Summary
Transmission electron microscopy shows the gastric epithelium of Styela clava to comprise at least three distinct cell types. Ciliated mucous cells which form the crest of each stomach ridge produce mucus by an unexpected route. Vacuolated cells lining the ridge sides appear to be absorptive in function. Gastric enzymes are produced by typical protein secreting cells scattered amongst the vacuolated cells. Undifferentiated cells are found in the crypts between ridges. The structure and function of the gastric epithelium in Styela is discussed with special reference to the wider concepts of ascidian gut organization.
Similar content being viewed by others
References
Barrington, E.J.W.: Structure and function of the digestive system in Amphioxus. Phil. Trans B 228, 269–312 (1937)
Berrill, N.J.: Digestion in ascidians and the influence of temperature. J. exp. Biol. 6, 275–291 (1929)
Burighel, P.: Osservazioni morfologiche ed istochimiche sull'apparato digerente dell'ascidia coloniale Botrylloides leachii (Savigny). Acc. Pat. SC.LL.AA. 85, 117–132 (1973)
Burighel, P., Milanesi, C.: Fine structure of the gastric epithelium of the ascidian Botryllus schlosseri. Vacuolated and zymogenic cells. Z. Zellforsch 145, 541–555 (1973)
Burighel, P., Milanesi, C.: Fine structure of the gastric epithelium of the ascidian Botryllus schlosseri. Mucous, endocrine and plicated cells. Cell Tiss. Res. 158, 481–496 (1975)
Cheng, H.: Origin, differentiation and renewal of the 4 main epithelial cell types in the mouse small intestine, part 2, Mucous cells. Amer. J. Anat. 141, 481–501 (1974)
Degail, L., Levi, C.: Étude au microscope électronique de la glande digestive des Pyvridae (Ascidies). Cah. Biol. Mar. 5, 411–422 (1964)
Ermak, T.H.: Cell proliferation in the digestive tract of Styela clava (Urochordata: Ascidiacea) as revealed by a Autoradiography with tritiated thymidine. J. exp. Zool. 194, 449–466 (1975)
Fouque, G.: Contribution à l'étude de la glande pylorique des Ascidiacés. Ann. Inst. Ocean 28, 189–317 (1853)
Fouque, G.: Observations sur le “foie” de quelques Ascidies Stolidobranches. Rec. Trav. Stat. Mar. Endoume 29, 181–191 (1959)
Jamieson, J.D., Palade, G.E.: Role of the Golgi complex in the intracellular transport of secretory proteins. Proc. nat. Acad. Sci. (Wash.) 55, 424 (1966)
Koch, G.L.E., Marsh, C.: Glucosidase activities of the hepatopancreas of the ascidian Pyura stolonifera. Comp. Biochem. Physiol. 42, 577–590 (1972)
Millar, R.H.: Ciona, L.M.B.C. Memoirs, Liverpool: Coleman 1953
Morton, J.E.: The functions of the gut in ciliary feeders. Biol. Rev. 35, 92–140 (1960)
Neutra, M., Leblond, C.P.: Synthesis of the carbohydrate of mucus in the Golgi complex as shown by electron microscope radio-autography of goblet cells from rats injected with glucose H3. J. Cell Biol. 30, 119–136 (1966)
Orton, J.H.: The ciliary mechanisms of the gill and mode of feeding in Amphioxus, ascidians and Solenomya togata. J. mar. biol. Ass. U.K. 10, 19–49 (1913)
Palade, G.E.: Structure and function at the cellular level. J. Amer. med. Ass. 198, 815–825 (1966)
Parson, D.S., Boyd, C.A.R.: Transport across the intestinal mucosal cell: hierarchies of function. Int. Rev. Cytol. 32, 209–253 (1972)
Pérès, J.M.: Recherches sur le sang et les organes neuraux des Tuniciers. Ann. inst. oceanog. 21, 229–359 (1943)
Relini-Orsi, L.: Prime osservazioni morfologiche ed istochimiche sull'apparato digerente di Styela plicata, Les. Boll. Musei Ist. Biol. Univ. Genova 36, 157–184 (1968)
Relini-Orsi, L.: L'apparato digerente nei Tunicati: Aspetti istochimici e funzionali in Ciona intestinalis L. Boll. Musei Ist. Biol. Univ. Genova 37, 103–116 (1969)
Roule, M.L.: Recherches sur les Ascidies simples des Cotes de Provence. Phallusiadées. Monographic de la Ciona intestinalis. Ann. Mus. Hist. Nat. Marseilles 2, 1–270 (1884)
Stephens, R.J., Bils, R.F.: The ultrastructural changes in the developing chick liver. I. General cytology. J. Ultrastruct. Res. 18, 456–474 (1967)
Thomas, N.W.: Mucus secreting cells from the alimentary canal of Ciona intestinalis L. J. mar. biol. Ass. U.K. 50, 429–438 (1970a)
Thomas, N.W.: Morphology of cell types from the gastric epithelium of Ciona intestinalis L. J. mar. biol. Ass. U.K. 50, 757–746 (1970b)
Thorndyke, M.C., Bevis, P.J.R.: In preparation (1977)
Thorpe, A., Thorndyke, M.C., Barrington, E.J.W. Ultrastructural and histochemical features of the endostyle of the ascidian Ciona intestinalis with special reference to the distribution of bound iodine. Gen. comp. Endocr. 19, 559–571 (1972)
Toner, T.G.: Cytology of intestinal epithelial cells. Int. Rev. Cytol. 24, 233–324 (1968)
Weel, P.B. van: Beiträge zur Ernährungsbiologie der Ascidien. Pubbl. St. Zool. Napoli 18, 50–79 (1940)
Author information
Authors and Affiliations
Additional information
The author is grateful to Mrs. L. Rolph for technical help with scanning electron microscopy and Mr. J. Calvert and Mr. R. Jones for assistance with the transmission electron microscopy. Animals were collected through the kind offices of Mr. J. Sturges and other staff of the Admiralty Marine Trials Station, Portsmouth. This research was carried out during the tenure of SRC grant No. B/RG 82919 -The localization of polypeptide hormones in the pharynx and gut of Protochordates
Rights and permissions
About this article
Cite this article
Thorndyke, M.C. Observations on the gastric epithelium of ascidians with special reference to Styela clava . Cell Tissue Res. 184, 539–550 (1977). https://doi.org/10.1007/BF00220977
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00220977