Genomic analysis of the morphologically simplified endoparasitic crustacean Sacculina carcini

一些节肢动物进化为体内寄生虫，并在身体形状和解剖结构上显示出巨大的变化，通常几乎不像节肢动物。寄生的藤壶Sacculina carcini（甲壳纲：根头纲）是由于内寄生生活方式而进化转型的一个突出例子。成虫没有任何节肢动物亲属的迹象：节肢动物通常存在的分节，附属物和大部分内部器官完全缺失。成体分为两部分：一部分是在宿主体腔内生长的小根网络，另一部分是临时的繁殖囊，承载性腺并保持第一个幼虫阶段。在形态学和生活史方面有很好的研究记录，但对根头类物种的基因组几乎一无所知。拟议的项目旨在更好地了解这种极端形态改变的遗传和基因组基础。基于基因组和转录组数据的初步数据集，我们专注于完成癌囊藻的基因组。以及幼虫、小根和繁殖囊的转录组学特征。在比较其他节肢动物基因组的标准剧目和一个新的调查基因组数据集的非寄生藤壶藤壶amphitrite，我们将展示哪些基因组转换伴随着形态简化。基因内容以及监管效果将进行比较，以更好地了解基因组水平上的进化转化。一个主要的焦点是存在于基因组中并在发育阶段和器官中活跃的转录因子的库。转录组学概况幼虫和成人组织也将进行比较，以非寄生的相对，藤壶藤壶amphitrite获得更深入的了解形态变化的进化过程和寄生的开关。

A few arthropods evolved towards an endoparasites and show a dramatic change in body shape and anatomy, often barely resembling arthropods at all. The parasitic barnacle Sacculina carcini (Crustacea: Rhizocephala) is one prominent example in evolutionary transformation due to an endoparasitic lifestyle. The adults show no sign of their arthropod kin: segmentation, appendages and most of the internal organs usually found in arthropods are completely missing. The adult body is divided into two parts: a network of rootlets growing in the body cavity of the crab hosts and a temporary breeding sac, bearing gonads and keeping first larval stages. There is a good record of studies on morphology and life cycle, but almost nothing is known about the genome of rhizocephalan species. The proposed project aims to get a better understanding about the genetic and genomic foundations of this extreme modification of morphology. Building on preliminary datasets of genomic and transcriptomic data, we focus on the finishing of the genome of Sacculina carcini. and transcriptomic characterisation of larvae, rootlets and breeding sac. In a comparison to the standard repertoire of other arthropod genomes and a new survey genomes dataset of the non-parasitic barnacle Balanus amphitrite, we will show which genomic transformations accompany the morphological simplification. Gene content as well as regulatory effects will be compared to get a better understanding of evolutionary transformations on the genomic level. One main focus is the repertoire of transcription factors present in the genome and active in developmental stages and organs. Transcriptomic profiles larva and adult tissues will as well be compared to a non-parasitic relative, the barnacle Balanus amphitrite to gain deeper insight into the evolutionary processes of morphological change and the switch to parasitism.