are routinely presumed to be disordered. Using recent advances in structure prediction and experimental structures, we show that roughly 40% of these regions form well-structured helices. Features often used to predict disorder-high charge density, low hydrophobicity, low sequence complexity, and evolutionarily varying length-are also compatible with solvated, variable-length helices. We show that a simple composition classifier predicts the existence of structure far better than well-established heuristics based on charge and hydropathy. We show that helical structure is more prevalent than previously appreciated in highly charged regions of diverse proteomes and characterize the conservation of highly charged regions. Our results underscore the importance of integrating, rather than choosing between, structure- and disorder-based approaches.
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Affiliation(s)
| | - Rosalind Wenshan Pan
- Department of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA
| | | | - D. Allan Drummond
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL
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3
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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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4
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Pütz S, Barthel LS, Frohn M, Metzler D, Barham M, Pryymachuk G, Trunschke O, Lubomirov LT, Hescheler J, Chalovich JM, Neiss WF, Koch M, Schroeter MM, Pfitzer G. Caldesmon ablation in mice causes umbilical herniation and alters contractility of fetal urinary bladder smooth muscle. J Gen Physiol 2021; 153:212279. [PMID: 34115104 PMCID: PMC8203487 DOI: 10.1085/jgp.202012776] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 04/21/2021] [Indexed: 12/13/2022] Open
Abstract
The actin-, myosin-, and calmodulin-binding protein caldesmon (CaD) is expressed in two splice isoforms: h-CaD, which is an integral part of the actomyosin domain of smooth muscle cells, and l-CaD, which is widely expressed and is involved in many cellular functions. Despite extensive research for many years, CaD's in vivo function has remained elusive. To explore the role of CaD in smooth muscle contraction in vivo, we generated a mutant allele that ablates both isoforms. Heterozygous animals were viable and had a normal life span, but homozygous mutants died perinatally, likely because of a persistent umbilical hernia. The herniation was associated with hypoplastic and dysmorphic abdominal wall muscles. We assessed mechanical parameters in isometrically mounted longitudinal strips of E18.5 urinary bladders and in ring preparations from abdominal aorta using wire myography. Ca2+ sensitivity was higher and relaxation rate was slower in Cald1−/− compared with Cald1+/+ skinned bladder strips. However, we observed no change in the content and phosphorylation of regulatory proteins of the contractile apparatus and myosin isoforms known to affect these contractile parameters. Intact fibers showed no difference in actin and myosin content, regardless of genotype, although KCl-induced force tended to be lower in homozygous and higher in heterozygous mutants than in WTs. Conversely, in skinned fibers, myosin content and maximal force were significantly lower in Cald1−/− than in WTs. In KO abdominal aortas, resting and U46619 elicited force were lower than in WTs. Our results are consistent with the notion that CaD impacts smooth muscle function dually by (1) acting as a molecular brake on contraction and (2) maintaining the structural integrity of the contractile machinery. Most importantly, CaD is essential for resolution of the physiological umbilical hernia and ventral body wall closure.
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Affiliation(s)
- Sandra Pütz
- Institute of Vegetative Physiology, Center of Physiology, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Lisa Sophie Barthel
- Institute of Vegetative Physiology, Center of Physiology, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Marina Frohn
- Institute of Vegetative Physiology, Center of Physiology, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Doris Metzler
- Institute of Vegetative Physiology, Center of Physiology, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Mohammed Barham
- Institute of Anatomy I, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Galyna Pryymachuk
- Institute of Anatomy I, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Oliver Trunschke
- Institute of Vegetative Physiology, Center of Physiology, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Lubomir T Lubomirov
- Institute of Vegetative Physiology, Center of Physiology, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Jürgen Hescheler
- Institute of Neurophysiology, Center of Physiology, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Joseph M Chalovich
- Department of Biochemistry & Molecular Biology, Brody School of Medicine at East Carolina University, Greenville, NC
| | - Wolfram F Neiss
- Institute of Anatomy I, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Manuel Koch
- Institute for Dental Research and Oral Musculoskeletal Biology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Mechthild M Schroeter
- Institute of Vegetative Physiology, Center of Physiology, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Gabriele Pfitzer
- Institute of Vegetative Physiology, Center of Physiology, Faculty of Medicine, University of Cologne, Cologne, Germany
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Pham AK, Miller M, Rosenthal P, Das S, Weng N, Jang S, Kurten RC, Badrani J, Doherty TA, Oliver B, Broide DH. ORMDL3 expression in ASM regulates hypertrophy, hyperplasia via TPM1 and TPM4, and contractility. JCI Insight 2021; 6:136911. [PMID: 33661765 PMCID: PMC8119187 DOI: 10.1172/jci.insight.136911] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 02/26/2021] [Indexed: 12/21/2022] Open
Abstract
ORM1-like 3 (ORMDL3) has strong genetic linkage to childhood onset asthma. To determine whether ORMDL3 selective expression in airway smooth muscle (ASM) influences ASM function, we used Cre-loxP techniques to generate transgenic mice (hORMDL3Myh11eGFP-cre), which express human ORMDL3 selectively in smooth muscle cells. In vitro studies of ASM cells isolated from the bronchi of hORMDL3Myh11eGFP-cre mice demonstrated that they developed hypertrophy (quantitated by FACS and image analysis), developed hyperplasia (assessed by BrdU incorporation), and expressed increased levels of tropomysin proteins TPM1 and TPM4. siRNA knockdown of TPM1 or TPM4 demonstrated their importance to ORMDL3-mediated ASM proliferation but not hypertrophy. In addition, ASM derived from hORMDL3Myh11eGFP-cre mice had increased contractility to histamine in vitro, which was associated with increased levels of intracellular Ca2+; increased cell surface membrane Orai1 Ca2+ channels, which mediate influx of Ca2+ into the cytoplasm; and increased expression of ASM contractile genes sarco/endoplasmic reticulum Ca2+ ATPase 2b and smooth muscle 22. In vivo studies of hORMDL3Myh11eGFP-cre mice demonstrated that they had a spontaneous increase in ASM and airway hyperreactivity (AHR). ORMDL3 expression in ASM thus induces changes in ASM (hypertrophy, hyperplasia, increased contractility), which may explain the contribution of ORMDL3 to the development of AHR in childhood onset asthma, which is highly linked to ORMDL3 on chromosome 17q12-21.
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Affiliation(s)
- Alexa K. Pham
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Marina Miller
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Peter Rosenthal
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Sudipta Das
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Ning Weng
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Sunghoon Jang
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Richard C. Kurten
- Department of Pediatrics, Arkansas Children’s Research Institute, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Jana Badrani
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Taylor A. Doherty
- Department of Medicine, University of California San Diego, La Jolla, California, USA
- Veterans Affairs San Diego Health Care System, La Jolla, California, USA
| | - Brian Oliver
- School of Life Sciences, University of Technology Sydney, Sydney, Australia
| | - David H. Broide
- Department of Medicine, University of California San Diego, La Jolla, California, USA
- School of Life Sciences, University of Technology Sydney, Sydney, Australia
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6
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Wang L, Chitano P, Seow CY. Filament evanescence of myosin II and smooth muscle function. J Gen Physiol 2021; 153:211814. [PMID: 33606000 PMCID: PMC7901143 DOI: 10.1085/jgp.202012781] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 01/19/2021] [Indexed: 01/02/2023] Open
Abstract
Smooth muscle is an integral part of hollow organs. Many of them are constantly subjected to mechanical forces that alter organ shape and modify the properties of smooth muscle. To understand the molecular mechanisms underlying smooth muscle function in its dynamic mechanical environment, a new paradigm has emerged that depicts evanescence of myosin filaments as a key mechanism for the muscle’s adaptation to external forces in order to maintain optimal contractility. Unlike the bipolar myosin filaments of striated muscle, the side-polar filaments of smooth muscle appear to be less stable, capable of changing their lengths through polymerization and depolymerization (i.e., evanescence). In this review, we summarize accumulated knowledge on the structure and mechanism of filament formation of myosin II and on the influence of ionic strength, pH, ATP, myosin regulatory light chain phosphorylation, and mechanical perturbation on myosin filament stability. We discuss the scenario of intracellular pools of monomeric and filamentous myosin, length distribution of myosin filaments, and the regulatory mechanisms of filament lability in contraction and relaxation of smooth muscle. Based on recent findings, we suggest that filament evanescence is one of the fundamental mechanisms underlying smooth muscle’s ability to adapt to the external environment and maintain optimal function. Finally, we briefly discuss how increased ROCK protein expression in asthma may lead to altered myosin filament stability, which may explain the lack of deep-inspiration–induced bronchodilation and bronchoprotection in asthma.
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Affiliation(s)
- Lu Wang
- Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,The Centre for Heart Lung Innovation, University of British Columbia, Vancouver, British Columbia, Canada
| | - Pasquale Chitano
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,The Centre for Heart Lung Innovation, University of British Columbia, Vancouver, British Columbia, Canada
| | - Chun Y Seow
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,The Centre for Heart Lung Innovation, University of British Columbia, Vancouver, British Columbia, Canada
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7
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Yao YB, Xiao CF, Lu JG, Wang C. Caldesmon: Biochemical and Clinical Implications in Cancer. Front Cell Dev Biol 2021; 9:634759. [PMID: 33681215 PMCID: PMC7930484 DOI: 10.3389/fcell.2021.634759] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Accepted: 01/18/2021] [Indexed: 12/19/2022] Open
Abstract
Caldesmon, an actin-binding protein, can inhibit myosin binding to actin and regulate smooth muscle contraction and relaxation. However, caldesmon has recently attracted attention due to its importance in cancer. The upregulation of caldesmon in several solid cancer tissues has been reported. Caldesmon, as well as its two isoforms, is considered as a biomarker for cancer and a potent suppressor of cancer cell invasion by regulating podosome/invadopodium formation. Therefore, caldesmon may be a promising therapeutic target for diseases such as cancer. Here, we review new studies on the gene transcription, isoform structure, expression, and phosphorylation regulation of caldesmon and discuss its clinical implications in cancer.
