4种壳色蛤仔TYR基因的表达特性研究

TYR gene expression profiling in four shell color strains of Manila clam(Ruditapes philippinarum)

为了解色素控制基因与壳色的关系,本实验用荧光定量聚合酶链式反应(Polymerase Chain Reaction,PCR)技术分析了酪氨酸酶基因(Tyrosinase,TYR)在菲律宾蛤仔(Ruditapes philippinarum)4种壳色蛤仔和7种组织中的表达特性。结果表明,酪氨酸酶基因在鳃、外套膜、闭壳肌、性腺、内脏团、水管和唇瓣中均有表达,其中外套膜中表达量较高,其次为鳃,在闭壳肌中表达量最少。不同的酪氨酸酶基因在4种壳色的表达量不同,酪氨酸酶基因TYR2、TYR3、TYR6和TYR9在白斑马蛤中表达量居高,且与斑马蛤和白蛤差异显著(P<0.05)。TYR2、TYR6和TYR10在橙蛤中表达量最高,推测与橙色形成有关。TYR11在斑马蛤中表达量最高,且与白蛤和白斑马蛤差异显著(P<0.05),推测与背景色形成有关。系统发育分析结果表明,TYR3与马氏珠母贝(Pinctada martensii)同源性最高为64%。TYR10与加州双斑蛸(Octopus bimaculoides)同源性最高,为53%。与长牡蛎进化关系最近。

In order to understand the relationship between the pigment control gene and shell color,the expression characteristics of tyrosinase(TYR)in four selected strains of Manila clam(Orange,Zebra,White zebra,and White)were analyzed in relative quantification PCR.The results from gill,mantle,adductor muscle,gonad,visceral mass,siphon and palp tissue showed that the tyrosinase gene expression in mantle was higher than other tissues and least expressed in adductor muscle.All four shell color strains of Manila clam have different levels in the expression of tyrosinase gene.The high expression of TYR2,TYR3,TYR6 and TYR9 in the white zebra,while the white clam was significantly different(P<0.05).TYR2,TYR6 and TYR10 were the highest expression in Orange strain,suggesting it maybe related to the formation of orange shell color.While TYR11 was the highest expression in zebra clam,and was significantly different from white clams and white zebra clams(P<0.05),presumably related to the formation of background color.Phylogenetic analysis showed that the homology of TYR3 to Pinctada martensii was 64%.The highest homology of TYR10 to Octopus bimaculoides was 53%.It has recently been involved in the evolution of Crassostrea giga.