Ookinete-induced midgut peroxidases detonate the time bomb in anopheline mosquitoes
Ookinete-induced midgut peroxidases detonate the time bomb in anopheline mosquitoes
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DOI：
10.1016/j.ibmb.2005.02.014
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发表时间：
2005-07-01
影响因子：
3.8
通讯作者：
Barillas-Mury, C
中科院分区：
文献类型：
--
作者：
Kumar, S;Barillas-Mury, C
先前对动合子迁移和介导中肠免疫防御反应的基因的细胞定位之间的时空关系的分析表明，为了生存，寄生虫必须在入侵细胞产生有毒化学物质（“炸弹”）之前完成入侵。最近的研究表明，动合子入侵诱导酪氨酸硝化作为一个两步反应，其中NOS诱导后，过氧化物酶活性的局部增加。过氧化物酶利用亚硝酸盐和过氧化氢作为底物，通过产生介导硝化的活性氮中间产物（例如二氧化氮）来引爆定时炸弹。有证据表明，过氧化物酶还在包括人类和植物在内的广泛的生物系统中介导对细菌、真菌和寄生虫的抗微生物应答。产生有毒化学物质的防御反应也可能对宿主有害，并经常导致细胞凋亡。两步硝化途径可能是一种古老的反应，因为它也在脊椎动物白细胞中被描述，并且可能进化为一种机制，以限制在涉及蛋白质硝化的防御反应期间产生的有毒产物。爱思唯尔有限公司出版
Previous analysis of the temporal-spatial relationship between ookinete migration and the cellular localization of genes mediating midgut immune defense responses suggested that, in order to survive, parasites must complete invasion before toxic chemicals ("a bomb") are generated by the invaded cell. Recent studies indicate that ookinete invasion induces tyrosine nitration as a two-step reaction, in which NOS induction is followed by a localized increase in peroxidase activity. Peroxidases utilize nitrite and hydrogen peroxide as substrates, and detonate the time bomb by generating reactive nitrogen intermediates, such as nitrogen dioxide, which mediate nitration. There is evidence that peroxidases also mediate antimicrobial responses to bacteria, fungi and parasites in a broad range of biological systems including humans and plants. Defense reactions that generate toxic chemicals are also potentially harmful to the host mounting the response and often results in apoptosis. The two-step nitration pathway is probably an ancient response, as it has also been described in vertebrate leukocytes and probably evolved as a mechanism to circumscribe the toxic products generated during defense responses involving protein nitration. Published by Elsevier Ltd.