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

First published online October 7, 2005
Journal of Experimental Biology 208, 3819-3834 (2005)
Published by The Company of Biologists 2005
doi: 10.1242/jeb.01765

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 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 Megill, W. M. Articles by Blake, R. W. Search for Related Content PubMed PubMed Citation Articles by Megill, W. M. Articles by Blake, R. W. Social Bookmarking                         What's this?

The modulus of elasticity of fibrillin-containing elastic fibres in the mesoglea of the hydromedusa Polyorchis penicillatus

William M. Megill^1,2,3,*, John M. Gosline^1,2 and Robert W. Blake^1,2

¹ Department of Zoology, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
² Bamfield Marine Sciences Centre, Bamfield, BC, V0R 1B0, Canada
³ Centre for Biomimetic and Natural Technologies, Mechanical Engineering Department, University of Bath, Bath, BA2 7AY, UK

^* Author for correspondence (e-mail: megillw{at}cerf.bc.ca)

Accepted 23 June 2005

Hydromedusan jellyfish swim by rhythmic pulsation of their mesogleal bells. A single swimming muscle contracts to create thrust by ejecting water from the subumbrellar cavity. At the end of the contraction, energy stored in the deformation of the mesogleal bell powers the refilling stage, during which water is sucked back into the subumbrellar cavity. The mesoglea is a mucopolysaccharide gel reinforced with radially oriented fibres made primarily of a protein homologous to mammalian fibrillin. Most of the energy required to power the refill stroke is thought to be stored by stretching these fibres. The elastic modulus of similar fibrillin-rich fibres has been measured in other systems and found to be in the range of 0.2 to 1.1 MPa. In this paper, we measured the diameters of the fibres, their density throughout the bell, and the mechanical behaviour of the mesoglea, both in isolated samples and in an intact bell preparation. Using this information, we calculated the stiffness of the fibres of the hydromedusa Polyorchis penicillatus, which we found to be approximately 0.9 MPa, similar in magnitude to other species. This value is two orders of magnitude more compliant than the stiffness of the component fibrillin microfibrils previously reported. We show that the structure of the radial fibres can be modelled as a parallel fibre-reinforced composite and reconcile the stiffness difference by reinterpreting the previously reported data. We separate the contributions to the bell elasticity of the fibres and mesogleal matrix and calculate the energy storage capacity of the fibres using the calculated value of their stiffness and measured densities and diameters. We conclude that there is enough energy potential in the fibres alone to account for the energy required to refill the subumbrellar cavity.

Key words: microfibril, modulus of elasticity, mechanical property, mesoglea, jellyfish, extracellular matrix, fibrillin, elastic fibre, Polyorchis penicillatus

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?

This article has been cited by other articles:

				J. E. Wagenseil and R. P. Mecham Vascular Extracellular Matrix and Arterial Mechanics Physiol Rev, July 1, 2009; 89(3): 957 - 989. [Abstract] [Full Text] [PDF]

				M. J. McHenry and S. M. van Netten The flexural stiffness of superficial neuromasts in the zebrafish (Danio rerio) lateral line J. Exp. Biol., December 1, 2007; 210(23): 4244 - 4253. [Abstract] [Full Text] [PDF]

				C. M Kielty, S. Stephan, M. J Sherratt, M. Williamson, and C. A. Shuttleworth Applying elastic fibre biology in vascular tissue engineering Phil Trans R Soc B, August 29, 2007; 362(1484): 1293 - 1312. [Abstract] [Full Text] [PDF]