Evolutionary Dynamics of Structural Variation at a Key Locus for Color Pattern Diversification in Cichlid Fishes
Evolutionary Dynamics of Structural Variation at a Key Locus for Color Pattern Diversification in Cichlid Fishes
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丽鱼科鱼类颜色图案多样化关键位点结构变异的进化动力学
DOI：
10.1093/gbe/evz261
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发表时间：
2019
影响因子：
3.3
通讯作者：
Claudius F
中科院分区：
文献类型：
--
作者：
Kratochwil;Claudius F
非洲慈鲷鱼的颜色模式变化很大。尽管系统发育分析在30年前就表明，许多颜色模式在这些适应性辐射中反复进化，但直到最近，我们才开始了解颜色变化的基因组基础。水平条纹图案的进化和丢失几次独立的适应性辐射的维多利亚湖，马拉维和坦噶尼喀和agouti相关肽2（agrp 2/asip 2b）的监管演变已经与这种表型不稳定的性状。在这里，我们询问agrp 2基因座是否表现出促进颜色模式差异的特殊特征。基于比较基因组分析，我们发现了几个最近的重复，插入和缺失。有趣的是，其中一个事件导致agrp 2最后一个外显子的串联重复。这种复制可能发生在8-12 Ma开始的东非辐射之前，在任何辐射中都不固定，甚至在某些物种中也存在差异。此外，我们还观察到拷贝数的变化（2至5个拷贝）和重复的二次丢失，说明在这个位点可能促进agrp 2功能分化的令人惊讶的动态。我们的工作表明，这种情况下的外显子重复是一个被忽视的机制，可能涉及重复进化和多样化，值得更多的关注。
Color patterns in African cichlid fishes vary spectacularly. Although phylogenetic analysis showed already 30 years ago that many color patterns evolved repeatedly in these adaptive radiations, only recently have we begun to understand the genomic basis of color variation. Horizontal stripe patterns evolved and were lost several times independently across the adaptive radiations of Lake Victoria, Malawi, and Tanganyika and regulatory evolution ofagouti-related peptide 2(agrp2/asip2b) has been linked to this phenotypically labile trait. Here, we asked whether theagrp2locus exhibits particular characteristics that facilitate divergence in color patterns. Based on comparative genomic analyses, we discovered several recent duplications, insertions, and deletions. Interestingly, one of these events resulted in a tandem duplication of the last exon ofagrp2. The duplication likely precedes the East African radiations that started 8–12 Ma, is not fixed within any of the radiations, and is found to vary even within some species. Moreover, we also observed variation in copy number (two to five copies) and secondary loss of the duplication, illustrating a surprising dynamic at this locus that possibly promoted functional divergence ofagrp2. Our work suggests that such instances of exon duplications are a neglected mechanism potentially involved in the repeated evolution and diversification that deserves more attention.
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影响因子：
3.7
作者：
Fan S;Meyer A
通讯作者：
Meyer A
脆弱的DNA有助于重复进化
影响因子：
12.3
作者：
Kratochwil;Claudius F.;Axel Meyer
通讯作者：
Axel Meyer
评估年轻和年老丽鱼适应性辐射复制生态形态中的基因组分歧和平行性
影响因子：
4.9
作者：
M. McGee;R. Neches;O. Seehausen
通讯作者：
O. Seehausen
影响因子：
2
作者：
Kratochwil;Claudius F.
通讯作者：
Claudius F.
影响因子：
10.7
作者：
Kosakovsky Pond, Sergei L.;Posada, David;Frost, Simon D. W.
通讯作者：
Frost, Simon D. W.