Gryllus bimaculatus transcriptomic assembly

Transcriptome assembly from: <b><br></b><b>Striking parallels between dorsoventral patterning in <i>Drosophila</i> and <i>Gryllus</i> reveal a complex evolutionary history behind a model gene regulatory network</b><b><br></b><b>Pechmann et al, 2021<br></b><b><br></b> <b> </b> <b>Abstract</b> Dorsoventral pattering relies on Toll and BMP signalling in all insects studied so far, with variations in the relative contributions of both pathways. <i>Drosophila</i> and the beetle <i>Tribolium</i> share extensive dependence on Toll, while representatives of more distantly related lineages like the wasp <i>Nasonia</i> and bug<i> Oncopeltus</i> rely more strongly on BMP signalling. Here, we show that in the cricket <i>Gryllus bimaculatus</i>, an evolutionarily distant outgroup,<i> </i>Toll has, like in <i>Drosophila</i>, a direct patterning role for the ventral half of the embryo. In addition Toll polarizes BMP signalling, although this does not involve the conserved BMP inhibitor Sog/Chordin. Finally, Toll activation relies on ovarian patterning mechanisms with striking similarity to <i>Drosophila. </i>Our data suggest two surprising hypotheses: 1) that Toll’s patterning function in <i>Gryllus</i> and <i>Drosophila</i> is the result of convergent evolution or 2) a <i>Drosophila-like </i>system arose early in insect evolution, and was extensively altered in multiple independent lineages.<br>

转录组组装数据集来源于：<b><br></b><b>《果蝇与双斑蟋蟀背腹图式形成的惊人相似性揭示模式基因调控网络的复杂演化历史》</b><b><br></b><b>Pechmann等，2021年</b><b><br></b><b> </b><b>摘要</b> 背腹图式形成依赖于当前已研究的所有昆虫的Toll与BMP（骨形态发生蛋白，Bone Morphogenetic Protein）信号通路，且两条通路的相对贡献存在变异。果蝇（Drosophila）与甲虫赤拟谷盗（Tribolium）均高度依赖Toll通路；而亲缘关系更远的类群，如纳森小蜂（Nasonia）与长蝽（Oncopeltus）则更依赖BMP信号通路。本研究表明，在演化上属于远缘外类群的双斑蟋蟀（Gryllus bimaculatus）中，Toll与果蝇类似，对胚胎腹侧区域具有直接的模式建成功能。此外，Toll可极化BMP信号通路，尽管该过程不涉及保守的BMP抑制剂Sog/Chordin。最后，Toll的激活依赖于卵巢模式建成机制，该机制与果蝇的同类机制具有惊人的相似性。本研究数据提出两项出人意料的假说：1）双斑蟋蟀与果蝇中Toll的模式建成功能是趋同演化的结果；2）类果蝇系统起源于昆虫演化早期，并在多个独立类群中发生了广泛改造。