Lectin histochemistry of the hyaline layer around the larvae of Patiriella species (Asteroidea) with different developmental modes.
Larvae of sea stars are surrounded by an extracellular matrix called the hyaline layer. The lectin-binding properties of this matrix were investigated in an ultrastructural study of Patiriella species having different modes of development. The planktonic bipinnaria and brachiolaria of P. regularis and the planktonic brachiolaria of P. calcar demonstrated the same labeling of the hyaline layer for three lectins: Con A, SBA, and WGA. In both species the outer coarse meshwork stained for all three lectins, whereas the intervillous layer displayed patchy labeling. In the benthic brachiolaria of P. exigua, the outer coarse meshwork displayed heavy labeling for all three lectins. The heavy labeling of the outer coarse meshwork of P. exigua compared with that of the other species suggests an increased number of lectin binding sites in the hyaline layer of this species. The similar ultrastructure and histochemistry of the hyaline layer of P. regularis and P. calcar may reflect similar requirements of their extracellular cover in their planktonic environment. Lectin labeling shows that hypertrophy of the hyaline layer of P. exigua, in particular the outer coarse meshwork, involves elaboration of the carbohydrate composition of the matrix. Modifications seen in the ultrastructure and histochemistry of the hyaline layer of P. exigua appear to be associated with the evolution of benthic development.
Cerra
A
A
Department of Anatomy, University of Sydney, NSW, Australia. anna@anatomy.usyd.edu.au
D000818:Animals; D050260:Carbohydrate Metabolism; D004447:Echinodermata / Q000254:growth & development / Q000378:metabolism*; D006651:Histocytochemistry; D006818:Hyalin / Q000378:metabolism*; D007814:Larva; D037102:Lectins / Q000378:metabolism*; D013045:Species Specificity
D037102:Lectins