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Affiliation(s)
- Yi-Bo Yao
- Department of Anorectal Surgery, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Chang-Fang Xiao
- Department of Anorectal Surgery, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Jin-Gen Lu
- Longhua Hospital, Institute of Chinese Traditional Surgery, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Chen Wang
- Department of Anorectal Surgery, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
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8
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Fisicaro N, Salvaris EJ, Philip GK, Wakefield MJ, Nottle MB, Hawthorne WJ, Cowan PJ. Fok
I‐dCas9 mediates high‐fidelity genome editing in pigs. Xenotransplantation 2019; 27:e12551. [DOI: 10.1111/xen.12551] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2019] [Revised: 07/02/2019] [Accepted: 07/24/2019] [Indexed: 12/12/2022]
Affiliation(s)
- Nella Fisicaro
- Immunology Research Centre St Vincent’s Hospital Melbourne Melbourne Vic. Australia
| | - Evelyn J. Salvaris
- Immunology Research Centre St Vincent’s Hospital Melbourne Melbourne Vic. Australia
| | - Gayle K. Philip
- Melbourne Bioinformatics University of Melbourne Melbourne Vic. Australia
| | - Matthew J. Wakefield
- Melbourne Bioinformatics University of Melbourne Melbourne Vic. Australia
- Walter and Eliza Hall Institute Melbourne Vic. Australia
| | - Mark B. Nottle
- Robinson Research Institute & Adelaide Medical School University of Adelaide Adelaide SA Australia
| | - Wayne J. Hawthorne
- Department of Surgery, Westmead Clinical School Westmead Hospital, University of Sydney Sydney NSW Australia
- The Centre for Transplant and Renal Research Westmead Institute for Medical Research Westmead NSW Australia
| | - Peter J. Cowan
- Immunology Research Centre St Vincent’s Hospital Melbourne Melbourne Vic. Australia
- Department of Medicine University of Melbourne Melbourne Vic. Australia
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9
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Takeya K, Kathol I, Sutherland C, Wang X, Loutzenhiser R, Walsh MP. Expression of troponin subunits in the rat renal afferent arteriole. IUBMB Life 2019; 71:1475-1481. [PMID: 31046198 DOI: 10.1002/iub.2061] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Revised: 04/18/2019] [Accepted: 04/21/2019] [Indexed: 11/10/2022]
Abstract
Vascular smooth muscle cells of the renal afferent arteriole are unusual in that they must be able to contract very rapidly in response to a sudden increase in systemic blood pressure in order to protect the downstream glomerular capillaries from catastrophic damage. We showed that this could be accounted for, in part, by exclusive expression, at the protein level, of the "fast" (B) isoforms of smooth muscle myosin II heavy chains in the afferent arteriole, in contrast to other vascular smooth muscle cells such as the rat aorta and efferent arteriole which express exclusively the "slow" (A) isoforms (Shiraishi et al. (2003) FASEB. J. 17, 2284-2286). As contraction of the more rapidly contracting striated (skeletal and cardiac) muscles is regulated by the thin filament-associated troponin (Tn) system, we hypothesized that Tn or a Tn-like system may exist in afferent arteriolar cells and contribute to the unusually rapid contraction of this tissue in response to increased intraluminal pressure. We examined the expression of TnC (Ca2+ -binding subunit), TnI (inhibitory subunit), and TnT (tropomyosin-binding subunit) in vascular smooth muscle cells of the rat renal afferent arteriole at the mRNA level. Fast-twitch skeletal muscle and slow-twitch skeletal muscle/cardiac TnC isoforms and slow-twitch skeletal muscle and cardiac TnI isoforms were detected by reverse transcription-polymerase chain reaction (RT-PCR) and confirmed by cDNA sequencing. Furthermore, cardiac and slow-twitch skeletal muscle TnI isoforms, but not fast-twitch skeletal muscle TnI, were detected in isolated afferent arterioles at the protein level by proximity ligation assay. Finally, striated muscle myosin II heavy chain expression was identified in isolated rat afferent arterioles by RT-PCR. We conclude that, in addition to Ca2+ -mediated phosphorylation of myosin II regulatory light chains, contraction of the afferent arteriole may be regulated by a mechanism normally associated with the much more rapidly contracting cardiac and skeletal muscles, which involves Ca2+ binding to TnC, leading to alleviation of inhibition of the actomyosin MgATPase by TnI and tropomyosin and rapid contraction of the vessel.
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Affiliation(s)
- Kosuke Takeya
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Physiology & Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Iris Kathol
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Physiology & Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Cindy Sutherland
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Xuemei Wang
- Department of Physiology & Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Rodger Loutzenhiser
- Department of Physiology & Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Michael P Walsh
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
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10
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Zhao B, Baloch Z, Ma Y, Wan Z, Huo Y, Li F, Zhao Y. Identification of Potential Key Genes and Pathways in Early-Onset Colorectal Cancer Through Bioinformatics Analysis. Cancer Control 2019; 26:1073274819831260. [PMID: 30786729 PMCID: PMC6383095 DOI: 10.1177/1073274819831260] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 10/24/2018] [Accepted: 01/23/2019] [Indexed: 12/15/2022] Open
Abstract
This study was designed to identify the potential key protein interaction networks, genes, and correlated pathways in early-onset colorectal cancer (CRC) via bioinformatics methods. We selected microarray data GSE4107 consisting 12 patient's colonic mucosa and 10 healthy control mucosa; initially, the GSE4107 were downloaded and analyzed using limma package to identify differentially expressed genes (DEGs). A total of 131 DEGs consisting of 108 upregulated genes and 23 downregulated genes of patients in early-onset CRC were selected by the criteria of adjusted P values <.01 and |log2 fold change (FC)| ≥ 2. The gene ontology functional enrichment analysis and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were accomplished to view the biological process, cellular components, molecular function, and the KEGG pathways of DEGs. Finally, protein-protein interactions (PPIs) were constructed, and the hub protein module was identified. Genes such as ACTA2, ACTG2, MYH11, CALD1, MYL9, TPM2, and LMOD1 were strongly implicated in CRC. In summary, in this study, we indicated that molecular mechanisms were involved in muscle contraction and vascular smooth muscle contraction signaling pathway, which improve our understanding of CRC and could be used as new therapeutic targets for CRC.
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Affiliation(s)
- Bin Zhao
- Medical College of Xiamen University, Xiamen, Fujian, China
| | - Zulqarnain Baloch
- College of Veterinary Medicine, South China Agricultural University,
Guangzhou, China
| | - Yunhan Ma
- Medical College of Xiamen University, Xiamen, Fujian, China
| | - Zheng Wan
- Medical College of Xiamen University, Xiamen, Fujian, China
| | - Yani Huo
- Medical College of Xiamen University, Xiamen, Fujian, China
| | - Fujun Li
- The Department of Anesthesiology, the First Affiliated Hospital of
Harbin Medical University, Harbin, Heilongjiang, China
| | - Yilin Zhao
- Medical College of Xiamen University, Xiamen, Fujian, China
- Department of Oncology and Vascular Interventional Radiology,
Zhongshan Hospital affiliated of Xiamen University, Xiamen, Fujian, China
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11
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Yabasin IB, Sanches JGP, Ibrahim MM, Huidan J, Williams W, Lu ZL, Wen Q. Cisatracurium Retards Cell Migration and Invasion Upon Upregulation of p53 and Inhibits the Aggressiveness of Colorectal Cancer. Front Physiol 2018; 9:941. [PMID: 30108509 PMCID: PMC6079220 DOI: 10.3389/fphys.2018.00941] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 06/26/2018] [Indexed: 12/12/2022] Open
Abstract
Colorectal cancer (CRC) is reported to be the third and fourth, most diagnosed and cause of cancer associated deaths respectively. In 2012 for instance, about 1.4 million new cases were reported, and approximately 700,000 deaths recorded. Survival from CRC is dependent on the stage at which it is diagnosed coupled with appropriate surgical and medical intervention. Cisatracurium is widely used for skeletal muscle relaxation during abdominal surgeries, including bowel and colon surgeries. Recent studies reported that cisatracurium inhibits progression of human cancer cells, however, the mechanisms leading to the inhibition are yet to be completely understood. To elucidate mechanisms resulting particularly in tumor cell growth and metastasis, we developed ex vivo and in in vivo xenograft models of CRC. Cisatracurium caused upregulation of p53 and its down-stream genes and proteins known to regulate proliferation and metastasis in vitro and in vivo. Genomic analyses of CRC following cisatracurium treatment revealed moderate to high DNA damage, while functional analyses demonstrated significant tumor cells growth regression, as well as repression of migration and invasion. Importantly, cisatracurium increased E-Cadherin and CALD-1 but decreased SNAI-1 and SLUG levels in vitro and in vivo. Together, the findings demonstrate that elevation of p53 upon cisatracurium-induced genomic injury, represent a potential mechanism by which cisatracurium result in the suppression of CRC progression and metastasis.
