Abstract：
Entamoeba histolytica, an intestinal parasite of global significance, poses substantial health risks with its associated high morbidity and mortality rates. Despite the current repertoire of molecular tools for the study of gene function in, the regulatory mechanisms governing its pathogenicity remain largely unexplored. This knowledge gap underscores the need to elucidate key genetic determinants orchestrating cellular functions critical to its virulence. Previously, our group generated an avirulent strain, termed UG10, with the same genetic background as the HM1:IMSS strain. UG10 strain, despite showing normal expression levels of well-known virulence factors, was unable to perform in-vitro and in-vivo activities related to amoebic virulence. In this study, we aimed to uncover the genome-wide modifications that rendered the avirulent phenotype of the UG10 strain through whole-genome sequencing. As a complementary approach, we conducted Methylated DNA Immunoprecipitation coupled with sequencing (MeDIP-seq) analysis on both the highly virulent HM1:IMSS strain and the low-virulence UG10 strain to uncover the genome-wide methylation profile. These dual methodologies revealed two aspects of the UG10 avirulent strain. One is the random integration of fragments from the ribosomal gene cluster and tRNA genes, ranging from 120 to 400 bp; and secondly, a clear, enriched methylation profile in the coding and non-coding strand relative to the start codon sequence in genes encoding small GTPases, which is associated with the previously described avirulent phenotype. This study provides the foundation to explore other genetic and epigenetic regulatory circuitries in E. histolytica and novel targets to understand the pathogenic mechanism of this parasite.
摘要：
溶组织内阿米巴,一种具有全球意义的肠道寄生虫，其相关的高发病率和死亡率会带来巨大的健康风险。尽管目前有许多用于研究基因功能的分子工具，控制其致病性的调节机制在很大程度上仍未被探索。这种知识差距强调了需要阐明关键的遗传决定因素，以协调对其毒力至关重要的细胞功能。以前,我们小组产生了一种无毒菌株，称为UG10，与HM1：IMSS菌株具有相同的遗传背景。UG10菌株,尽管显示出众所周知的毒力因子的正常表达水平，无法进行与阿米巴毒力相关的体外和体内活动。在这项研究中,我们旨在通过全基因组测序揭示UG10菌株的无毒表型的全基因组修饰.作为一种补充方法，我们对高毒力HM1:IMSS株和低毒力UG10株进行了甲基化DNA免疫沉淀联合测序(MeDIP-seq)分析,以揭示全基因组甲基化谱.这些双重方法揭示了UG10无毒菌株的两个方面。一种是来自核糖体基因簇和tRNA基因的片段的随机整合，范围从120到400bp；其次，一个明确的,相对于编码小GTP酶的基因的起始密码子序列，编码和非编码链中的富集甲基化谱，这与先前描述的无毒表型有关。本研究为探索溶组织大肠杆菌的其他遗传和表观遗传调控机制奠定了基础，并为了解该寄生虫的致病机制提供了新的靶标。
