The project aims to study the transcriptomes of immune-related tissues from strongylocentrotus intermedius, native to north Hokkaido of Japan and Sakhalin Island of Russian in Far East. The coelomocytes in coelomic fluid of adult sea urchin had been considered as the main mediator of immune response. The immune response could be activated in peristomial membrane and intestine because they were exposed to the pathogens from the environments. The immune-related genes of sea urchin will be explored by transcriptome analysis. The molecular mechanism of immune response will be studied furtherly.