酪氨酸酶(tyr)是一种75kD含铜酶，来源于胚胎神经峭细胞，是黑素代谢和儿茶酚胺的关键酶，广泛存在于动物、植物及真菌。
黑色素是一种生物色素，是酪胺酸经过一连串化学反应所形成，动物、植物与原生生物都有这种色素。黑色素通常是以聚合的方式存在。
近日，来自意大利的研究人员对后生动物的酪氨酸酶家族开展了一项深入的进化方面的分析。基于基因组测序，他们发现在所研究的生物中酪氨酸酶表现出差异性特征。有趣的是，在几乎所有被分析的类群，这些酪氨酸酶有着各自独立的进化方向。
酪氨酸酶相关蛋白(tyrp)来自于络氨酸酶，但是在其催化结构域却有着截然不同的残基。研究人员详细研究了玻璃海鞘的络氨酸酶及酪氨酸酶相关蛋白。而且，他们还确认了色素细胞系中与络氨酸酶表达有关的调节序列。
该研究增进了对酪氨酸酶基因家族的认识，有利于深入研究与色素细胞进化及发展有关的遗传元件。相关论文发表在4月20日的PLoS ONE。（生物谷Deepblue编译）
doi: 10.1371/journal.pone.0035731
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New Insights into the Evolution of Metazoan Tyrosinase Gene Family
Rosaria Esposito, Salvatore D'Aniello, Paola Squarzoni, Maria Rosa Pezzotti, Filomena Ristoratore, Antonietta Spagnuolo.
Tyrosinases, widely distributed among animals, plants and fungi, are involved in the biosynthesis of melanin, a pigment that has been exploited, in the course of evolution, to serve different functions.We conducted a deep evolutionary analysis of tyrosinase family amongst metazoa, thanks to the availability of new sequenced genomes, assessing that tyrosinases (tyr) represent a distinctive feature of all the organisms included in our study and, interestingly, they show an independent expansion in most of the analyzed phyla. Tyrosinase-related proteins (tyrp), which derive from tyr but show distinct key residues in the catalytic domain, constitute an invention of chordate lineage.In addition we here reported a detailed study of the expression territories of the ascidian Ciona intestinalis tyr and tyrps. Furthermore, we put efforts in the identification of the regulatory sequences responsible for their expression in pigment cell lineage.Collectively, the results reported here enlarge our knowledge about the tyrosinase gene family as valuable resource for understanding the genetic components involved in pigment cells evolution and development.
