Characterization of a subtilisin-like protease with apical localization from microsporidian Nosema bombycis
Characterization of a subtilisin-like protease with apical localization from microsporidian Nosema bombycis
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微孢子虫微孢子虫顶端定位的枯草杆菌蛋白酶样蛋白酶的表征
DOI：
10.1016/j.jip.2012.10.009
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发表时间：
2013-02-01
影响因子：
3.4
通讯作者：
Zhou, Zeyang
中科院分区：
文献类型：
--
作者：
Dang, Xiaoqun;Pan, Guoqing;Zhou, Zeyang
微孢子虫诺斯玛bombycis是导致pebrine的病原体，导致粒土文化的经济损失大大。对于寄生虫发育和发病机理至关重要的微孢子虫的蛋白酶知之甚少。在这里，我们确定了一个类似枯草蛋白的丝氨酸蛋白酶NBSLP1，该蛋白酶nbslp1包含抑制剂_I9和肽酶_s8域。 NBSLP1的催化结构域的三维建模表现出典型的三层夹层结构，其S1袋由Y-359代替。系统发育分析证实，微孢子虫的枯草素样丝氨酸蛋白酶分为两个进化枝：SLP1和SLP2，这表明最初的枯草菌素基因重复事件先于微孢子虫的形成。此外，RTPCR在Bombyx Mori感染的Midgut中检测到了NBSLP1的转录本。针对NBSLP1的抗体通过2D Western印迹识别前体和成熟酶。此外，间接免疫荧光测定法显示，NBSLP1主要定位在孢子的两个孢子上，这使得孢子看起来像“安全销”。值得注意的是，发芽后仅在孢子的顶端区域中检测到成熟的蛋白酶。这些研究表明，NBSLP1是微孢子虫中保守的枯草蛋白酶，并表明NBSLP1在极性管挤出过程中起重要作用。 （c）2012 Elsevier Inc.保留所有权利。
The microsporidian Nosema bombycis is the pathogen causing pebrine leading to heavy economic loss in sericulture. Little is known of the proteases of microsporidia that are important for both parasite development and pathogenesis. Here we identified a subtilisin-like serine protease NbSLP1 which contains an inhibitor_I9 and a peptidase_S8 domain. Three dimensional modeling of the catalytic domain of the NbSLP1 exhibited a typical 3-layer sandwich structure with S1 pocket substituted by Y-359. Phylogenetic analysis confirms that subtilisin-like serine proteases of microsporidia fall into two clades: SLP1 and SLP2, suggesting the initial subtilisin gene duplication events preceded microsporidia speciation. Furthermore, transcripts of Nbslp1 were detected in the midgut of Bombyx mori infection by N. bombycis by RTPCR. Antibodies against NbSLP1 recognized both the precursor and mature enzyme by 2D Western blotting. Besides, indirect immunofluorescence assay revealed that the NbSLP1 is mainly localized at the two poles of spore which make the spore look like "safety pins". Remarkably, the mature protease is only detected in the apical region of the spore after germination. These studies demonstrate that NbSLP1 is a conserved subtilisin protease in microsporidia and suggest that NbSLP1 play a significant role in polar tube extrusion process. (c) 2012 Elsevier Inc. All rights reserved.