The blood-feeding behavior evolved multiple times in Insecta lineages and it represents an excellent opportunity to study patterns of convergent molecular evolution regarding this habit. In insects the expansion of some gene families is linked with blood-feeding behavior, but a wide study comparing the evolution of these gene families among different lineages is still missing. Here we gathered genomic data from six independently-evolved hematophagous lineages, aiming to identify convergent expansions and/or contractions of gene families in hematophagous lineages of insects. We found four rapidly evolving gene families shared by at least two hematophagous independently-evolved lineages, including a heat-shock and a chemosensory protein. On the expression of these four rapidly evolving gene families we found more genes expressed in mated individuals compared with virgin individuals in rapidly-expanded families and more genes expressed in non-blood-feeding individuals compared with blood-feeding individuals in rapidly-contracted families. Our results reveal a new set of candidate genes to be explored in further analysis to help the development of new strategies to deal with blood-feeding vectors and also presents a new perspective to study the evolution of hematophagy identifying convergent molecular patterns.

中文翻译：

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独立进化的吸血昆虫基因家族的扩张和收缩。


昆虫纲的吸血行为经历了多次进化，这为研究这种习惯的趋同分子进化模式提供了绝佳的机会。在昆虫中，一些基因家族的扩展与吸血行为有关，但仍缺乏比较这些基因家族在不同谱系之间进化的广泛研究。在这里，我们收集了来自六个独立进化的食血谱系的基因组数据，旨在识别昆虫食血谱系中基因家族的趋同扩张和/或收缩。我们发现至少两个独立进化的食血谱系共有四个快速进化的基因家族，其中包括热休克蛋白和化学感应蛋白。在这四个快速进化的基因家族的表达方面，我们发现，在快速扩张的家庭中，与未交配的个体相比，在交配个体中表达更多的基因；在快速收缩的家庭中，与吸血个体相比，在非吸血个体中表达更多的基因。我们的结果揭示了一组新的候选基因，有待进一步分析，以帮助开发处理吸血载体的新策略，并为研究噬血进化识别趋同分子模式提供了新的视角。