Gene Expression Profiles of , and in Swimming Larva of Sea Cucumber .

The sea cucumber, , is one of the most valuable aquatic species. The color of body wall and appearance are important for the value of sea cucumbers. To examine expression pattern of (), (), and (), previously reported as differently expressed genes during the pigmentation of sea cucumber, we analyzed the temporal profiles of , , and mRNAs in LED-exposed and light-shielded . Real-time quantitative PCR revealed that the , , and mRNAs from the juveniles at 40-60 days post-fertilization (dpf) exhibited increasing patterns as compared to those of an early developmental larva (6-dpf). At 60-dpf juveniles, the and mRNA levels of LED-exposed individuals were higher than those of light-shielded ones, whereas at 40-dpf and 50-dpf juveniles, the mRNA expression was higher in the light-shielded condition (<0.05). In the pigmented juveniles (90-dpf), the and mRNA levels tended to show higher levels in red individuals than those in green ones, but there was a conversely higher level of mRNA in green larva. examination of and mRNAs in light-shielded 6-dpf larva revealed that both genes are mainly expressed in the internal organs compared to the body surface. Together, these results may provide insights into the differential gene expression of , , and during pigmentation process of the sea cucumber.