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Affiliation(s)
- Iddrisu B Yabasin
- Department of Anesthesiology, First Affiliated Hospital of Dalian Medical University, Dalian, China
| | | | - Mohammed M Ibrahim
- Department of Pathology and Forensics, Dalian Medical University, Dalian, China
| | - Jin Huidan
- Department of Anesthesiology, First Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Walana Williams
- Department of Microbiology and Immunology, Dalian Medical University, Dalian, China
| | - Zhi-Li Lu
- Department of Ophthalmology, First Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Qingping Wen
- Department of Anesthesiology, First Affiliated Hospital of Dalian Medical University, Dalian, China
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12
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Shim JE, Bang C, Yang S, Lee T, Hwang S, Kim CY, Singh-Blom UM, Marcotte EM, Lee I. GWAB: a web server for the network-based boosting of human genome-wide association data. Nucleic Acids Res 2017; 45:W154-W161. [PMID: 28449091 PMCID: PMC5793838 DOI: 10.1093/nar/gkx284] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2017] [Revised: 04/01/2017] [Accepted: 04/17/2017] [Indexed: 12/29/2022] Open
Abstract
During the last decade, genome-wide association studies (GWAS) have represented a major approach to dissect complex human genetic diseases. Due in part to limited statistical power, most studies identify only small numbers of candidate genes that pass the conventional significance thresholds (e.g. P ≤ 5 × 10-8). This limitation can be partly overcome by increasing the sample size, but this comes at a higher cost. Alternatively, weak association signals can be boosted by incorporating independent data. Previously, we demonstrated the feasibility of boosting GWAS disease associations using gene networks. Here, we present a web server, GWAB (www.inetbio.org/gwab), for the network-based boosting of human GWAS data. Using GWAS summary statistics (P-values) for SNPs along with reference genes for a disease of interest, GWAB reprioritizes candidate disease genes by integrating the GWAS and network data. We found that GWAB could more effectively retrieve disease-associated reference genes than GWAS could alone. As an example, we describe GWAB-boosted candidate genes for coronary artery disease and supporting data in the literature. These results highlight the inherent value in sub-threshold GWAS associations, which are often not publicly released. GWAB offers a feasible general approach to boost such associations for human disease genetics.
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Affiliation(s)
- Jung Eun Shim
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Korea
| | - Changbae Bang
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Korea
| | - Sunmo Yang
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Korea
| | - Tak Lee
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Korea
| | - Sohyun Hwang
- Department of Biomedical Science, College of Life Science, CHA University, Seongnam-si 13496, Korea
| | - Chan Yeong Kim
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Korea
| | - U Martin Singh-Blom
- Cognition Group, Schibsted Products & Technologies, Västra Järnvägsgatan 21, 111 64 Stockholm, Sweden
| | - Edward M Marcotte
- Center for Systems and Synthetic Biology, Institute for Cellular and Molecular Biology, University of Texas, Austin, TX 78712, USA
- Department of Molecular Biosciences, University of Texas at Austin, TX 78712, USA
| | - Insuk Lee
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Korea
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13
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Ets HK, Seow CY, Moreland RS. Sustained Contraction in Vascular Smooth Muscle by Activation of L-type Ca 2+ Channels Does Not Involve Ca 2+ Sensitization or Caldesmon. Front Pharmacol 2017; 7:516. [PMID: 28082901 PMCID: PMC5183594 DOI: 10.3389/fphar.2016.00516] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 12/12/2016] [Indexed: 11/13/2022] Open
Abstract
Vascular smooth muscle (VSM) is unique in its ability to maintain an intrinsic level of contractile force, known as tone. Vascular tone is believed to arise from the constitutive activity of membrane-bound L-type Ca2+ channels (LTCC). This study used a pharmacological agonist of LTCC, Bay K8644, to elicit a sustained, sub-maximal contraction in VSM that mimics tone. Downstream signaling was investigated in order to determine what molecules are responsible for tone. Medial strips of swine carotid artery were stimulated with 100 nM Bay K8644 to induce a sustained level of force. Force and phosphorylation levels of myosin light chain (MLC), MAP kinase, MYPT1, CPI-17, and caldesmon were measured during Bay K8644 stimulation in the presence and absence of nifedipine, ML-7, U0126, bisindolylmaleimide (Bis), and H-1152. Nifedipine and ML-7 inhibited force and MLC phosphorylation in response to Bay K8644. Inhibition of Rho kinase (H-1152) but not PKC (Bis) inhibited Bay K8644 induced force. U0126 significantly increased Bay K8644-dependent force with no effect on MLC phosphorylation. Neither CPI-17 nor caldesmon phosphorylation were increased during the maintenance of sustained force. Our results suggest that force due to the influx of calcium through LTCCs is partially MLC phosphorylation-dependent but does not involve PKC or caldesmon. Interestingly, inhibition of MLC kinase (MLCK) and PKC significantly increased MAP kinase phosphorylation suggesting that MLCK and PKC may directly or indirectly inhibit MAP kinase activity during prolonged contractions induced by Bay K8544.
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Affiliation(s)
- Hillevi K Ets
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia PA, USA
| | - Chun Y Seow
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver BC, Canada
| | - Robert S Moreland
- Department of Pharmacology and Physiology, Drexel University College of Medicine, PhiladelphiaPA, USA; Department of Pathology and Laboratory Medicine, Drexel University College of Medicine, PhiladelphiaPA, USA
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14
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Barnes DE, Hwang H, Ono K, Lu H, Ono S. Molecular evolution of troponin I and a role of its N-terminal extension in nematode locomotion. Cytoskeleton (Hoboken) 2016; 73:117-30. [PMID: 26849746 DOI: 10.1002/cm.21281] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Revised: 01/22/2016] [Accepted: 01/27/2016] [Indexed: 01/29/2023]
Abstract
The troponin complex, composed of troponin T (TnT), troponin I (TnI), and troponin C (TnC), is the major calcium-dependent regulator of muscle contraction, which is present widely in both vertebrates and invertebrates. Little is known about evolutionary aspects of troponin in the animal kingdom. Using a combination of data mining and functional analysis of TnI, we report evidence that an N-terminal extension of TnI is present in most of bilaterian animals as a functionally important domain. Troponin components have been reported in species in most of representative bilaterian phyla. Comparison of TnI sequences shows that the core domains are conserved in all examined TnIs, and that N- and C-terminal extensions are variable among isoforms and species. In particular, N-terminal extensions are present in all protostome TnIs and chordate cardiac TnIs but lost in a subset of chordate TnIs including vertebrate skeletal-muscle isoforms. Transgenic rescue experiments in Caenorhabditis elegans striated muscle show that the N-terminal extension of TnI (UNC-27) is required for coordinated worm locomotion but not in sarcomere assembly and single muscle-contractility kinetics. These results suggest that N-terminal extensions of TnIs are retained from a TnI ancestor as a functional domain.
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Affiliation(s)
- Dawn E Barnes
- Department of Pathology and Department of Cell Biology, Emory University, Atlanta, Georgia
| | - Hyundoo Hwang
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia.,School of Engineering and Sciences, Technológico de Monterrey, Monterrey, Nuevo León, Mexico
| | - Kanako Ono
- Department of Pathology and Department of Cell Biology, Emory University, Atlanta, Georgia
| | - Hang Lu
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia.,Interdisciplinary Program of Bioengineering, Georgia Institute of Technology, Atlanta, Georgia.,The Petit Institute for Bioengineering and Biosciences, Georgia Institute of Technology, Atlanta, Georgia
| | - Shoichiro Ono
- Department of Pathology and Department of Cell Biology, Emory University, Atlanta, Georgia
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15
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Abstract
Vascular smooth muscle (VSM; see Table 1 for a list of abbreviations) is a heterogeneous biomaterial comprised of cells and extracellular matrix. By surrounding tubes of endothelial cells, VSM forms a regulated network, the vasculature, through which oxygenated blood supplies specialized organs, permitting the development of large multicellular organisms. VSM cells, the engine of the vasculature, house a set of regulated nanomotors that permit rapid stress-development, sustained stress-maintenance and vessel constriction. Viscoelastic materials within, surrounding and attached to VSM cells, comprised largely of polymeric proteins with complex mechanical characteristics, assist the engine with countering loads imposed by the heart pump, and with control of relengthening after constriction. The complexity of this smart material can be reduced by classical mechanical studies combined with circuit modeling using spring and dashpot elements. Evaluation of the mechanical characteristics of VSM requires a more complete understanding of the mechanics and regulation of its biochemical parts, and ultimately, an understanding of how these parts work together to form the machinery of the vascular tree. Current molecular studies provide detailed mechanical data about single polymeric molecules, revealing viscoelasticity and plasticity at the protein domain level, the unique biological slip-catch bond, and a regulated two-step actomyosin power stroke. At the tissue level, new insight into acutely dynamic stress-strain behavior reveals smooth muscle to exhibit adaptive plasticity. At its core, physiology aims to describe the complex interactions of molecular systems, clarifying structure-function relationships and regulation of biological machines. The intent of this review is to provide a comprehensive presentation of one biomachine, VSM.
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Affiliation(s)
- Paul H Ratz
- Department of Biochemistry and Molecular Biology, Virginia Commonwealth University, Richmond, Virginia, USA
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16
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Bisht S, Nolting J, Schütte U, Haarmann J, Jain P, Shah D, Brossart P, Flaherty P, Feldmann G. Cyclin-Dependent Kinase 5 (CDK5) Controls Melanoma Cell Motility, Invasiveness, and Metastatic Spread-Identification of a Promising Novel therapeutic target. Transl Oncol 2015; 8:295-307. [PMID: 26310376 PMCID: PMC4562979 DOI: 10.1016/j.tranon.2015.06.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2015] [Revised: 06/16/2015] [Accepted: 06/23/2015] [Indexed: 01/03/2023] Open
Abstract
Despite considerable progress in recent years, the overall prognosis of metastatic malignant melanoma remains poor, and curative therapeutic options are lacking. Therefore, better understanding of molecular mechanisms underlying melanoma progression and metastasis, as well as identification of novel therapeutic targets that allow inhibition of metastatic spread, are urgently required. The current study provides evidence for aberrant cyclin-dependent kinase 5 (CDK5) activation in primary and metastatic melanoma lesions by overexpression of its activator protein CDK5R1/p35. Moreover, using melanoma in vitro model systems, shRNA-mediated inducible knockdown of CDK5 was found to cause marked inhibition of cell motility, invasiveness, and anchorage-independent growth, while at the same time net cell growth was not affected. In vivo, CDK5 knockdown inhibited growth of orthotopic xenografts as well as formation of lung and liver colonies in xenogenic injection models mimicking systemic metastases. Inhibition of lung metastasis was further validated in a syngenic murine melanoma model. CDK5 knockdown was accompanied by dephosphorylation and overexpression of caldesmon, and concomitant caldesmon knockdown rescued cell motility and proinvasive phenotype. Finally, it was found that pharmacological inhibition of CDK5 activity by means of roscovitine as well as by a novel small molecule CDK5-inhibitor, N-(5-isopropylthiazol-2-yl)-3-phenylpropanamide, similarly caused marked inhibition of invasion/migration, colony formation, and anchorage-independent growth of melanoma cells. Thus, experimental data presented here provide strong evidence for a crucial role of aberrantly activated CDK5 in melanoma progression and metastasis and establish CDK5 as promising target for therapeutic intervention.
