日本血吸虫全基因组测序完成

血吸虫是一种可引起人类血吸虫病的寄生虫,在中国乃至世界造成了极大的危害,其种类主要包括流行于亚洲的日本血吸虫和流行于非洲、南美洲的曼氏血吸虫。我们所在的日本血吸虫基因组测序和功能分析协作组完成了对日本血吸虫的全基因组测序。结果显示,日本血吸虫基因组序列由近4亿个碱基组成,含有大量的重复序列(占基因组41%)。我们从中共识别出编码基因13469个,其中有首次发现的与血吸虫感染宿主密切相关的弹力蛋白酶(elastase)基因。在与具有同等大小基因组的非寄生生物比较中,我们发现虽然基因数量相似,但其功能基因的组成却有较大差别:日本血吸虫一方面丢失了很多与营养代谢相关的基因,如脂肪酸、氨基酸、胆固醇和性激素合成基因等,这些营养物质必须从哺乳动物宿主获得;另一方面,扩充了许多有利于蛋白消化的酶类基因家族的成员。这一变化充分体现了血吸虫适应寄生生活,与宿主协同进化的重要特性。血吸虫基因组学研究成果加深了我们对血吸虫生物学特点、分子寄生虫学、分子进化以及与宿主的相互作用等方面的认识。同时,也为血吸虫病的诊断、疫苗研制和新药研究奠定了重要基础。

The Schistosoma japonicum Genome Reveals Features of Host-Parasite Interplay

Schistosoma japonicum is a parasitic flatworm that causes human schistosomiasis,which is a significant cause of morbidity in China and the Philippines.Here we present a draft genomic sequence for the worm.The genome provides a global insight into the molecular architecture and host interaction of this complex metazoan pathogen,revealing that it can exploit host nutrients,neuroendocrine hormones and signalling pathways for growth,development and maturation.Having a complex nervous system and a well-developed sensory system,S.japonicum can accept stimulation of the corresponding ligands as a physiological response to different environments,such as fresh water or the tissues of its intermediate and mammalian hosts.Numerous proteases,including cercarial elastase,are implicated in mammalian skin penetration and haemoglobin degradation.The genomic information will serve as a valuable platform to facilitate development of new interventions for schistosomiasis control.