title: Fas-associated factor 1 plays a negative regulatory role in the antibacterial immunity of Locusta migratoria.
abstract: Insect immune responses are precisely regulated to maintain immune balance. In this study, the Fas-associated factor 1 (FAF1) gene of Locusta migratoria manilensis, a homologue of the caspar gene that functions as a specific negative regulator in the antibacterial immunity pathway, was cloned. Gene expression analysis showed that FAF1 was expressed throughout the developmental stages and in all tested tissues, but its transcription levels varied significantly. Thus, FAF1 appears to be tightly regulated and is probably involved in multiple physiological processes. In addition, the antimicrobial peptide gene prolixicin was cloned and characterized. After bacterial challenge, prolixicin was rapidly up-regulated, whereas FAF1 was markedly down-regulated. This result was consistent with the observation that prolixicin was hyperactivated when FAF1 was suppressed by RNA interference. Moreover, after bacterial infection, the survival rate of FAF1-knockdown locusts was much higher than that of the wild-type. Taken together, these findings strongly suggest that FAF1 shares a similar function as caspar in Drosophila and may be involved in the negative regulation of antibacterial immunity in locusts.
authors: Institute of Entomology and Molecular Biology, College of Life Sciences, Chongqing Normal University, Chongqing, China.
authors: Z
authors: Z
authors: He
authors: P
authors: P
authors: Wang
authors: H
authors: H
authors: Shi
authors: F
authors: F
authors: Si
authors: Y
authors: Y
authors: Hao
authors: B
authors: B
authors: Chen
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D051017:Apoptosis Regulatory Proteins; D004625:Embryo, Nonmammalian / Q000378:metabolism; D004926:Escherichia coli; D005260:Female; D055785:Gene Knockdown Techniques; D019476:Insect Proteins / Q000378:metabolism*; D048188:Locusta migratoria / Q000276:immunology* / Q000378:metabolism; D008297:Male; D009758:Nymph / Q000378:metabolism; D034622:RNA Interference; D017422:Sequence Analysis, DNA
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D051017:Apoptosis Regulatory Proteins; C490780:FAF1 protein, human; D019476:Insect Proteins
keywords: Fas-associated factor 1; Locusta migratoria manilensis (Meyen); RNA interference; mRNA expression; negative immune regulation