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Affiliation(s)
- Savita Bisht
- Department of Internal Medicine 3, Center of Integrated Oncology (CIO) Cologne-Bonn, University Hospital of Bonn, Germany
| | - Jens Nolting
- Department of Internal Medicine 3, Center of Integrated Oncology (CIO) Cologne-Bonn, University Hospital of Bonn, Germany
| | - Ute Schütte
- Department of Internal Medicine 3, Center of Integrated Oncology (CIO) Cologne-Bonn, University Hospital of Bonn, Germany
| | - Jens Haarmann
- Department of Internal Medicine 3, Center of Integrated Oncology (CIO) Cologne-Bonn, University Hospital of Bonn, Germany
| | - Prashi Jain
- Mylan School of Pharmacy, Medicinal Chemistry, Duquesne University, Pittsburgh, PA
| | - Dhruv Shah
- Mylan School of Pharmacy, Medicinal Chemistry, Duquesne University, Pittsburgh, PA
| | - Peter Brossart
- Department of Internal Medicine 3, Center of Integrated Oncology (CIO) Cologne-Bonn, University Hospital of Bonn, Germany
| | - Patrick Flaherty
- Mylan School of Pharmacy, Medicinal Chemistry, Duquesne University, Pittsburgh, PA
| | - Georg Feldmann
- Department of Internal Medicine 3, Center of Integrated Oncology (CIO) Cologne-Bonn, University Hospital of Bonn, Germany.
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17
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Kim HR, Gallant C, Morgan KG. Regulation of PKC autophosphorylation by calponin in contractile vascular smooth muscle tissue. BIOMED RESEARCH INTERNATIONAL 2013; 2013:358643. [PMID: 24350264 PMCID: PMC3852320 DOI: 10.1155/2013/358643] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Revised: 10/10/2013] [Accepted: 10/24/2013] [Indexed: 01/31/2023]
Abstract
Protein kinase C (PKC) is a key enzyme involved in agonist-induced smooth muscle contraction. In some cases, regulatory phosphorylation of PKC is required for full activation of the enzyme. However, this issue has largely been ignored with respect to PKC-dependent regulation of contractile vascular smooth muscle (VSM) contractility. The first event in PKC regulation is a transphosphorylation by PDK at a conserved threonine in the activation loop of PKC, followed by the subsequent autophosphorylation at the turn motif and hydrophobic motif sites. In the present study, we determined whether phosphorylation of PKC is a regulated process in VSM and also investigated a potential role of calponin in the regulation of PKC. We found that calponin increases the level of in vitro PKCα phosphorylation at the PDK and hydrophobic sites, but not the turn motif site. In vascular tissues, phosphorylation of the PKC hydrophobic site, but not turn motif site, as well as phosphorylation of PDK at S241 increased in response to phenylephrine. Calponin knockdown inhibits autophosphorylation of cellular PKC in response to phenylephrine, confirming results with recombinant PKC. Thus these results show that autophosphorylation of PKC is regulated in dVSM and calponin is necessary for autophosphorylation of PKC in VSM.
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Affiliation(s)
- Hak Rim Kim
- Department of Health Sciences, Boston University, 635 Commonwealth Avenue, Boston, MA 02215, USA
- Department of Pharmacology, College of Medicine, Dankook University, 119 Dandaero, Chungnam, Cheonan-si 330-714, Republic of Korea
| | - Cynthia Gallant
- Department of Health Sciences, Boston University, 635 Commonwealth Avenue, Boston, MA 02215, USA
| | - Kathleen G. Morgan
- Department of Health Sciences, Boston University, 635 Commonwealth Avenue, Boston, MA 02215, USA
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18
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Deng M, Boopathi E, Hypolite JA, Raabe T, Chang S, Zderic S, Wein AJ, Chacko S. Amino acid mutations in the caldesmon COOH-terminal functional domain increase force generation in bladder smooth muscle. Am J Physiol Renal Physiol 2013; 305:F1455-65. [PMID: 23986516 DOI: 10.1152/ajprenal.00174.2013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Caldesmon (CaD), a component of smooth muscle thin filaments, binds actin, tropomyosin, calmodulin, and myosin and inhibits actin-activated ATP hydrolysis by smooth muscle myosin. Internal deletions of the chicken CaD functional domain that spans from amino acids (aa) 718 to 731, which corresponds to aa 512-530 including the adjacent aa sequence in mouse CaD, lead to diminished CaD-induced inhibition of actin-activated ATP hydrolysis by myosin. Transgenic mice with mutations of five aa residues (Lys(523) to Gln, Val(524) to Leu, Ser(526) to Thr, Pro(527) to Cys, and Lys(529) to Ser), which encompass the ATPase inhibitory determinants located in exon 12, were generated by homologous recombination. Homozygous (-/-) animals did not develop, but heterozygous (+/-) mice carrying the expected mutations in the CaD ATPase inhibitory domain (CaD mutant) matured and reproduced normally. The peak force produced in response to KCl and electrical field stimulation by the detrusor smooth muscle from the CaD mutant was high compared with that of the wild type. CaD mutant mice revealed nonvoiding contractions during bladder filling on awake cystometry, suggesting that the CaD ATPase inhibitory domain suppresses force generation during the filling phase and this suppression is partially released by mutations in 50% of CaD in heterozygous. Our data show for the first time a functional phenotype, at the intact smooth muscle tissue and in vivo organ levels, following mutation of a functional domain at the COOH-terminal region of CaD.
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Affiliation(s)
- Maoxian Deng
- Dept. of Surgery and Dept. of Pathobiology, Univ. of Pennsylvania, 500 South Ridgeway Ave., Glenolden, PA 19036.
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19
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Value of PAX8, PAX2, claudin-4, and h-caldesmon immunostaining in distinguishing peritoneal epithelioid mesotheliomas from serous carcinomas. Mod Pathol 2013; 26:553-62. [PMID: 23196794 DOI: 10.1038/modpathol.2012.200] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Distinguishing between peritoneal epithelioid mesotheliomas and papillary serous carcinomas involving the peritoneum can be difficult on routine histological preparations, but this differential diagnosis can be facilitated by the use of immunohistochemistry. Recent investigations have indicated that PAX8, PAX2, claudin-4, and h-caldesmon are immunohistochemical markers that can assist in distinguishing between these two malignancies; however, much of the information published on the value of these markers is either insufficient or contradictory. The purpose of this study is to resolve some of the existing controversies and to fully determine the practical value of these markers for assisting in the differential diagnosis between peritoneal mesotheliomas and serous carcinomas. In order to do so, a total of 40 peritoneal epithelioid mesotheliomas and 45 serous carcinomas (15 primary, 30 metastatic to the peritoneum) were investigated. PAX8 and PAX2 nuclear positivity was demonstrated in 42 (93%) and 25 (56%) of the serous carcinomas, respectively, whereas none of the mesotheliomas expressed either marker. Forty-four (98%) of the serous carcinomas exhibited claudin-4 reactivity along the cell membrane, whereas none of the mesotheliomas were positive for this marker. All of the serous carcinomas and mesotheliomas were negative for h-caldesmon. Based on these results, it is concluded that PAX8 and claudin-4 have a higher sensitivity and specificity for assisting in discriminating between peritoneal epithelioid mesotheliomas and serous carcinomas when compared with all of the other positive carcinoma markers that are, at present, recommended to be included in the immunohistochemical panels used in this differential diagnosis. Even though it is highly specific, PAX2 has little practical value in the diagnosis of peritoneal epithelioid mesotheliomas as its sensitivity is low. The h-caldesmon is not useful.
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20
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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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21
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Guo H, Huang R, Semba S, Kordowska J, Huh YH, Khalina-Stackpole Y, Mabuchi K, Kitazawa T, Wang CLA. Ablation of smooth muscle caldesmon affects the relaxation kinetics of arterial muscle. Pflugers Arch 2012; 465:283-94. [PMID: 23149489 DOI: 10.1007/s00424-012-1178-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2012] [Revised: 10/26/2012] [Accepted: 10/30/2012] [Indexed: 01/04/2023]
Abstract
Smooth muscle caldesmon (h-CaD) is an actin- and myosin-binding protein that reversibly inhibits the actomyosin ATPase activity in vitro. To test the function of h-CaD in vivo, we eliminated its expression in mice. The h-CaD-null animals appeared normal and fertile, although the litter size was smaller. Tissues from the homozygotes lacked h-CaD and exhibited upregulation of the non-muscle isoform, l-CaD, in visceral, but not vascular tonic smooth muscles. While the Ca(2+) sensitivity of force generation of h-CaD-deficient smooth muscle remained largely unchanged, the kinetic behavior during relaxation in arteries was different. Both intact and permeabilized arterial smooth muscle tissues from the knockout animals relaxed more slowly than those of the wild type. Since this difference occurred after myosin dephosphorylation was complete, the kinetic effect most likely resulted from slower detachment of unphosphorylated crossbridges. Detailed analyses revealed that the apparently slower relaxation of h-CaD-null smooth muscle was due to an increase in the amplitude of a slower component of the biphasic tension decay. While the identity of this slower process has not been unequivocally determined, we propose it reflects a thin filament state that elicits fewer re-attached crossbridges. Our finding that h-CaD modulates the rate of smooth muscle relaxation clearly supports a role in the control of vascular tone.
