Pigmentary function and evolution of tyrp1 gene duplicates in fish
Pigmentary function and evolution of tyrp1 gene duplicates in fish
复制标题
DOI：
10.1111/j.1755-148x.2009.00614.x
复制
发表时间：
2009-12-01
影响因子：
4.3
通讯作者：
Schartl, Manfred
中科院分区：
文献类型：
--
作者：
Braasch, Ingo;Liedtke, Daniel;Schartl, Manfred
酪氨酸酶相关蛋白1(Tyrp1)在脊椎动物底部到四足动物中的功能尚未被研究。硬骨鱼有两个重复的Tyrp1基因。在这里，我们表明，硬骨Tyrp1重复以物种特有的方式分布在视网膜色素上皮(RPE)和黑素载体中的祖先基因表达。在青竹胚胎中，tyrp1a在RPE和黑素细胞中表达，而tyrp1b只在黑素细胞中表达。在斑马鱼胚胎中，Tyrp1 paralog在RPE和黑素载体中的表达重叠。单独敲除每个斑马鱼Tyrp1重复并不显示色素缺陷，但同时敲除两个Tyrp1基因会导致棕色而不是黑色真黑素的形成，并伴随着严重的黑色素体缺陷。我们的研究表明，Tyrp1缺陷脊椎动物的棕色黑素小体颜色是真黑素合成改变的结果。黑色真黑素的形成基本上依赖于Tyrp1的存在，它的一些功能很可能是从骨质脊椎动物的共同祖先那里保守下来的。
P>The function of the tyrosinase-related protein 1 (Tyrp1) has not yet been investigated in vertebrates basal to tetrapods. Teleost fishes have two duplicates of the tyrp1 gene. Here, we show that the teleost tyrp1 duplicates have distributed the ancestral gene expression in the retinal pigment epithelium (RPE) and melanophores in a species-specific manner. In medaka embryos, tyrp1a expression is found in the RPE and in melanophores while tyrp1b is only expressed in melanophores. In zebrafish embryos, expression of tyrp1 paralogs overlaps in the RPE and in melanophores. Knockdown of each zebrafish tyrp1 duplicate alone does not show pigmentary defects, but simultaneous knockdown of both tyrp1 genes results in the formation of brown instead of black eumelanin accompanied by severe melanosome defects. Our study suggests that the brown melanosome color in Tyrp1-deficient vertebrates is an effect of altered eumelanin synthesis. Black eumelanin formation essentially relies on the presence of Tyrp1 and some of its function is most likely conserved from the common ancestor of bony vertebrates.