帝王蝶迁飞的遗传机制被破解

The genetics of monarch butterfly migration and warning colouration

Shuai Zhan ^1,2,3, Wei Zhang², Kristjan Niitepo˜ld ^4,5, Jeremy Hsu⁴, Juan Ferna´ndez Haeger⁶, Myron P. Zalucki ⁷, Sonia Altizer ⁸,Jacobus C. de Roode ⁹, Steven M. Reppert ³ & Marcus R. Kronforst ²^{（1 Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China. 2 Department of Ecology & Evolution, University of Chicago, Chicago, Illinois 60637, USA.}^{3 Department of Neurobiology, University of Massachusetts Medical School, Worcester, Massachusetts 01605, USA.}^{4 Department of Biology, Stanford University, Stanford, California 94305, USA.}^{5 Department of Biosciences, University of Helsinki, FI-00014 Helsinki, Finland.}^{6 Departamento de Bota´nica, Ecologı´a y Fisiologı´a Vegetal, Universidad de Co´rdoba, 14071 Co´rdoba, Spain.}^{7 School of Biological Sciences, The University of Queensland, Brisbane, Queensland 4072, Australia.}^{8 Odum School of Ecology, University of Georgia, Athens, Georgia 30602, USA. 9 Department of Biology, Emory University, Atlanta, Georgia 30322, USA.）}

PNAS：揭示帝王蝶的迁徙策略

帝王蝶的迁飞路线图

帝王蝶迁飞是自然界中最为壮观的自然景象之一，北美地区的帝王蝶每年周而复始地完成数千公里的长途迁飞到达墨西哥进行越冬以适应温带地区的四季变化。然而，分布于热带地区的帝王蝶及其近缘种不具有迁飞特性。

研究人员从涵盖当今世界上主要的帝王蝶分布区域中，选取了包括迁飞型和非迁飞型的22个地理种群、5个近缘种的101只班蝶属蝴蝶进行了全基因组重测序和群体遗传学分析。该项研究表明现存的帝王蝶起源于北美地区，且祖先属于迁飞型，打破了先前认为包括鸟类等在内的迁飞物种均是热带起源，只在种群扩散到温带地区后才进化出迁飞行为的普遍认知。其次，帝王蝶被认为具有多套独特的代谢调节通路，如导航、生物节律、化学感应等来完成长距离迁飞这一复杂的生命现象。但研究人员利用群体遗传学分析对全基因组进行精细扫描发现，与飞行相关的肌肉发育进化是帝王蝶实现长距离迁飞的主要适应性选择。

詹帅研究组以鳞翅目、半翅目等昆虫为材料，通过基因组学、群体遗传学、生物信息学及功能基因组学等手段在微进化水平研究昆虫对环境的适应机制。该项研究获得了包括中国科学院项目在内的国内外多家单位的经费支持。

Figure 1: Global dispersal of the monarch butterfly.

a, Monarch butterfly sampling locations. b, Inferred phylogeny among Danaus species based on maximum likelihood analysis of 3,714 single-copy genes. c, Neighbour-joining phylogeny of all D. plexippusindividuals, based on genome-wide SNP data. ATL, Atlantic crossing; CEN, Central America (including south Florida); NOR, North America (including Mexico); PAC, Pacific crossing. d, Neighbour-joining consensus tree based on 1,000 bootstrap replicates. e, Principal component analysis (PCA) plots based on the first two principal components; inset shows separation between North America and south Florida. f, Genetic structure and individual ancestry; colours in each column represent ancestry proportion over range of population sizes K = 2–11. ABW, Aruba; AUS, Australia; BLZ, Belize; BMU, Bermuda; CRC, Costa Rica; ECU, Ecuador; ESP, Spain; FJI, Fiji; HI, Hawaii; MAR, Morocco; NZL, New Zealand; NCL, New Caledonia; PRI, Puerto Rico; PRT, Portugal; s.FL, south Florida; WSM, Samoa.

（来源：科技日报王春）

Abstract

The monarch butterfly, Danaus plexippus, is famous for its spectacular annual migration across North America, recent worldwide dispersal, and orange warning colouration. Despite decades of study and broad public interest, we know little about the genetic basis of these hallmark traits. Here we uncover the history of the monarch’s evolutionary origin and global dispersal, characterize the genes and pathways associated with migratory behaviour, and identify the discrete genetic basis of warning colouration by sequencing 101 Danaus genomes from around the globe. The results rewrite our understanding of this classic system, showing that D. plexippus was ancestrally migratory and dispersed out of North America to occupy its broad distribution. We find the strongest signatures of selection associated with migration centre on flight muscle function, resulting in greater flight efficiency among migratory monarchs, and that variation in monarch warning colouration is controlled by a single myosin gene not previously implicated in insect pigmentation.

链接地址：《Nature》doi:10.1038/nature13812