To investigate the involvement of prepro-proopiomelanocortins (POMCs) with hypermelanosi on the blind side of olive flounder, Paralichthys olivaceus, we surveyed tissue sites in which the three POMCs genes are expressed, and compared pituitary-ofPOMCs (ofPOMC-Ⅰ, Ⅱ and Ⅲ) mRNA activities between the normal and the hypermelano flounders. For the studies, we refereed to the information of ofPOMC-Ⅰ and Ⅱ genes in NCBI, but we try to newly discover ofPOMC-Ⅲ sequence. At first, we cloned and characterized cDNA encoding its ofPOMC-Ⅲ from the pituitary of olive flounder The ofPOMC-Ⅲ cDNA consists of 1,258 bp nucleotides and 7 peptides (Signal peptide, N-POMC, α-MSH, CLIP, N-β-LPH, β-MSH and β-END-like peptide) encoded in 231 amino acids. In the test of tissue distribution of ofPOMCs in olive flounder, we found that ofPOMC-Ⅰ is expressed in pitutary only, but ofPOMC-Ⅱ and Ⅲ are expressed in all tissues examined. In the comparison of ofPOMCs mRNA expression between the normal and the hypermelano fish, expression of ofPOMC-Ⅰ, Ⅱ mRNA was significantly higher in the hypermelano group than in normal group, but ofPOMC-Ⅲ was not significantly different between two groups.

• Hyo-Chan Kim(West Sea Fisheries Research Institute, NFRDI)
• Duk-Young Kang(West Sea Fisheries Research Institute, NFRDI)