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Affiliation(s)
- Hongqiu Guo
- Boston Biomedical Research Institute, Watertown, MA, 02472, USA
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22
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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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23
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Quintavalle M, Elia L, Price JH, Heynen-Genel S, Courtneidge SA. A cell-based high-content screening assay reveals activators and inhibitors of cancer cell invasion. Sci Signal 2011; 4:ra49. [PMID: 21791703 DOI: 10.1126/scisignal.2002032] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Acquisition of invasive cell behavior underlies tumor progression and metastasis. To further define the molecular mechanisms underlying invasive behavior, we developed a high-throughput screening strategy to quantitate invadopodia, which are actin-rich membrane protrusions of cancer cells that contribute to tissue invasion and matrix remodeling. We tested the LOPAC 1280 collection of pharmacologically active agents in a high-content, image-based assay and identified compounds that inhibited invadopodium formation without overt toxicity, as well as compounds that increased invadopodia number. The chemotherapeutic agent paclitaxel increased both the number of invadopodia and the invasive behavior of various human cancer cell lines, effects that have potential clinical implications for its use before surgical removal of a primary tumor (neoadjuvant therapy) or in patients with chemoresistant tumors. Several compounds that inhibited invasion have been characterized as cyclin-dependent kinase (Cdk) inhibitors, and loss-of-function experiments determined that Cdk5 was the relevant target. We further determined that Cdk5 promoted both invadopodium formation and cancer cell invasion by phosphorylating and thus decreasing the abundance of the actin regulatory protein caldesmon.
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Affiliation(s)
- Manuela Quintavalle
- Sanford-Burnham Medical Research Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA
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Sobieszek A, Sarg B, Lindner H, Seow CY. Phosphorylation of caldesmon by myosin light chain kinase increases its binding affinity for phosphorylated myosin filaments. Biol Chem 2010; 391:1091-104. [DOI: 10.1515/bc.2010.105] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Abstract
Phosphorylation of myosin by myosin light chain kinase (MLCK) is essential for smooth muscle contraction. In this study we show that caldesmon (CaD) is also phosphorylated in vitro by MLCK. The phosphorylation is calcium- and calmodulin (CaM)-dependent and requires a MLCK concentration close to that found in vivo. On average, approximately 2 mol P
i
per mol of CaD are incorporated at Thr-626 and Thr-693, with additional partial phosphorylation at Ser-658 and Ser-702. The phosphorylation rate for CaD is 20- to 50-fold slower than that for filamentous myosin; faster relative rates were obtained with CaD added to purified actomyosin or myosin preparations containing endogenous MLCK/CaM complex. Addition of CaM also augmented CaD phosphorylation. We further demonstrate that [32P] labeled CaD binds much more readily to phosphorylated filamentous myosin than to unphosphorylated myosin. For actomyosin, CaD binding affinity doubles after myosin phosphorylation, without a significant change in binding stoichiometry (approx. one CaD per myosin molecule). Unphosphorylated CaD is ineffective in competing with the phosphorylated protein for the binding site(s) on myosin filaments. The ATPase activity of reconstituted actomyosin is inhibited by unphosphorylated CaD, and this inhibition was removed by CaD phosphorylation. Our results suggest that CaD phosphorylation plays a role in modifying actomyosin interaction in vivo, particularly during prolonged muscle activation.
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25
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JIANG QF, CAI SX, YAN XQ. The Effect of Caldesmon Phosphorylation on Metastatic Tumor Cell Mobility*. PROG BIOCHEM BIOPHYS 2010. [DOI: 10.3724/sp.j.1206.2009.00545] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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26
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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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Huang R, Grabarek Z, Wang CLA. Differential effects of caldesmon on the intermediate conformational states of polymerizing actin. J Biol Chem 2009; 285:71-9. [PMID: 19889635 DOI: 10.1074/jbc.m109.065078] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
The actin-binding protein caldesmon (CaD) reversibly inhibits smooth muscle contraction. In non-muscle cells, a shorter CaD isoform co-exists with microfilaments in the stress fibers at the quiescent state, but the phosphorylated CaD is found at the leading edge of migrating cells where dynamic actin filament remodeling occurs. We have studied the effect of a C-terminal fragment of CaD (H32K) on the kinetics of the in vitro actin polymerization by monitoring the fluorescence of pyrene-labeled actin. Addition of H32K or its phosphorylated form either attenuated or accelerated the pyrene emission enhancement, depending on whether it was added at the early or the late phase of actin polymerization. However, the CaD fragment had no effect on the yield of sedimentable actin, nor did it affect the actin ATPase activity. Our findings can be explained by a model in which nascent actin filaments undergo a maturation process that involves at least two intermediate conformational states. If present at early stages of actin polymerization, CaD stabilizes one of the intermediate states and blocks the subsequent filament maturation. Addition of CaD at a later phase accelerates F-actin formation. The fact that CaD is capable of inhibiting actin filament maturation provides a novel function for CaD and suggests an active role in the dynamic reorganization of the actin cytoskeleton.
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Affiliation(s)
- Renjian Huang
- Boston Biomedical Research Institute, Watertown, Massachusetts 02472, USA
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Smolock EM, Trappanese DM, Chang S, Wang T, Titchenell P, Moreland RS. siRNA-mediated knockdown of h-caldesmon in vascular smooth muscle. Am J Physiol Heart Circ Physiol 2009; 297:H1930-9. [PMID: 19767533 PMCID: PMC2781382 DOI: 10.1152/ajpheart.00129.2009] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2009] [Accepted: 09/15/2009] [Indexed: 01/13/2023]
Abstract
Smooth muscle contraction involves phosphorylation of the regulatory myosin light chain. However, this thick-filament system of regulation cannot account for all aspects of a smooth muscle contraction. An alternate site of contractile regulation may be in the thin-filament-associated proteins, in particular caldesmon. Caldesmon has been proposed to be an inhibitory protein that acts either as a brake to stop any increase in resting or basal tone, or as a modulatory protein during contraction. The goal of this study was to use short interfering RNA technology to decrease the levels of the smooth muscle-specific isoform of caldesmon in intact vascular smooth muscle tissue to determine more carefully what role(s) caldesmon has in smooth muscle regulation. Intact strips of vascular tissue depleted of caldesmon produced significant levels of shortening velocity, indicative of cross-bridge cycling, in the unstimulated tissue and exhibited lower levels of contractile force to histamine. Our results also suggest that caldesmon does not play a role in the cooperative activation of unphosphorylated cross bridges by phosphorylated cross bridges. The velocity of shortening of the constitutively active tissue and the high basal values of myosin light chain phosphorylation suggest that h-caldesmon in vivo acts as a brake against contractions due to basally phosphorylated myosin. It is also possible that phosphorylation of h-caldesmon alone in the resting state may be a mechanism to produce increases in force without stimulation and increases in calcium. Disinhibition of h-caldesmon by phosphorylation would then allow force to be developed by activated myosin in the resting state.
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Affiliation(s)
- Elaine M Smolock
- Department of Pharmacology and Physiology, Drexel University College of Medicine, 245 N. 15th St., MS #488, Philadelphia, PA 19102, USA
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Kulikova N, Avrova SV, Borovikov YS. Caldesmon inhibits the rotation of smooth actin subdomain-1 and alters its mobility during the ATP hydrolysis cycle. Biochem Biophys Res Commun 2009; 390:125-9. [PMID: 19782047 DOI: 10.1016/j.bbrc.2009.09.079] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2009] [Accepted: 09/21/2009] [Indexed: 10/25/2022]
Abstract
Smooth muscle thin filaments have been reconstituted in muscle ghost fibers by incorporation of smooth muscle actin, tropomyosin and caldesmon. For the first time, rotation of subdomain-1 and changes of its mobility in IAEDANS-labeled actin during the ATP hydrolysis cycle simulated using nucleotides and non-hydrolysable ATP analogs have been demonstrated directly. Binding of caldesmon altered the mobility and inhibited the rotation of actin subdomain-1 during the transition from AM * *.ADP.Pi to AM state, resulting in inhibition of both strong and weak-binding intermediate states. These new results imply that regulation of actomyosin interaction by caldesmon during the ATPase cycle is fulfilled via the inhibition of actin subdomain-1 rotation toward the periphery of the thin filament, which decreases the area of the specific binding between actin and myosin molecules and is likely to underlie at least in part the mechanism of caldesmon-induced contractility suppression.
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Affiliation(s)
- Natalia Kulikova
- Nencki Institute of Experimental Biology, 02-093 Warsaw, Poland.
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Liou YM, Watanabe M, Yumoto M, Ishiwata S. Regulatory mechanism of smooth muscle contraction studied with gelsolin-treated strips of taenia caeci in guinea pig. Am J Physiol Cell Physiol 2009; 296:C1024-33. [DOI: 10.1152/ajpcell.00565.2008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The potential roles of the regulatory proteins actin, tropomyosin (Tm), and caldesmon (CaD), i.e., the components of the thin filament, in smooth muscle have been extensively studied in several types of smooth muscles. However, controversy remains on the putative physiological significance of these proteins. In this study, we intended to determine the functional roles of Tm and CaD in the regulation of smooth muscle contraction by using a reconstitution system of the thin filaments. At appropriate conditions, the thin (actin) filaments within skinned smooth muscle strips of taenia caeci in guinea pigs could be selectively removed by an actin-severing protein, gelsolin, without irreversible damage to the contractile apparatus, and then the thin filaments were reconstituted with purified components of thin filaments, i.e., actin, Tm, and CaD. We found that the structural remodeling of actin filaments or thin filaments was functionally linked to the Ca2+-induced force development and reduction in muscle cross-sectional area (CSA). That is, after the reconstitution of the gelsolin-treated skinned smooth muscle strips with pure actin, the Ca2+-dependent force development was partially restored, but the Ca2+-induced reduction in CSA occurred once. In contrast, the reconstitution with actin, followed by Tm and CaD, restored not only the force generation but also both its Ca2+sensitivity and the reversible Ca2+-dependent reduction in CSA. We confirmed that both removal of the thin filaments by gelsolin treatment and reconstitution of the actin (thin) filaments with Tm and CaD caused no significant changes in the level of myosin regulatory light chain phosphorylation. We thus conclude that Tm and CaD are necessary for the full regulation of smooth muscle contraction in addition to the other regulatory systems, including the myosin-linked one.
