Data from: Using viromes to predict novel immune proteins in non-model organisms

Immunity is mostly studied in a few model organisms, leaving the majority of immune systems on the planet unexplored. To characterize the immune systems of non-model organisms alternative approaches are required. Viruses manipulate host cell biology through the expression of proteins that modulate the immune response. We hypothesized that metagenomic sequencing of viral communities would be useful to identify both known and unknown host immune proteins. To test this hypothesis, a mock human virome was generated and compared to the human proteome using tBLASTn, resulting in 36 proteins known to be involved in immunity. This same pipeline was then applied to reef-building coral, a non-model organism that currently lacks traditional molecular tools like transgenic animals, gene-editing capabilities, and in vitro cell cultures. Viromes isolated from corals and compared with the predicted coral proteome resulted in 2503 coral proteins, including many proteins involved with pathogen sensing and apoptosis. There were also 159 coral proteins predicted to be involved with coral immunity but currently lacking any functional annotation. The pipeline described here provides a novel method to rapidly predict host immune components that can be applied to virtually any system with the potential to discover novel immune proteins.

目前免疫学研究多集中于少数模式生物（model organism），全球绝大多数生物的免疫系统仍未得到探索。为解析非模式生物（non-model organism）的免疫系统，亟需开发替代研究方法。病毒通过表达调控宿主免疫应答的蛋白质，操纵宿主细胞的生命活动。我们提出假说：对病毒群落进行宏基因组测序（metagenomic sequencing），可用于识别宿主中已知与未知的免疫蛋白质。为验证该假说，我们构建了模拟人类病毒组（mock human virome），并通过tBLASTn将其与人类蛋白质组（proteome）进行比对，最终筛选出36种已知的免疫相关蛋白质。随后，我们将同一分析流程应用于造礁珊瑚（reef-building coral）——一种目前缺乏转基因动物（transgenic animals）、基因编辑技术及体外细胞培养（in vitro cell cultures）等传统分子研究工具的非模式生物。我们从珊瑚中分离得到病毒组，并将其与预测得到的珊瑚蛋白质组进行比对，最终获得2503种珊瑚蛋白质，其中包含大量参与病原体识别（pathogen sensing）与细胞凋亡（apoptosis）过程的蛋白质。此外，还有159种珊瑚蛋白质被预测参与珊瑚免疫过程，但目前尚无任何功能注释（functional annotation）信息。本研究提出的分析流程为快速预测宿主免疫组分提供了一种全新方法，几乎可应用于任何研究系统，有望发现全新的免疫蛋白质。