ROLE OF PROTEOGLYCAN IN THE DEVELOPMENT OF SEA-URCHINS .1. ABNORMAL-DEVELOPMENT OF SEA-URCHIN EMBRYOS CAUSED BY THE DISTURBANCE OF PROTEOGLYCAN SYNTHESIS

The development of the sea urchins, Hemicentrotus pulcherrimus and Clypeaster japonicus, was examined under conditions which inhibit the synthesis of proteoglycan in various ways. The changes in the developmental fate were compared with the degree of inhibition of proteoglycan synthesis as measured by incorporation of labeled precursors. The inhibition of proteoglycan synthesis was achieved by treating the embryos with (1) aryl-β-d-xyloside (inhibition of coupling between protein and polysaccharide moieties); (2) sodium selenate (inhibition of sulfation of polysaccharide); and (3) 2-deoxy-d-glucose (inhibition of polysaccharide chain elongation). It was found that the development of embryos ceased at the blastula stage in all cases tested, irrespective of the step of the inhibition. The cessation of development became apparent when the incorporation of the labeled precursors was decreased to a level below 50% compared with the normal level. From these facts, it appears that the synthesis of proteoglycan is necessary for the realization of post-gastrular development. © 1979.