Stabilization and swelling of hagfish slime mucin vesicles
Open Access
- 1 April 2010
- journal article
- Published by The Company of Biologists in Journal of Experimental Biology
- Vol. 213 (7), 1092-1099
- https://doi.org/10.1242/jeb.038992
Abstract
SUMMARY When agitated, Atlantic hagfish (Myxine glutinosa) produce large quantities of slime that consists of hydrated bundles of protein filaments and membrane-bound mucin vesicles from numerous slime glands. When the slime exudate contacts seawater, the thread bundles unravel and the mucin vesicles swell and rupture. Little is known about the mechanisms of vesicle rupture in seawater and stabilization within the gland, although it is believed that the vesicle membrane is permeable to most ions except polyvalent anions. We hypothesized that the most abundant compounds within the slime gland exudate have a stabilizing effect on the mucin vesicles. To test this hypothesis, we measured the chemical composition of the fluid component of hagfish slime exudate and conducted functional assays with these solutes to test their ability to keep the vesicles in a condensed state. We found K+ concentrations that were elevated relative to plasma, and Na+, Cl− and Ca2+ concentrations that were considerably lower. Our analysis also revealed high levels of methylamines such as trimethylamine oxide (TMAO), betaine and dimethylglycine, which had a combined concentration of 388 mmol l−1 in the glandular fluid. In vitro rupture assays demonstrated that both TMAO and betaine had a significant effect on rupture, but neither was capable of completely abolishing mucin swelling and rupture, even at high concentrations. This suggests that some other mechanism such as the chemical microenvironment within gland mucous cells, or hydrostatic pressure is responsible for stabilization of the vesicles within the gland.This publication has 24 references indexed in Scilit:
- Composition, morphology and mechanics of hagfish slimeJournal of Experimental Biology, 2005
- Inhibitory Mechanism of Store-operated Ca2+ Channels by ZincJournal of Biological Chemistry, 2004
- High Contents of Trimethylamine Oxide Correlating With Depth in Deep-Sea Teleost Fishes, Skates, and Decapod CrustaceansThe Biological Bulletin, 1999
- Betaine is the principal counteracting osmolyte in tissues of the elephant fish, Callorhincus millii (Elasmobranchii, Holocephali)Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology, 1998
- Lead and zinc block a voltage-activated calcium channel of Aplysia neuronsJournal of Neurophysiology, 1991
- The stabilization of proteins by osmolytesBiophysical Journal, 1985
- The Hagfish Slime Gland: A Model System for Studying the Biology of MucusScience, 1981
- Thread Cells from the Slime Glands of Hagfish (Myxinidae)Acta Zoologica, 1981
- Studies on Myxine glutinosa—I. The chemical composition of the tissuesComparative Biochemistry and Physiology, 1961
- A FIBROUS PROTEIN FROM THE SLIME OF THE HAGFISHPublished by Elsevier ,1941