Journal of Fishery Sciences of China (中国水产科学) 2013/20:6 PP.1139-1147
The numerous and diverse body color of fish was not only excellent materials to study the molecular mechanism of body color and body color inherence, body color evolution, and it was also an ideal model to diagnosis disease. Now, five basic and stable body color patterns have existed in Oujiang color common carp (Cyprinus carpio var. color), namely “Quanhong”, “Dahua”, “Mahua”, “Fenyu” and “Fenhua”, respectively. This fish can be a very good model and material for studying body color inheritance. At the melanin synthesis signaling pathway, skin color was regulated by a small group genes. Sox10 gene plays an important role in the formation of melanin, it regulates the birth, migration and differentiation of melanin. However, the effect of Sox10 gene on body color has not been reported. Four healthy lines of Oujiang color carp (“Quanhong”, “Dahua”, “Fenyu”, “Fenhua”) were collected from the provincial farm of the Zhejiang. Then the skin, muscle, eye, gill, kidney, swim bladder, heart, and liver were taken out, furthermore, the black skin and red skin were sampled separately of “Dahua”, the same with black skin and white skin of “fenhua”. Total RNA was extracted using Trizol, and reverse transcribed into the First-strand cDNA. Primers were designed by Primer5 program, and the right products were purified and sequenced. The obtained sequence was analyzed by Bioedit, Clustalw, Mega and other bioinformatics softwares. The total length of Sox10 gene cloned in Oujiang color common carp is 2 830 bp which contains 9 bp 5’ untranslated regions (UTR) and 1 375 bp 3’-UTR, and 1 446 bp open reading frame (ORF) encoding 481 amino acids. The phylogenetic analyses showed that there were 59%94% similarities in amino acid sequence with some of previously reported other species. RT-PCR analysis revealed that the gene was highly expressed in skin, muscle, eyes and swim bladder, weakly expressed in gill and heart and no expression were found in kidney and liver. Real-time PCR showed that the expression of the Sox10 gene in white skin (“Whole white” body color) was significantly higher than other color patterns (P<0.05), and the significantly lowest expression in black skin of “Fenhua” color pattern (P<0.05), but there were no significant difference in expression level among the other color patterns (P＞0.05). The results primarily indicated that the Sox10 gene is important in regulating body color variation in Oujiang color common carp. The information that obtained provides an important basis for conducting future studies on body color, and regulatory mechanisms in melanin synthesis signaling pathway, and provides an important theoretical basis for further research in body color selection during selective breeding in fish.