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Lin JJ, Li Y, Eppinga RD, Wang Q, Jin J. Chapter 1 Roles of Caldesmon in Cell Motility and Actin Cytoskeleton Remodeling. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2009; 274:1-68. [DOI: 10.1016/s1937-6448(08)02001-7] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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Aga M, Bradley JM, Keller KE, Kelley MJ, Acott TS. Specialized podosome- or invadopodia-like structures (PILS) for focal trabecular meshwork extracellular matrix turnover. Invest Ophthalmol Vis Sci 2008; 49:5353-65. [PMID: 18641286 DOI: 10.1167/iovs.07-1666] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
PURPOSE There are distinctive areas of colocalization of matrix metalloproteinase (MMP)-2 and -14 on trabecular meshwork (TM) cells that resemble podosomes or invadopodia. Studies were conducted to determine whether TM cells exhibit podosome- or invadopodia-like structures (PILS) and whether they produce focal extracellular matrix (ECM) turnover. METHODS Porcine and human TM cells and perfused anterior segment organ cultures were studied. Localization of PILS components on TM cells and in sections from anterior segments was determined by immunohistochemistry and confocal microscopy. Cells were grown on type I collagen labeled with fluorescein isothiocyanate (FITC) for degradation analysis. Confocal time lapse images were taken of labeled TM cells on FITC-collagen. RESULTS Immunostaining for MMP-2, MMP-14, and the typical PILS components cortactin, caldesmon, alpha-actinin, N-WASP, Arp-3, and cdc42 colocalized on these distinctive structures. Integrin-alphaV and -beta1, fibronectin, and versican colocalized with PILS components. TM cells on FITC-conjugated collagen developed focal regions of degradation. Time-lapse imaging showed dramatic and controlled movement of TM cell processes during this ECM degradation and fragment internalization. MMP-2, MMP-14, and cortactin colocalized at regions that appear to be PILS on cells within the outflow pathway in sections of human anterior segments. CONCLUSIONS TM cells exhibit areas where PILS components colocalize with MMP-2 and -14. Similar structures are found in sections, suggesting that PILS occur in situ in the outflow pathway. The collagen degradation suggests that PILS may serve as focal sites for targeted ECM turnover, an event linked to modifications of aqueous outflow resistance and intraocular pressure homeostasis.
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Affiliation(s)
- Mini Aga
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon 97239-4197, USA
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Czuryło EA, Kulikova N, Sobota A. Disturbance of smooth muscle regulatory function by Eisenia foetida toxin lysenin: Insight into the mechanism of smooth muscle contraction. Toxicon 2008; 51:1090-102. [DOI: 10.1016/j.toxicon.2008.01.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2007] [Revised: 01/04/2008] [Accepted: 01/28/2008] [Indexed: 01/25/2023]
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Deng M, Mohanan S, Polyak E, Chacko S. Caldesmon is necessary for maintaining the actin and intermediate filaments in cultured bladder smooth muscle cells. ACTA ACUST UNITED AC 2008; 64:951-65. [PMID: 17868135 DOI: 10.1002/cm.20236] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Caldesmon (CaD), a component of microfilaments in all cells and thin filaments in smooth muscle cells, is known to bind to actin, tropomyosin, calmodulin, and myosin and to inhibit actin-activated ATP hydrolysis by smooth muscle myosin. Thus, it is believed to regulate smooth muscle contraction, cell motility and the cytoskeletal structure. Using bladder smooth muscle cell cultures and RNA interference (RNAi) technique, we show that the organization of actin into microfilaments in the cytoskeleton is diminished by siRNA-mediated CaD silencing. CaD silencing significantly decreased the amount of polymerized actin (F-actin), but the expression of actin was not altered. Additionally, we find that CaD is associated with 10 nm intermediate-sized filaments (IF) and in vitro binding assay reveals that it binds to vimentin and desmin proteins. Assembly of vimentin and desmin into IF is also affected by CaD silencing, although their expression is not significantly altered when CaD is silenced. Electronmicroscopic analyses of the siRNA-treated cells showed the presence of myosin filaments and a few surrounding actin filaments, but the distribution of microfilament bundles was sparse. Interestingly, the decrease in CaD expression had no effect on tubulin expression and distribution of microtubules in these cells. These results demonstrate that CaD is necessary for the maintenance of actin microfilaments and intermediate-sized filaments in the cytoskeletal structure. This finding raises the possibility that the cytoskeletal structure in smooth muscle is affected when CaD expression is altered, as in smooth muscle de-differentiation and hypertrophy seen in certain pathological conditions.
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Affiliation(s)
- Maoxian Deng
- Division of Urology, Department of Surgery, University of Pennsylvania, Glenolden, Pennsylvania 19036, USA
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35
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Tropomyosin Gene Expression in Vivo and in Vitro. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2008. [DOI: 10.1007/978-0-387-85766-4_4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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36
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Wang CLA. Caldesmon and the regulation of cytoskeletal functions. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2008; 644:250-72. [PMID: 19209827 DOI: 10.1007/978-0-387-85766-4_19] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Caldesmon (CaD) is an extraordinary actin-binding protein, because in addition to actin, it also bindsmyosin, calmodulin and tropomyosin. As a component of the smoothmuscle and nonmuscle contractile apparatus CaD inhibits the actomyosin ATPase activity and its inhibitory action is modulated by both Ca2+ and phosphorylation. The multiplicity of binding partners and diverse biochemical properties suggest CaD is a potent and versatile regulatory protein both in contractility and cell motility. However, after decades ofinvestigation in numerous laboratories, hard evidence is still lacking to unequivocally identify its in vivo functions, although indirect evidence is mounting to support an important role in connection with the actin cytoskeleton. This chapter reviews the highlights of the past findings and summarizes the current views on this protein, with emphasis of its interaction with tropomyosin.
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Affiliation(s)
- C L Albert Wang
- Boston Biomedical Research Institute, 64 Grove Street, Watertown, MA 02472, USA.
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37
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Hitchcock-DeGregori SE, Greenfield NJ, Singh A. Tropomyosin: regulator of actin filaments. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2007; 592:87-97. [PMID: 17278358 DOI: 10.1007/978-4-431-38453-3_9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Affiliation(s)
- Sarah E Hitchcock-DeGregori
- Department of Neuroscience and Cell Biology, Robert Wood Johnson Medical School, Piscataway, New Jersey 08854, USA
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38
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Lee HM, Won KJ, Kim J, Park HJ, Kim HJ, Roh HY, Lee SH, Lee CK, Kim B. Endothelin-1 Induces Contraction via a Syk-Mediated p38 Mitogen-Activated Protein Kinase Pathway in Rat Aortic Smooth Muscle. J Pharmacol Sci 2007; 103:427-33. [PMID: 17409631 DOI: 10.1254/jphs.fp0070039] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
Although spleen tyrosine kinase (Syk) has crucial roles in various cells, its function on vascular smooth muscle contraction has not been determined. In the present study, we performed experiments to determine if Syk contributes to the endothelin-1 (ET-1)-mediated contraction in rat aortic smooth muscle. ET-1-induced contraction of aortic strips was inhibited by piceatannol, PD98059, and SB203580, inhibitors of Syk, extracellular signal-regulated kinase 1/2 (ERK1/2), and p38 mitogen-activated protein kinase (MAPK), respectively. Piceatannol also attenuated high K(+)-induced contraction. ET-1 dose-dependently enhanced the activity of Syk and this was inhibited by piceatannol in both rat aortic strip and rat aortic smooth muscle cells. The phosphorylation of p38 MAPK and heat shock protein 27 (HSP27), but not that of ERK1/2, in response to ET-1 was inhibited by both piceatannol and SB203580. These results suggest that Syk may play an important role in the regulation of aortic smooth muscle contraction induced by ET-1, which may be mediated by the p38 MAPK/HSP27 signaling pathway.
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MESH Headings
- Animals
- Anti-Inflammatory Agents, Non-Steroidal/pharmacology
- Aorta/cytology
- Aorta/drug effects
- Aorta/physiology
- Calcium-Calmodulin-Dependent Protein Kinases/antagonists & inhibitors
- Cells, Cultured
- Dose-Response Relationship, Drug
- Endothelin-1/pharmacology
- Enzyme Inhibitors/pharmacology
- Flavonoids/pharmacology
- Imidazoles/pharmacology
- Immunoblotting
- Immunoprecipitation
- In Vitro Techniques
- Intracellular Signaling Peptides and Proteins/antagonists & inhibitors
- Intracellular Signaling Peptides and Proteins/metabolism
- Male
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/physiology
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/metabolism
- Phosphorylation/drug effects
- Protein-Tyrosine Kinases/antagonists & inhibitors
- Protein-Tyrosine Kinases/metabolism
- Pyridines/pharmacology
- Rats
- Rats, Sprague-Dawley
- Stilbenes/pharmacology
- Syk Kinase
- Vasoconstriction/drug effects
- p38 Mitogen-Activated Protein Kinases/antagonists & inhibitors
- p38 Mitogen-Activated Protein Kinases/metabolism
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Affiliation(s)
- Hwan Myung Lee
- Department of Physiology, College of Medicine, Konkuk University, Danwol-dong, Chungju, Korea
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Gu Z, Kordowska J, Williams GL, Wang CLA, Hai CM. Erk1/2 MAPK and caldesmon differentially regulate podosome dynamics in A7r5 vascular smooth muscle cells. Exp Cell Res 2006; 313:849-66. [PMID: 17239373 PMCID: PMC2040298 DOI: 10.1016/j.yexcr.2006.12.005] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2006] [Revised: 12/05/2006] [Accepted: 12/06/2006] [Indexed: 01/27/2023]
Abstract
We tested the hypothesis that the MEK/Erk/caldesmon phosphorylation cascade regulates PKC-mediated podosome dynamics in A7r5 cells. We observed the phosphorylation of MEK, Erk and caldesmon, and their translocation to the podosomes upon phorbol dibutyrate (PDBu) stimulation, together with the nuclear translocation of phospho-MEK and phospho-Erk. After MEK inhibition by U0126, Erk translocated to the interconnected actin-rich columns but failed to translocate to the nucleus, suggesting that podosomes served as a site for Erk phosphorylation. The interconnected actin-rich columns in U0126-treated, PDBu-stimulated cells contained alpha-actinin, caldesmon, vinculin, and metalloproteinase-2. Caldesmon and vinculin became integrated with F-actin at the columns, in contrast to their typical location at the ring of podosomes. Live-imaging experiments suggested the growth of these columns from podosomes that were slow to disassemble. The observed modulation of podosome size and life time in A7r5 cells overexpressing wild-type and phosphorylation-deficient caldesmon-GFP mutants in comparison to untransfected cells suggests that caldesmon and caldesmon phosphorylation modulate podosome dynamics in A7r5 cells. These results suggest that Erk1/2 and caldesmon differentially modulate PKC-mediated formation and/or dynamics of podosomes in A7r5 vascular smooth muscle cells.
