Clypeaster japonicus

The development of embryos of the sea urchins, Hemicentrotus pulcherrimus and Clypeaster japonicus, is arrested at the blastula stage by treating them with reagents to inhibit proteoglycan synthesis. The formation of completely assembled proteoglycan in sufficient amounts is a prerequisite for the events occurring at the end of the blastula stage. 

Yoshino, K.-L, Takao, T, Yamaguchi, M., Shimonishi, Y, and Suzuki, N. (1990b) Derivatives of sperm-activating peptide 111 (Sap-111) associated with eggs of sand dollar, Clypeaster japonicus and Astriclypeus mannl Comp. Biochem. Physiol, 97B, 679-685. 

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