Environmental Biology of Fishes

, Volume 38, Issue 1–3, pp 151–157 | Cite as

Stabilization and sclerotization ofRaja erinacea egg capsule proteins

  • Thomas J. Koob
  • David L. Cox


Sclerotization of skate egg capsule occurs after secretion of capsule precursors from the shell gland and involves a form of quinone tanning in which catechols are introduced in utero and subsequently oxidized to quinones by catechol oxidase. A latent form of enzyme is incorporated in the capsular matrix during secretion. Oxidase activity increases concomitantly with increasing catechol and quinone contents. Six major proteins ranging in size from 95kDa to 20kDa comprise the skate egg capsule, all of which contain elevated levels of glycine, serine, proline and tyrosine. Hydroxyproline occurs in all but one protein, however, none has an amino acid composition typical of collagen. Solubilization of two proteins from pre-tanned capsule requires reducing agents indicating that an early event leading to matrix stabilization is mediated by disulfide bonds. Stabilization of the other proteins along with the disulfide bonded proteins directly correlates with increasing catechol content, catechol oxidase activity and quinone formation.

Key words

Egg encapsulation Quinone tanning Skate Elasmobranch 


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References cited

  1. Arnow, L.E. 1937. Colorimetric determination of the components of 3,4-dihydroxyphenylalanine-tyrosine mixtures. J. Biol. Chem. 118: 531–537.Google Scholar
  2. Bear, R.S. 1952. The structure of collagen fibrils. Adv. Prot. Chem. 7: 69–160.Google Scholar
  3. Bidlingmeyer, B.A., S.A. Cohen & T.L. Tarvin. 1984. Rapid analysis of amino acids using precolumn derivatization. J. Chromatog. 336: 93–104.Google Scholar
  4. Bobek, L., D.M. Rekosh, H. van Keulen & P.T. Lo Verde. 1986. Characterization of a female-specific cDNA derived from a developmentally regulated mRNA in the humen blood fluke Schistosoma mansoni. Proc. Nat. Acad. Sci. USA 83: 5544–5548.Google Scholar
  5. Brown, C.H. 1955. Egg capsule proteins of selachians and trout. Quart. J. Microscop. Sci. 96: 483–488.Google Scholar
  6. Cox, D.L., R.P. Mecham & T.J. Koob. 1987. Site-specific variation in amino acid composition of skate egg capsule (Raja erinacea Mitchell 1825). J. Exp. Mar. Biol. Ecol. 107: 71–74.Google Scholar
  7. Gross, J., B. Dumsha & N. Glazer. 1958. Comparative biochemistry of collagen. Some amino acids and carbohydrates. Biochim. Biophys. Acta 30: 293–297.Google Scholar
  8. Hussakof, L. & W.H. Welker. 1911. Chemical notes on the egg capsules of two species of sharks. Biochem. Bull. 1: 216–221.Google Scholar
  9. Jones, C.W., N. Rosenthal, G.C. Rodakis & F.C. Kafatos. 1979. Evolution of two major chorion multigene families as inferred from cloned cDNA and protein sequences. Cell 18: 1317–1332.Google Scholar
  10. Knight, D.P. & S. Hunt. 1974. Fibril structure of collagen in egg capsule of dogfish. Nature 249: 379–380.Google Scholar
  11. Knight, D.P. & S. Hunt. 1976. Fine structure of the dogfish egg case: a unique collagenous material. Tiss. Cell 8: 183–193.Google Scholar
  12. Koob, T.J. & D.L. Cox. 1990. Introduction and oxidation of catechols during the formation of the skate (Raja erinacea) egg capsule. J. Mar. Biol. Ass., U.K. 70: 395–411.Google Scholar
  13. Krishnan, G. 1959. Histochemical studies on the nature and formation of egg capsules of the shark Chiloscyllium griseum. Biol. Bull. (Woods Hole) 117: 298–307.Google Scholar
  14. Martinez-Cruzado, J.C., C. Swimmer, M.G. Fenerjian & F.C. Kafatos. 1988. Evolution of the autosomal chorion locus in Drosophila. I. General organization of the locus and sequence comparisons of geness15 ands19 in evolutionary distant species. Genetics 119: 663–677.Google Scholar
  15. Pau, R.N. 1987. Characterization of juvenile hormone-regulated cockroach oothecin genes. Insect Biochem. 17: 1075–1078.Google Scholar
  16. Rusaouen, M. 1976. The dogfish shell gland, a histochemical study. J. Exp. Mar. Biol. Ecol. 23: 267–283.Google Scholar
  17. Rusaouen, M. 1978. Étude ultrastructurale des zones à secrétions protéiques et glycoprotéiques de la gland nidamentaire de la rousette à maturité. Arch. d"Anat. Microscop. 67: 107–119.Google Scholar
  18. Rusaouen-Innocent, M. 1991. Tannage quinonique de la capsule ovigere de la Roussette Scyliorhinus canicula (Linné). Can. J. Zool. 68: 2553–2563.Google Scholar
  19. Rusaouen, M., J.-P. Pujol, J. Bocquet, A. Veillard & J.-P. Borel. 1978. Evidence of collagen in the egg capsule of the dogfish, Scyliorhinus canicula. Comp. Biochem. Physiol. 53B: 539–543.Google Scholar
  20. Spoerel, N., H.T. Nguyen & F.C. Kafatos. 1986. Gene regulation and evolution in the chorion locus of Bombyx mori. Structural and developmental characterization of four eggshell genes and their flanking DNA regions. J. Mol. Biol. 190: 23–35.Google Scholar
  21. Threadgold, L.T. 1957. A histochemical study of the shell gland of Scyliorhinus caniculus. J. Histochem. Cytochem. 5: 159–166.Google Scholar
  22. Vovelle, J. 1967. Sur la présence des groupes SH et SS dans la sécrétion de la glande nidamentaire chez Scyliorhinus canicula L. C.R. Acad. Sci., Paris 260: 5945–5947.Google Scholar
  23. Waite, J.H. & A. Rice-Ficht. 1989. A histidine-rich protein from the vitellaria of the liver fluke Fasciola hepatica. Biochem. 28: 6104–6110.Google Scholar
  24. Waite, J.H. & M.L. Tanzer. 1981. Specific colorimetric detection of o-diphenols and 3,4-dihydroxyphenylalanine-containing peptides. Analyt. Biochem. 3: 131–136.Google Scholar

Copyright information

© Kluwer Academic Publishers 1993

Authors and Affiliations

  • Thomas J. Koob
    • 1
  • David L. Cox
    • 1
    • 2
  1. 1.Mount Desert Island Biological LaboratorySalsbury CoveU.S.A.
  2. 2.Department of BiologyUniversity of OregonEugeneU.S.A.

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