Drosophila sex-peptide stimulates female innate immune system after mating via the Toll and Imd pathways
Drosophila sex-peptide stimulates female innate immune system after mating via the Toll and Imd pathways
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DOI：
10.1016/j.cub.2005.08.048
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发表时间：
2005-09-20
期刊：
影响因子：
9.2
通讯作者：
Kubli, E
中科院分区：
文献类型：
--
作者：
Peng, J;Zipperlen, P;Kubli, E
昆虫免疫防御主要基于体液因子，如直接杀死病原体的抗菌肽 (AMP) [1] 或涉及血细胞吞噬和封装的细胞过程 [2]。在果蝇中，Toll 途径（由真菌和革兰氏阳性菌激活）和 lmd 途径（由革兰氏阴性菌激活）导致 AMP 的合成 [3]。但 AMP 基因也可以在没有致病性挑战的情况下受到调节，例如通过衰老、昼夜节律和交配 [4-8]。在这里，我们发现 AMP 基因在交配雌性中差异表达。 Metchnikowin (Mtk) 表达在交配后的前 6 小时内受到强烈刺激。性肽 (SP) 是交配过程中转移的雄性精液肽，是引发 Mtk 和其他 AMP 基因转录的主要因子。 SP 诱导 Mtk 需要这两种途径。此外，SP 通过 Toll（卓霉素）和 Imd（敌蝶霉素）途径诱导额外的 AMP 基因。 SP 影响基因 spatzle 处或上游的 Toll 途径，以及基因 imd 处或上游的 Imd 途径。交配可能会对雌性造成身体伤害，并且病原体可能会传播[9]。因此，交配时 SP 对 AMP 转录的内源性刺激可能被认为是遭遇假定的免疫原性攻击的预防步骤。
Insect immune defense is mainly based on humoral factors like antimicrobial peptides (AMPs) that kill the pathogens directly [1] or on cellular processes involving phagocytosis and encapsulation by hemocytes [2]. In Drosophila, the Toll pathway (activated by fungi and gram-positive bacteria) and the lmd pathway (activated by gram-negative bacteria) lead to the synthesis of AMPs [3]. But AMP genes are also regulated without pathogenic challenge, e.g., by aging, circadian rhythms, and mating [4-8]. Here, we show that AMP genes are differentially expressed in mated females. Metchnikowin (Mtk) expression is strongly stimulated in the first 6 hr after mating. Sex-peptide (SP), a male seminal peptide transferred during copulation, is the major agent eliciting transcription of Mtk and of other AMP genes. Both pathways are needed for Mtk induction by SP. Furthermore, SP induces additional AMP genes via the Toll (Drosomycin) and the Imd (Diptericin) pathways. SP affects the Toll pathway at or upstream of the gene spatzle, the Imd pathway at or upstream of the gene imd. Mating may physically damage females and pathogens may be transferred [9]. Thus, endogenous stimulation of AMP transcription by SP at mating might be considered as a preventive step to encounter putative immunogenic attacks.