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Affiliation(s)
- Zhizhan Gu
- Department of Molecular Pharmacology, Physiology & Biotechnology, Brown University, Providence, RI 02912
| | | | - Geoffrey L. Williams
- Department of Molecular Biology, Cell Biology & Biochemistry, Brown University, Providence, RI 02912
| | | | - Chi-Ming Hai
- Department of Molecular Pharmacology, Physiology & Biotechnology, Brown University, Providence, RI 02912
- *Correspondence: Chi-Ming Hai, Ph.D., Department of Molecular Pharmacology, Physiology & Biotechnology, Box G-B3, Brown University, Providence, RI 02912, Tel. (401) 863-3288, Fax. (401) 863-1222, Email.
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Huang R, Cao GJ, Guo H, Kordowska J, Wang CLA. Direct interaction between caldesmon and cortactin. Arch Biochem Biophys 2006; 456:175-82. [PMID: 16962992 PMCID: PMC1847647 DOI: 10.1016/j.abb.2006.07.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2006] [Revised: 07/15/2006] [Accepted: 07/30/2006] [Indexed: 01/04/2023]
Abstract
Actin polymerization and depolymerization plays a central role in controlling a wide spectrum of cellular processes. There are many actin-binding proteins in eukaryotic cells. Their roles in the remodeling of the actin architecture and whether they work cooperatively await further study. Caldesmon (CaD) is an actin-binding protein present in nearly all mammalian cells. Cortactin is another actin-binding protein found mainly in the cell cortex. There have been no reports suggesting that CaD and cortactin interact with each other or work as partners. Here, we present evidence that CaD binds cortactin directly by overlay, pull-down assays, ELISA, and by column chromatography. The interaction involves the N-terminal region of cortactin and the C-terminal region of CaD, and appears to be enhanced by divalent metal ions. Cortactin competes with both full-length CaD and its C-terminal fragment for actin binding. Binding of cortactin partially alleviates the inhibitory effect of CaD on the actomyosin ATPase activity. Not only can binding be demonstrated in vitro, the two proteins also co-localize in activated cells at the cortex. Whether such interactions bear any functional significance awaits further investigation.
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Affiliation(s)
| | | | | | | | - C.-L. Albert Wang
- Corresponding author at 64 Grove St., Watertown, MA 02472, Tel: 617-658-7803, Fax: 617-972-1753, Email Address:
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Kordowska J, Huang R, Wang CLA. Phosphorylation of caldesmon during smooth muscle contraction and cell migration or proliferation. J Biomed Sci 2006; 13:159-72. [PMID: 16453176 DOI: 10.1007/s11373-005-9060-8] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
The actin-binding protein caldesmon (CaD) exists both in smooth muscle (the heavy isoform, h-CaD) and non-muscle cells (the light isoform, l-CaD). In smooth muscles h-CaD binds to myosin and actin simultaneously and modulates the actomyosin interaction. In non-muscle cells l-CaD binds to actin and stabilizes the actin stress fibers; it may also mediate the interaction between actin and non-muscle myosins. Both h- and l-CaD are phosphorylated in vivo upon stimulation. The major phosphorylation sites of h-CaD when activated by phorbol ester are the Erk-specific sites, modification of which is attenuated by the MEK inhibitor PD98059. The same sites in l-CaD are also phosphorylated when cells are stimulated to migrate, whereas in dividing cells l-CaD is phosphorylated more extensively, presumably by cdc2 kinase. Both Erk and cdc2 are members of the MAPK family. Thus it appears that CaD is a downstream effector of the Ras signaling pathways. Significantly, the phosphorylatable serine residues shared by both CaD isoforms are in the C-terminal region that also contains the actin-binding sites. Biochemical and structural studies indicated that phosphorylation of CaD at the Erk sites is accompanied by a conformational change that partially dissociates CaD from actin. Such a structural change in h-CaD exposes the myosin-binding sites on the actin surface and allows actomyosin interactions in smooth muscles. In the case of non-muscle cells, the change in l-CaD weakens the stability of the actin filament and facilitates its disassembly. Indeed, the level of l-CaD modification correlates very well in a reciprocal manner with the level of actin stress fibers. Since both cell migration and cell division require dynamic remodeling of actin cytoskeleton that leads to cell shape changes, phosphorylation of CaD may therefore serve as a plausible means to regulate these processes. Thus CaD not only links the smooth muscle contractility and non-muscle motility, but also provides a common mechanism for the regulation of cell migration and cell proliferation.
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Affiliation(s)
- Jolanta Kordowska
- Boston Biomedical Research Institute, 64 Grove Street, 02472, Watertown, MA, USA
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42
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Eves R, Webb BA, Zhou S, Mak AS. Caldesmon is an integral component of podosomes in smooth muscle cells. J Cell Sci 2006; 119:1691-702. [PMID: 16595550 DOI: 10.1242/jcs.02881] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Podosomes are highly dynamic actin-based structures commonly found in motile and invasive cells such as macrophages, osteoclasts and vascular smooth muscle cells. Here, we have investigated the role of caldesmon, an actin-binding protein, in the formation of podosomes in aortic smooth muscle A7r5 cells induced by the phorbol ester PDBu. We found that endogenous low molecular weight caldesmon (l-caldesmon), which was normally localised to actin-stress fibres and membrane ruffles, was recruited to the actin cores of PDBu-induced podosomes. Overexpression of l-caldesmon in A7r5 cells caused dissociation of actin-stress fibres and disruption of focal adhesion complexes, and significantly reduced the ability of PDBu to induce podosome formation. By contrast, siRNA interference of caldesmon expression enhanced PDBu-induced formation of podosomes. The N-terminal fragment of l-caldesmon, CaD40, which contains the myosin-binding site, did not label stress fibres and was not translocated to PDBu-induced podosomes. Cad39, the C-terminal fragment housing the binding sites for actin, tropomyosin and calmodulin, was localised to stress fibres and was translocated to podosomes induced by PDBu. The caldesmon mutant, CadCamAB, which does not interact with Ca2+/calmodulin, was not recruited to PDBu-induced podosomes. These results show that (1) l-caldesmon is an integral part of the actin-rich core of the podosome; (2) overexpression of l-caldesmon suppresses podosome formation, whereas siRNA knock-down of l-caldesmon facilitates its formation; and (3) the actin-binding and calmodulin-binding sites on l-caldesmon are essential for the translocation of l-caldesmon to the podosomes. In summary, this data suggests that caldesmon may play a role in the regulation of the dynamics of podosome assembly and that Ca2+/calmodulin may be part of a regulatory mechanism in podosome formation.
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Affiliation(s)
- Robert Eves
- Department of Biochemistry, and Protein Function Discovery Program, Queen's University, Kingston, ON K7L 3N6, Canada
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Hoffman LM, Jensen CC, Kloeker S, Wang CLA, Yoshigi M, Beckerle MC. Genetic ablation of zyxin causes Mena/VASP mislocalization, increased motility, and deficits in actin remodeling. ACTA ACUST UNITED AC 2006; 172:771-82. [PMID: 16505170 PMCID: PMC2063708 DOI: 10.1083/jcb.200512115] [Citation(s) in RCA: 127] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Focal adhesions are specialized regions of the cell surface where integrin receptors and associated proteins link the extracellular matrix to the actin cytoskeleton. To define the cellular role of the focal adhesion protein zyxin, we characterized the phenotype of fibroblasts in which the zyxin gene was deleted by homologous recombination. Zyxin-null fibroblasts display enhanced integrin-dependent adhesion and are more migratory than wild-type fibroblasts, displaying reduced dependence on extracellular matrix cues. We identified differences in the profiles of 75- and 80-kD tyrosine-phosphorylated proteins in the zyxin-null cells. Tandem array mass spectrometry identified both modified proteins as isoforms of the actomyosin regulator caldesmon, a protein known to influence contractility, stress fiber formation, and motility. Zyxin-null fibroblasts also show deficits in actin stress fiber remodeling and exhibit changes in the molecular composition of focal adhesions, most notably by severely reduced accumulation of Ena/VASP proteins. We postulate that zyxin cooperates with Ena/VASP proteins and caldesmon to influence integrin-dependent cell motility and actin stress fiber remodeling.
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Affiliation(s)
- Laura M Hoffman
- The Huntsman Cancer Institute and the Department of Biology,University of Utah, Salt Lake City, UT 84112, USA
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Seow CY. Myosin filament assembly in an ever-changing myofilament lattice of smooth muscle. Am J Physiol Cell Physiol 2006; 289:C1363-8. [PMID: 16275736 DOI: 10.1152/ajpcell.00329.2005] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A major development in smooth muscle research in recent years is the recognition that the myofilament lattice of the muscle is malleable. The malleability appears to stem from plastic rearrangement of contractile and cytoskeletal filaments in response to stress and strain exerted on the muscle cell, and it allows the muscle to adapt to a wide range of cell lengths and maintain optimal contractility. Although much is still poorly understood, we have begun to comprehend some of the basic mechanisms underlying the assembly and disassembly of contractile and cytoskeletal filaments in smooth muscle during the process of adaptation to large changes in cell geometry. One factor that likely facilitates the plastic length adaptation is the ability of myosin filaments to form and dissolve at the right place and the right time within the myofilament lattice. It is proposed herein that formation of myosin filaments in vivo is aided by the various filament-stabilizing proteins, such as caldesmon, and that the thick filament length is determined by the dimension of the actin filament lattice. It is still an open question as to how the dimension of the dynamic filament lattice is regulated. In light of the new perspective of malleable myofilament lattice in smooth muscle, the roles of many smooth muscle proteins could be assigned or reassigned in the context of plastic reorganization of the contractile apparatus and cytoskeleton.
