A nuclear factor of high mobility group box protein in Toxoplasma gondii.
A nuclear factor of high mobility group box protein in Toxoplasma gondii.
复制标题
弓形虫高迁移率族盒蛋白的核因子
DOI：
10.1371/journal.pone.0111993
复制
发表时间：
2014
期刊：
影响因子：
3.7
通讯作者：
Liu Q
中科院分区：
文献类型：
--
作者：
Wang H;Lei T;Liu J;Li M;Nan H;Liu Q
高迁移率族蛋白1（HMGB 1）是一种核因子，通常结合DNA并调节多细胞生物中的基因表达。在弓形虫（一种专性细胞内原生动物病原体）基因组中预测了三种HMGB 1直系同源物，称为TgHMGB 1a、B和c。系统发育和生物信息学分析表明，这些蛋白都含有一个HMG盒，并在三种基因型中共享。我们克隆了TgHMGB 1a，一个33.9 kDa的蛋白，可以刺激巨噬细胞释放TNF-α，我们证明了TgHMGB 1a结合扭曲的DNA结构，如十字形DNA在电泳迁移率变动分析（EMSA）。免疫荧光检测表明，TgHMGB 1a主要集中在胞内速殖子的胞核内，但在胞质内有大量的TgHMGB 1a，而在胞外则有大量的TgHMGB 1a。TgHMGB 1 a B box缺失后，转基因小鼠的表型没有明显变化，而过表达TgHMGB 1 a的转基因小鼠细胞内生长缓慢，并导致小鼠延迟死亡。进一步的定量RT-PCR分析表明，当TgHMGB 1 a过表达时，包括毒力因子在内的许多重要基因的表达水平增加，但在TgHMGB 1 a B box缺失的转基因小鼠中没有观察到明显变化。我们的研究结果表明，TgHMGB 1a确实是一个核蛋白，维持HMG盒结构的功能，是一个潜在的促炎因子在弓形虫感染。进一步阐明TgHMGB 1的功能将增加我们对转录调控和寄生虫毒力的认识，并可能为T.弓形虫感染
High mobility group box 1 (HMGB1) is a nuclear factor that usually binds DNA and modulates gene expression in multicellular organisms. Three HMGB1 orthologs were predicted in the genome of Toxoplasma gondii, an obligate intracellular protozoan pathogen, termed TgHMGB1a, b and c. Phylogenetic and bioinformatic analyses indicated that these proteins all contain a single HMG box and which shared in three genotypes. We cloned TgHMGB1a, a 33.9 kDa protein that can stimulates macrophages to release TNF-α, and, we demonstrated that the TgHMGB1a binds distorted DNA structures such as cruciform DNA in electrophoretic mobility shift assays (EMSA). Immunofluorescence assay indicated TgHMGB1a concentrated in the nucleus of intracellular tachyzoites but translocated into the cytoplasm while the parasites release to extracellular. There were no significant phenotypic changes when the TgHMGB1a B box was deleted, while transgenic parasites that overexpressed TgHMGB1a showed slower intracellular growth and caused delayed death in mouse, further quantitative RT-PCR analyses showed that the expression levels of many important genes, including virulence factors, increased when TgHMGB1a was overexpressed, but no significant changes were observed in TgHMGB1a B box-deficient parasites. Our findings demonstrated that TgHMGB1a is indeed a nuclear protein that maintains HMG box architectural functions and is a potential proinflammatory factor during the T.gondii infection. Further studies that clarify the functions of TgHMGB1s will increase our knowledge of transcriptional regulation and parasite virulence, and might provide new insight into host–parasite interactions for T. gondii infection.
登录
查看更多内容
影响因子：
9.6
作者：
Melo, Mariane B.;Jensen, Kirk D. C.;Saeij, Jeroen P. J.
通讯作者：
Saeij, Jeroen P. J.
影响因子：
4
作者：
Dubey, JP
通讯作者：
Dubey, JP
影响因子：
2.9
作者：
Knapp, S;Müller, S;Musco, G
通讯作者：
Musco, G
影响因子：
1.9
作者：
Kumar, Krishan;Singal, Ankita;Chauhan, Virander S.
通讯作者：
Chauhan, Virander S.
影响因子：
--
作者：
Abhyankar, Mayuresh M.;Hochreiter, Amelia E.;Gilchrist, Carol A.
通讯作者：
Gilchrist, Carol A.