Drosophila antimicrobial peptides
Drosophila antimicrobial peptides
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DOI：
10.4267/10608/1192
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发表时间：
1999-01-01
影响因子：
0.7
通讯作者：
Bulet, P
中科院分区：
文献类型：
--
作者：
Bulet, P
昆虫对微生物感染有显著的抵抗力。它们的宿主防御依赖于细胞和体液反应。细胞机制涉及吞噬作用和病原体的封装。体液应答包括激活蛋白水解级联反应，导致凝血和黑化，以及合成在血淋巴中起作用的抗微生物肽以对抗感染。近年来，黑腹果蝇已成为研究昆虫免疫分子机制的理想模型。在果蝇中，已经鉴定了七种不同的分子加上同种型，抗菌肽天蚕素、防御素、drosocin、diptericin和attacins，抗真菌的drosomycin和metchnikowins，它们对细菌和真菌都有活性。这些分子属于昆虫抗菌肽的4个家族，即（1）形成螺旋的肽，（2）富含半胱氨酸的肽，（3）富含脯氨酸的肽和（4）具有高含量甘氨酸残基的肽。这些抗生素共同具有正净电荷，这使得它们能够与微生物的膜相互作用。nisms。在实验感染的反应中，由脂肪体（哺乳动物肝脏的功能等价物）合成的果蝇抗菌肽的总体血淋巴浓度达到200 μ M的值，其中一半是占了drosomycin。最近的研究表明，果蝇系统性免疫反应中抗菌肽基因表达的调控与脊椎动物的先天免疫有惊人的相似之处。
Insects are remarkably resistant to microbial infections. Their host defense relies on cellular and humoral responses. The cellular mechanism involves phagocytosis and encapsulation of pathogens. The humoral response includes activation of proteolytic cascades leading to coagulation and melanization and synthesis of antimicrobial pep tides acting in the hemolymph to fight the infection. Over the last years, Drosophila melanogaster has become a favourite model to investigate the molecular mechanisms of insect immunity. In Drosophila seven distinct molecules plus isoforms have been characterized, the antibacterial peptides cecropins, defensin, drosocin, diptericin and attacins, the antifungal drosomycin and metchnikowins which are active against both bacteria and fungi. These molecules belong to the 4 families of insect antimicrobial peptides namely (1) peptides forming a helices, (2) cysteine-rich peptides, (3) proline-rich peptides and (4) peptides with a high content in glycine residues. These antibiotics have in common a positive net charge which allows them to interact with the membrane of the microorganisms. nisms. In response to an experimental infection, the overall hemolymph concentration of Drosophila antimicrobial peptides synthesized by the fat body (a functional equivalent of the mammalian liver) reaches the value of 200 mu M, half of which is accounted for drosomycin. Recent studies on the regulation of the antimicrobial peptide gene expression during the systemic Drosophila immune response has revealed striking similarities with vertebrate innate immunity.