title: Development and metamorphosis of the larvae of Ascidia malaca in different experimental conditions.
abstract: In larvae of Ascidia malaca that have developed in sea-water without sulphate ions, the cells of the caphalo-ventral region are devoid of sulphated mucopolysaccharides, and the chordal and muscular cells of the tail turn out to be altered; after metamorphosis no adhesive ampullae appear. The addition of cysteine to water lacking sulphate ions leads to a normal synthesis of sulphated mucopolysaccharides in the cells of the cephalo-ventral region, and to a normal secretion of matrix by the chordal cells; but the larvae do not regain the ability to swim. The addition of N-dichloroacetyl-DL-phenylalanine to sea-water does not alter the synthesis of sulphated mucopolysaccharides in the cells of the cephalo-ventral region, but, probably by acting as a competitive inhibitor of phenylalanine, it causes alterations in the muscular cells of the tail.
mesh_terms: D003545:Cysteine / Q000494:pharmacology; D006025:Glycosaminoglycans / Q000378:metabolism; D007814:Larva / Q000254:growth & development / Q000378:metabolism; D008278:Magnesium Sulfate / Q000494:pharmacology; D008675:Metamorphosis, Biological; D010649:Phenylalanine / Q000031:analogs & derivatives / Q000494:pharmacology; D011506:Proteins / Q000378:metabolism; D014561:Urochordata / Q000196:embryology*
chemical_list: D006025:Glycosaminoglycans; D011506:Proteins; C014465:N-dichloroacetyl-DL-phenylalanine; D010649:Phenylalanine; D008278:Magnesium Sulfate; D003545:Cysteine