Identification and partial characterisation of new members of the Ixodes ricinus defensin family
Identification and partial characterisation of new members of the Ixodes ricinus defensin family
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DOI：
10.1016/j.gene.2014.03.002
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发表时间：
2014-05-01
期刊：
影响因子：
3.5
通讯作者：
Grubhoffer, Libor
中科院分区：
文献类型：
--
作者：
Tonk, Miray;Cabezas-Cruz, Alejandro;Grubhoffer, Libor
硬蜱（硬蜱）是欧洲最常见的蜱种。蓖麻是影响人类和动物的疾病的病原体的载体，所述疾病包括蜱传脑炎、疏螺旋体病、蜱传热和巴贝虫病。先天免疫系统为蜱提供了相当有效的防御，以抵御某些病原微生物侵入蜱体内或通过血餐的情况。抗微生物肽（AMP）构成蜱免疫系统的重要特征。防御素是一类众所周知的AMP。已报道在几种蜱物种中存在防御素蛋白质家族的成员。到目前为止，只有两个防御素已被确定从I。蓖麻。在这项研究中，我们报告了六个新的推定防御素的鉴定。蓖麻在基因组和转录水平。在基因组水平上，它们显示出差异，其中一个是无内含子的，而另一些包含两个内含子。确定了这些分子在唾液腺、中肠、卵巢、马氏管、血淋巴和蜱细胞系IRE/CTVM 19中的表达模式。其中一些是组织特异性的，而另一些似乎是无处不在的。分子和系统发育分析表明，这些新成员属于I.蓖麻防御素家族在遗传和结构上不同;然而，半胱氨酸模式在家族成员中高度保守。最后，抗菌肽预测工具被用来预测我们的防御素推定的抗菌活性。它们显示出主要针对革兰氏阳性菌的推定的抗微生物活性。这项研究显示了防御素家族在蜱I中的多样性。蓖麻。(C)2014爱思唯尔有限公司版权所有。
The hard-bodied tick Ixodes ricinus (castor bean tick) is the most common tick species in Europe.I. ricinus is a vector of the causative agents of diseases that affect humans and animals including tick-borne encephalitis, borreliosis, tick-borne fever and babesiosis. The innate immune system provides ticks with quite an efficient defence against some pathogenic microorganisms in the event of their penetration into the tick body or through the blood meal. Antimicrobial peptides (AMPs) constitute an important feature of the tick immune system. Defensins are a well-known class of AMPs. Members of the defensin family of proteins have been reported in several tick species. So far, only two defensins had been identified from I. ricinus. In this study, we report the identification of six novel putative defensins from I. ricinus at the genomic and transcriptional levels. At the genomic level they show differences with one being intronless, while others contain two introns. The expression pattern of these molecules in the salivary glands, midgut, ovary, Malpighian tubules, haemolymph and the tick cell line IRE/CTVM19 was determined. Some of them are tissue specific while others seem to be ubiquitous. Molecular and phylogenetic analyses show that these novel members of the I. ricinus defensin family differ phylogenetically and structurally; nevertheless, the cysteine pattern is highly conserved among the family members. Finally, antimicrobial-peptide prediction tools were used to predict putative antimicrobial activity of our defensins. They show putative antimicrobial activity mainly against Gram-positive bacteria. This study displays the diversity of the defensin family in the tick I. ricinus. (C) 2014 Elsevier B.V. All rights reserved.