abf-1 and abf-2, ASABF-type antimicrobial peptide genes in Caenorhabditis elegans
abf-1 and abf-2, ASABF-type antimicrobial peptide genes in Caenorhabditis elegans
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DOI：
10.1042/0264-6021:3610221
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发表时间：
2002-01-15
影响因子：
4.1
通讯作者：
Zhang, H
中科院分区：
文献类型：
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作者：
Kato, Y;Aizawa, T;Zhang, H
在秀丽隐杆线虫中鉴定出编码 ASABF（猪蛔虫抗菌因子）型抗菌肽 abf-1 和 abf-2 的两个基因。重组 ABF-2 对革兰氏阳性和谷粒阴性细菌以及酵母菌表现出有效的杀菌活性。通过免疫荧光染色和 gfp 融合基因（其中 GFP 对应于绿色荧光蛋白）的转基因分析估计的组织特异性分布表明 ABF-2 有助于咽部的表面防御。 abf-1 在保守位置包含单个内含子，表明 asabf 和 abf 起源于共同的祖先。 abf-1 和 abf-2 的转录物均被检测为两种不同的形式，即剪接前导序列 (SL)1 反式剪接，具有长 5'-非翻译区 (UTR) 和 SL-less，具有短 5'-UTR。检测到编码 ABF-1 和 ABF-2 的多顺反子前体 RNA，表明这些基因形成操纵子。提出了一种用于调节 abf 基因的“机会操纵子”模型，包括生成短的 SL-less 转录本。总之，由于抗菌肽，线虫应该具有免疫防御系统。线虫可以成为先天免疫的新模型。此外，将猪蛔虫的生化鉴定与线虫中的同源物狩猎相结合，应该是寻找快速进化的蛋白质的有效方法，例如线虫中的一些免疫相关分子。
Two genes encoding the ASABF (Ascaris suum antibacterial factor)-type antimicrobial peptide, abf-1 and abf-2, were identified in Caenorhabditis elegans. Recombinant ABF-2 exhibited potent microbicidal activity against Gram-positive and Grain-negative bacteria, and yeasts. The tissue-specific distribution estimated by immunofluorescence staining and transgenic analysis of a gfp fusion gene (where GFP corresponds to green fluorescent protein) suggested that ABF-2 contributes to surface defence in the pharynx. abf-1 contains a single intron at a conserved position, suggesting that asabf and abf originated from a common ancestor. Both transcripts for abf-1 and abf-2 were detected as two distinct forms, i.e. spliced leader (SL)1-trans-spliced with a long 5'-untranslated region (UTR) and SL-less with a short 5'-UTR. A polycistronic precursor RNA encoding ABF-1 and ABF-2 was detected, suggesting that these genes form an operon. An 'opportunistic operon' model for regulation of abf genes, including the generation of short SL-less transcripts, is proposed. In conclusion, C. elegans should have an immune defence system due to the antimicrobial peptides. C. elegans can be a novel model for innate immunity. Furthermore, the combination of biochemical identification in Ascaris suum and homologue hunting in C. elegans should be a powerful method of finding rapidly evolved proteins, such as some immune-related molecules in C. elegans.