Plasticity and genetic basis of cichlid gill arch anatomy reveal novel roles for Hedgehog signaling

Teleost gill arches are exquisitely evolved to maximize foraging efficiency, and include structures for the capture, filtering, and processing of prey. While both plasticity and a genetic basis for gill arch traits have been noted, the relative contribution of genetics and the environment in shaping these structures remains poorly understood. East African cichlids are particularly useful in this line of study due to their highly diverse and plastic feeding apparatus. Here we explore the gene-by-environmental effects on cichlid GRs by rearing pure bred species and their F3 hybrids in different foraging environments. We find that anatomical differences between species are dependent on the environment. The genetic architecture of these traits is also largely distinct between foraging environments. We did, however, note a few genomic “hotspots” where multiple traits map to a common region. One of these, for GR number across multiple arches, maps to the ptch1 locus, a key component of the He...

硬骨鱼鳃弓（Teleost gill arches）经精妙演化以最大化觅食效率，其结构具备捕获、过滤与处理猎物的功能。尽管已有研究表明鳃弓性状兼具表型可塑性与遗传基础，但遗传学与环境在塑造这些结构中的相对贡献仍有待深入解析。东非丽鱼（East African cichlids）拥有高度多样且可塑性强的摄食器官，是此类研究的理想实验体系。本研究通过将纯种物种及其F3代杂交种饲养于不同觅食环境中，探究了丽鱼鳃弓（GRs, gill arches）的基因-环境互作效应。研究结果显示，物种间的解剖学差异依赖于环境条件；这些性状的遗传架构在不同觅食环境中也存在显著差异。不过，本研究仍观测到数个基因组"热点区域"，即多个性状定位至同一基因组区域的位点。其中一个与多鳃弓鳃弓数量相关的位点，定位至ptch1基因座（ptch1 locus），该位点是He...的关键组成部分。