Molecular and structural characterization of photoreceptor cells in Lophotrochozoa in order to utilise the photosensitive system as comparative character for inferring metazoan interrelationships. II. Eyes and photoreceptors of Mollusca and Platyhelminthe

我们的项目旨在研究软体动物、线虫、腕足动物和扁虫中光感受器细胞和眼睛的分子和形态特征，并将它们相互比较，并与环节动物的光敏系统进行比较。因此，我们将确定和探索有用的特征来解决Lophotrochozoa的系统发育问题，Lophotrochozoa是海洋无脊椎动物群体中一个大型且未定义的分类群。我们计划研究光色素、遮蔽色素、特定的转录因子以及光感受器、色素和支持细胞的超微结构，这些细胞构成了不同的光敏器官(眼细胞、眼睛和无色素器官)。选定的物种包括腹足类、代表软体动物的多足类、代表扁虫的三叶虫和螺类、代表新纪元的古潜水虫和异潜水虫，以及腕足类物种，以补充我们之前的研究。我们将着重于鉴定不同群体中的同源和近亲视蛋白，以及不同的视蛋白亚家族如何分布到不同类型的光感受器细胞，如纤毛和横纹感光器。这将允许识别光感受器和眼睛进化的线条，跨越Lophotrochozoan的系统发育。

Our project aims at the combined molecular and morphological characterisation of photophotoreceptor cells and eyes in molluscs, nemerteans, brachiopods and flatworms, to compare these to each other and to photosensitive systems in annelids. We will thus identify and explore useful characters for resolving the phylogeny of the Lophotrochozoa, which is a large and illdefined taxon of marine invertebrate animal groups. We plan to investigate opsin photopigment, shading pigment, specifying transcription factors as well as the ultrastructure of photoreceptor, pigment and support cells that constitute the diverse light-sensitive organs (ocelli, eyes and unpigmented organs). Selected species include gastropods, polyplacophorans representing molluscs, triclades and proseriates representing flatworms, palaeonemerteans and heteronemerteans representing nemerteans, and a brachiopod species, to complement our previous studies. We will focus on the identification of orthologous and paralogous opsin photopigment in the various groups, and how the distinct subfamilies of opsins distribute to the different types of photoreceptor cells, such as cililary and rhabdomeric photoreceptors. This will allow identifying lines of photoreceptor and eye evolution across lophotrochozoan phylogeny.