QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

First published online May 28, 2005
doi: 10.1242/10.1242/jcs.02368

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Related articles in JCS Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Herrera, A. M. Articles by Seow, C. Y. Search for Related Content PubMed PubMed Citation Articles by Herrera, A. M. Articles by Seow, C. Y.

`Sarcomeres' of smooth muscle: functional characteristics and ultrastructural evidence

¹ Department of Pathology and Laboratory Medicine, St Paul's Hospital/Providence Health Care, University of British Columbia, 1081 Burrard Street, Vancouver, BC V6Z 1Y6, Canada
² Department of Medicine, St Paul's Hospital/Providence Health Care, University of British Columbia, 1081 Burrard Street, Vancouver, BC V6Z 1Y6, Canada
³ James Hogg iCAPTURE Centre for Cardiovascular and Pulmonary Research, St Paul's Hospital/Providence Health Care, University of British Columbia, 1081 Burrard Street, Vancouver, BC V6Z 1Y6, Canada

^* Author for correspondence (e-mail: cseow{at}mrl.ubc.ca)

Accepted 9 March 2005

Smooth muscle cells line the walls of hollow organs and control the organ dimension and mechanical function by generating force and changing length. Although significant progress has been made in our understanding of the molecular mechanism of actomyosin interaction that produces sliding of actin (thin) and myosin (thick) filaments in smooth muscle, the sarcomeric structure akin to that in striated muscle, which allows the sliding of contractile filaments to be translated into cell shortening has yet to be elucidated. Here we show evidence from porcine airway smooth muscle that supports a model of malleable sarcomeric structure composed of contractile units assembled in series and in parallel. The geometric organization of the basic building blocks (contractile units) within the assembly and the dimension of individual contractile units can be altered when the muscle cells adapt to different lengths. These structural alterations can account for the different length-force relationships of the muscle obtained at different adapted cell lengths. The structural malleability necessary for length adaptation precludes formation of a permanent filament lattice and explains the lack of aligned filament arrays in registers, which also explains why smooth muscle is `smooth'.

Key words: Isotonic shortening, Plasticity, Contraction mechanism, Length adaptation, Ultrastructure

Related articles in JCS:

Smoothing out muscle

JCS 2005 118: 1104. [Full Text]  

This article has been cited by other articles:

				Y. Bosse, L. Y. M. Chin, P. D. Pare, and C. Y. Seow Adaptation of Airway Smooth Muscle to Basal Tone: Relevance to Airway Hyperresponsiveness Am. J. Respir. Cell Mol. Biol., January 1, 2009; 40(1): 13 - 18. [Abstract] [Full Text] [PDF]

				R. J. Chi, A. R. Simon, E. A. Bienkiewicz, A. Felix, and T. C. S. Keller III Smooth Muscle Titin Zq Domain Interaction with the Smooth Muscle {alpha}-Actinin Central Rod J. Biol. Chem., July 25, 2008; 283(30): 20959 - 20967. [Abstract] [Full Text] [PDF]

				D. D. Tang and Y. Anfinogenova Physiologic Properties and Regulation of the Actin Cytoskeleton in Vascular Smooth Muscle Journal of Cardiovascular Pharmacology and Therapeutics, June 1, 2008; 13(2): 130 - 140. [Abstract] [PDF]

				I. Wang, A. Z. Politi, N. Tania, Y. Bai, M. J. Sanderson, and J. Sneyd A Mathematical Model of Airway and Pulmonary Arteriole Smooth Muscle Biophys. J., March 15, 2008; 94(6): 2053 - 2064. [Abstract] [Full Text] [PDF]

				Y. Bosse, A. Sobieszek, P. D. Pare, and C. Y. Seow Length Adaptation of Airway Smooth Muscle Proceedings of the ATS, January 1, 2008; 5(1): 62 - 67. [Abstract] [Full Text] [PDF]

				F. Ali, L. Chin, P. D. Pare, and C. Y. Seow Mechanism of partial adaptation in airway smooth muscle after a step change in length J Appl Physiol, August 1, 2007; 103(2): 569 - 577. [Abstract] [Full Text] [PDF]

				S. S. An, T. R. Bai, J. H. T. Bates, J. L. Black, R. H. Brown, V. Brusasco, P. Chitano, L. Deng, M. Dowell, D. H. Eidelman, et al. Airway smooth muscle dynamics: a common pathway of airway obstruction in asthma Eur. Respir. J., May 1, 2007; 29(5): 834 - 860. [Abstract] [Full Text] [PDF]

				J. E. Speich, C. Dosier, L. Borgsmiller, K. Quintero, H. P. Koo, and P. H. Ratz Adjustable passive length-tension curve in rabbit detrusor smooth muscle J Appl Physiol, May 1, 2007; 102(5): 1746 - 1755. [Abstract] [Full Text] [PDF]

				A. V. Smolensky and L. E. Ford The extensive length-force relationship of porcine airway smooth muscle J Appl Physiol, May 1, 2007; 102(5): 1906 - 1911. [Abstract] [Full Text] [PDF]

				P. S. P. Silveira, J. P. Butler, and J. J. Fredberg Length adaptation of airway smooth muscle: a stochastic model of cytoskeletal dynamics J Appl Physiol, December 1, 2005; 99(6): 2087 - 2098. [Abstract] [Full Text] [PDF]

				C. Y. Seow Myosin filament assembly in an ever-changing myofilament lattice of smooth muscle Am J Physiol Cell Physiol, December 1, 2005; 289(6): C1363 - C1368. [Abstract] [Full Text] [PDF]

				B. E. McParland, R. R. Tait, P. D. Pare, and C. Y. Seow The Role of Airway Smooth Muscle during an Attack of Asthma Simulated In Vitro Am. J. Respir. Cell Mol. Biol., November 1, 2005; 33(5): 500 - 504. [Abstract] [Full Text] [PDF]