文獻來源: Ferguson LC, Jiggins CD. 2009. Shared and divergent expression domains on mimetic Heliconius wings. Evolution & Development 11(5): 498-512. [摘要網址]簡介
毒蝶屬(Heliconius)為擬態生物學中穆氏擬態最具代表性的例子，自1879年穆氏擬態發表後，即吸引生物學家從多許多生物議題探討此龐大擬態群的產生，如行為學、演化學、化學生物學、群聚生態學，至近代的分子生物學、發育生物學等，但該擬態群的演化歷程仍然有許多的疑問未解。本篇文章從發育生物學的角度出發，嘗試以兩種毒蝶屬的物種，H. erato與H. melpomene，探索其相似翅紋的發育來源。作者觀察蛹發育時期時有關翅紋色素的基因發育表現，發現在兩個物種中，有關所有有關朱紅色色素形成的基因皆有關連，但其表現的形式有顯著的差異。兩個未在H. erato中研究的基因，scarlet與kf，增強H. melpomene的猩紅色素在翅紋中的呈現，可能暗示此兩種基因也在擬態的其他成員中參與翅紋的調控。
Abstract
Heliconius butterfly wing patterns show repeated convergence between species and have adaptive value in mimicry and mate choice, offering an opportunity to connect adaptive changes in phenotype with their underlying genotypes. Here we study forewing ommochrome pigmentation in Heliconius melpomene. We clone two new ommochrome pathway genes for the Lepidoptera, karmoisin and kynurenine formamidase (kf ), and analyze the expression patterns of all known ommochrome genes across pupal wing development. In combination with published work, this generates the first comparative gene expression data for the co-mimics Heliconius erato and H. melpomene. In both species cinnabar expression correlates with the forewing band, but the expression pattern of vermillion differs significantly between the mimics. This demonstrates that both shared and divergent expression patterns are associated with mimetic phenotypes between Heliconius species. Two genes not studied in H. erato, scarlet and possibly kf, also show enhanced expression in the forewing band of H. melpomene, implying co-ordinated upregulation of several members of this biosynthetic pathway during pattern formation.
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