A Preliminary Study On The Molecular Mechanism Of Pigmentation In Pacific Oyster Crassostrea Gigas

Pacific oyster Crassostrea gigas is an important economic shellfish in China.Previous studies have found that the adductor muscle scar and the outer surface of the shell are different in color,which is mainly caused by the deposition of melanin,but the pigmentation patterns and mechanism still remains unknown in the Pacific oyster.In the preliminary work,the colors of the adductor muscle scar vs.the outer surface of the shell on the same side were compared.No relevance was found between the colors of the adductor muscle scars and the corresponding outer surface of the shells.The molecular mechanism of pigment deposition was studied by transcriptome sequencing and qRT-PCR techniques.In addition,the study analyzed the relationship between melanin deposition and soft-body weight and related physiological parameters The main results are as follows:1?Studies have shown that the oyster with black adductor muscle scar possess the larger soft-body weight and the corresponding adductor muscle has a stronger ability to inhibit hydroxyl radicals.We proposed a new point that the melanin could reduce the oxidative damage of the adductor muscle to increase the feeding time of oysters and ultimately accelerate the growth rate of oysters.2?After the transcriptomes of pigmented and unpigmented adductor muscles and mantles were studied by RNAseq and compared,it was found that the retinol metabolism pathway were likely to be involved in melanin deposition on the outer surface and the adductor muscle scar of the shell.3?Studies have shown that tyrosinase,retinal dehydrogenase and cytochrome P450 are closely related to melanin deposition in oyster,and that the different members of the tyrosinase,Retinal dehydrogenase and cytochrome P450 gene families could play a role in the independent pigmentation of different organs.The results provide some explanations for the molecular mechanism of the independence pigmentation between the outer surface and the adductor muscle scar of the shell.