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Affiliation(s)
- Chun Y Seow
- Department of Pathology and Laboratory Medicine, James Hogg iCAPTURE Centre, St. Paul's Hospital, Rm. 166, 1081 Burrard St., Vancouver, BC, Canada V6Z 1Y6.
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Huang R, Wang CLA. A caldesmon peptide activates smooth muscle via a mechanism similar to ERK-mediated phosphorylation. FEBS Lett 2005; 580:63-6. [PMID: 16343491 DOI: 10.1016/j.febslet.2005.11.047] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2005] [Revised: 11/16/2005] [Accepted: 11/18/2005] [Indexed: 10/25/2022]
Abstract
Caldesmon (CaD) is thought to regulate smooth muscle contraction, because it binds actin and inhibits actomyosin interactions. A synthetic actin-binding peptide (GS17C) corresponding to Gly666-Ser682 of chicken gizzard CaD has been shown to induce force development in permeabilized smooth muscle cells. The mechanism of GS17C's action remains unclear, although a structural effect was postulated. By photo-crosslinking and fluorescence quenching experiments with a gizzard CaD fragment (H32K; Met563-Pro771) and its mutants, we showed that GS17C indeed dissociated the C-terminal region of H32K from actin, in a manner similar to extracellular signal-regulated kinase-mediated phosphorylation, thereby reversing the CaD-imposed inhibition and enabling the actomyosin interaction.
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Affiliation(s)
- Renjian Huang
- Boston Biomedical Research Institute, Muscle and Motility Group, 64 Grove St., Watertown, MA 02472, USA
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46
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Abstract
Caldesmon is an actin-binding protein that is capable of stabilizing actin filaments against actin-severing proteins, inhibiting actomyosin ATPase activity, and inhibiting Arp2/3-mediated actin polymerization in vitro. Caldesmon is a substrate of cdc2 kinase and Erk1/2 MAPK, and phosphorylation by either of these kinases reverses the inhibitory effects of caldesmon. Cdc2-mediated caldesmon phosphorylation and the resulting dissociation of caldesmon from actin filaments are essential for M-phase progression during mitosis. Cells overexpressing the actin-binding carboxyterminal fragment of caldesmon fail to release the fragment completely from actin filaments during mitosis, resulting in a higher frequency of multinucleated cells. PKC-mediated MEK/Erk/caldesmon phosphorylation is an important signaling cascade in the regulation of smooth muscle contraction. Furthermore, PKC activation has been shown to remodel actin stress fibers into F-actin-enriched podosome columns in cultured vascular smooth muscle cells. Podosomes are cytoskeletal adhesion structures associated with the release of metalloproteases and degradation of extracellular matrix during cell invasion. Interestingly, caldesmon is one of the few actin-binding proteins that is associated with podosomes but excluded from focal adhesions. Caldesmon also inhibits the function of gelsolin and Arp2/3 complex that are essential for the formation of podosomes. Thus, caldesmon appears to be well positioned for playing a modulatory role in the formation of podosomes. Defining the roles of actin filament-stabilizing proteins such as caldesmon and tropomyosin in the formation of podosomes should provide a more complete understanding of molecular systems that regulate the remodeling of the actin cytoskeleton in cell transformation and invasion.
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Affiliation(s)
- Chi-Ming Hai
- Department of Molecular Pharmacology, Physiology & Biotechnology, Brown University, Box G-B3, Providence, RI 02912, USA.
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Terakawa M, Tomimori Y, Goto M, Hayashi Y, Oikawa S, Fukuda Y. Eosinophil migration induced by mast cell chymase is mediated by extracellular signal-regulated kinase pathway. Biochem Biophys Res Commun 2005; 332:969-75. [PMID: 15919053 DOI: 10.1016/j.bbrc.2005.04.172] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2005] [Accepted: 04/14/2005] [Indexed: 01/11/2023]
Abstract
Mast cell chymase is known to induce eosinophil migration in vivo and in vitro. In the present study, we investigated possible involvement of mitogen-activated protein (MAP) kinases; extracellular signal-regulated kinase (ERK), c-Jun amino-terminal kinase (JNK), and p38, in the chymase-induced eosinophil migration. Human chymase induced a rapid phosphorylation of ERK1/2 and p38 in human eosinophilic leukemia EoL-1 cells, while no phosphorylation was detected in JNK. The chymase-induced phosphorylation of ERK and p38 was inhibited by pertussis toxin. Similar results were obtained in the experiments using mouse chymase and eosinophils. U0126 (the inhibitor for MAP/ERK kinase) suppressed chymase-induced migration of EoL-1 cells and mouse eosinophils. However, SB203580 (p38 inhibitor) and SP600125 (JNK inhibitor) showed little effect on the migration. It is suggested therefore that chymase activates ERK and p38 probably through G-protein-coupled receptor, and that ERK but not p38 cascade may have a crucial role in chymase-induced migration of eosinophils.
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Affiliation(s)
- Maki Terakawa
- Daiichi Suntory Biomedical Research Limited, 1-1-1 Wakayamadai, Shimamoto-cho, Mishima-gun, Osaka 618-8513, Japan
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Guo H, Wang CLA. Specific disruption of smooth muscle caldesmon expression in mice. Biochem Biophys Res Commun 2005; 330:1132-7. [PMID: 15823561 DOI: 10.1016/j.bbrc.2005.03.089] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2005] [Indexed: 01/27/2023]
Abstract
Caldesmon (CaD) is an actin-binding protein that is capable of inhibiting the actomyosin ATPase activity in vitro. CaD has a single gene that is alternatively spliced to generate the smooth muscle-specific form, h-CaD, and a shorter isoform, l-CaD, that is present only in non-muscle cells. The difference between h- and l-CaD is a highly charged repeating sequence, corresponding to a 35 nm-long single helical region that separates the N-terminal domain from the C-terminal domain of h-CaD. To test whether such an elongated h-CaD is essential for smooth muscles to function properly, we have specifically abrogated its expression in the mouse by targeting h-CaD without affecting the expression of l-CaD. After genotyping, we have obtained homozygous knockout mice that indeed lack h-CaD, but nevertheless express varying amounts of l-CaD in a tissue-dependent fashion. The contractility of smooth muscles isolated from the knockout animals is currently under investigation.
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Affiliation(s)
- Hongqiu Guo
- Boston Biomedical Research Institute, 64 Grove Street, Watertown, MA 02472, USA
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Gangopadhyay SS, Takizawa N, Gallant C, Barber AL, Je HD, Smith TC, Luna EJ, Morgan KG. Smooth muscle archvillin: a novel regulator of signaling and contractility in vascular smooth muscle. J Cell Sci 2004; 117:5043-57. [PMID: 15383618 DOI: 10.1242/jcs.01378] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The mechanisms by which protein kinase C (PKC) and extracellular-signal-regulated kinases (ERK1/2) govern smooth-muscle contractility remain unclear. Calponin (CaP), an actin-binding protein and PKC substrate, mediates signaling through ERK1/2. We report here that CaP sequences containing the CaP homology (CH) domain bind to the C-terminal 251 amino acids of smooth-muscle archvillin (SmAV), a new splice variant of supervillin, which is a known actin- and myosin-II-binding protein. The CaP-SmAV interaction is demonstrated by reciprocal yeast two-hybrid and blot-overlay assays and by colocalization in COS-7 cells. In differentiated smooth muscle, endogenous SmAV and CaP co-fractionate and co-translocate to the cell cortex after stimulation by agonist. Antisense knockdown of SmAV in tissue inhibits both the activation of ERK1/2 and contractions stimulated by either agonist or PKC activation. This ERK1/2 signaling and contractile defect is similar to that observed in CaP knockdown experiments. In A7r5 smooth-muscle cells, PKC activation by phorbol esters induces the reorganization of endogenous, membrane-localized SmAV and microfilament-associated CaP into podosome-like structures that also contain F-actin, nonmuscle myosin IIB and ERK1/2. These results indicate that SmAV contributes to the regulation of contractility through a CaP-mediated signaling pathway, involving PKC activation and phosphorylation of ERK1/2.
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Ono K, Ono S. Tropomyosin and troponin are required for ovarian contraction in the Caenorhabditis elegans reproductive system. Mol Biol Cell 2004; 15:2782-93. [PMID: 15064356 PMCID: PMC420102 DOI: 10.1091/mbc.e04-03-0179] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Ovulation in the nematode Caenorhabditis elegans is coordinated by interactions between the somatic gonad and germ cells. Myoepithelial sheath cells of the proximal ovary are smooth muscle-like cells, but the regulatory mechanism of their contraction is unknown. We show that contraction of the ovarian muscle requires tropomyosin and troponin, which are generally major actin-linked regulators of contraction of striated muscle. RNA interference of tropomyosin or troponin C caused sterility by inhibiting ovarian contraction that is required for expelling mature oocytes into the spermatheca where fertilization takes place, thus causing accumulation of endomitotic oocytes in the ovary. Tropomyosin and troponin C were associated with actin filaments in the myoepithelial sheath, and the association of troponin C with actin was dependent on tropomyosin. A mutation in the actin depolymerizing factor/cofilin gene suppressed the ovulation defects by RNA interference of tropomyosin or troponin C. These results strongly suggest that tropomyosin and troponin are the actin-linked regulators for contraction of ovarian muscle in the C. elegans reproductive system.
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Affiliation(s)
- Kanako Ono
- Department of Pathology, Emory University, Atlanta, Georgia 30322, USA
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