[ report an error in this record ]basket (0): add | show Print this page

Initial stages of tunic morphogenesis in the ascidian Halocynthia: a fine structural study
Lübbering, B.; Nishikata, T.; Goffinet, G. (1992). Initial stages of tunic morphogenesis in the ascidian Halocynthia: a fine structural study. Tissue Cell 24(1): 121-130. https://dx.doi.org/10.1016/0040-8166(92)90086-M
In: Tissue and cell. Oliver and Boyd: Edinburgh. ISSN 0040-8166; e-ISSN 1532-3072, more
Peer reviewed article  

Available in  Authors 

    Ascidiacea [WoRMS]; Halocynthia Verrill, 1879 [WoRMS]
Author keywords

Authors  Top 
  • Lübbering, B.
  • Nishikata, T.
  • Goffinet, G., more

    Tunic morphogenesis in embryos of the ascidian Halocynthia roretzi was examined by scanning and transmission electron microscopy. For this purpose it was necessary to modify the classical embedding procedure. Soon after reaching the initial tail-bud stage, tunic deposition is initiated on the dorsal side of the embryo. As soon as the embryo is completely covered by the tunic, larval fins are formed. The test cells settle onto the embryo. At this stage only the outer cuticle and the outer tunic compartment have appeared. Tunic morphogenesis is accompanied by ultrastructural modifications of the epidermis characteristic of secreting cells. Cytochemical investigations reveal polysaccharide glycogen-like material in the lumen of epidermal lacunae and in the outer compartment of the tunic. Our observations strongly suggest that this material is stored in the lacunae and discharged into the outer compartment. The significance of fluffy osmiophilic material that appears at the early tail-bud stage and enlaces the whole embryo is discussed.

All data in the Integrated Marine Information System (IMIS) is subject to the VLIZ privacy policy Top | Authors