Genome-wide identification of interleukin-17 (IL17) in common carp (Cyprinus carpio) and its expression following Aeromonas hydrophila infection
GENE
Authors: Dong, Chuanju; Kong, Shengnan; Zheng, Xianhu; Zhang, Jiangfan; Nie, Guoxing; Li, Xuejun; Xu, Peng
Abstract
Interleukin-17 (IL17) family cytokines are well known for having pro-inflammatory actions as important mediators of mucosal immune responses and are tightly regulated by various kinds of signals. However, most studies of IL17 genes have focused on mammals, and much less is known about IL17 genes in fish species. To better understand the scope and actions of the IL17 gene family in common carp, we characterized seven IL17 gene homologs from genomic and transcriptomic databases that could be classified into three subclasses according to different comparative genomic analyses. Phylogenetic analysis revealed that most IL17s are highly conserved, though recent gene duplication and gene loss events do exist. Through observation, we found that IL17D has undergone gene duplication in common carp and that all the IL17E genes were lost in vertebrates except mammals. The expression patterns of IL17 genes in common carp were examined during early developmental stages and in various healthy tissues, and the results indicated that most IL17 genes are ubiquitously expressed during early development and show particular tissue-specific expression in various healthy tissues, with relatively high levels in the spleen, liver, and kidney. To gain insights into the mucosal actions of inflammatory processes, the expression profiles of IL17 genes in gills from common carp were investigated after experimental challenge with Aeromonas hydrophila. After A. hydrophila infection, most IL17 genes were upregulated at 4 h postinfection in the gill and then gradually declined, while IL17A/F2 and IL17N were generally upregulated at 12 h postinfection, and IL17D2 maintained an increasing tendency. In contrast, IL17D showed the third phenomenon, rising expression, suggesting that immunogenes have different response strategies to bacterial invasion. Overall, the expression of IL17 in unstimulated tissues and toxicity attack test results demonstrated that these genes play critical roles under normal conditions and during bacterial infection. Moreover, this common carp IL17 gene family research provides a genomic resource for future studies on IL17 gene evolution, fish disease management and immune regulation.
The Prosurvival IKK-Related Kinase IKK epsilon Integrates LPS and IL17A Signaling Cascades to Promote Wnt-Dependent Tumor Development in the Intestine
CANCER RESEARCH
Authors: Goktuna, Serkan Ismail; Shostak, Kateryna; Chau, Tieu-Lan; Heukamp, Lukas C.; Hennuy, Benoit; Hong-Quan Duong; Ladang, Aurelie; Close, Pierre; Klevernic, Iva; Olivier, Fabrice; Florin, Alexandra; Ehx, Gregory; Baron, Frederic; Vandereyken, Maud; Rahmouni, Souad; Vereecke, Lars; van Loo, Geert; Buttner, Reinhard; Greten, Florian R.; Chariot, Alain
Abstract
Constitutive Wnt signaling promotes intestinal cell proliferation, but signals from the tumor microenvironment are also required to support cancer development. The role that signaling proteins play to establish a tumor microenvironment has not been extensively studied. Therefore, we assessed the role of the proinflammatory Ikk-related kinase Ikke in Wnt-driven tumor development. We found that Ikke was activated in intestinal tumors forming upon loss of the tumor suppressor Apc. Genetic ablation of Ikke in beta-catenin-driven models of intestinal cancer reduced tumor incidence and consequently extended survival. Mechanistically, we attributed the tumor-promoting effects of Ikk epsilon to limited TNF-dependent apoptosis in transformed intestinal epithelial cells. In addition, Ikk epsilon was also required for lipo-polysaccharide (LPS) and IL17A-induced activation of Akt, Mek1/2, Erk1/2, and Msk1. Accordingly, genes encoding proinflammatory cytokines, chemokines, and anti-microbial peptides were downregulated in Ikk epsilon-deficient tissues, subsequently affecting the recruitment of tumor-associated macrophages and IL17A synthesis. Further studies revealed that IL17A synergized with commensal bacteria to trigger Ikk epsilon phosphorylation in transformed intestinal epithelial cells, establishing a positive feedback loop to support tumor development. Therefore, TNF, LPS, and IL17A-dependent signaling pathways converge on Ikk epsilon to promote cell survival and to establish an inflammatory tumor microenvironment in the intestine upon constitutive Wnt activation. (C) 2016 AACR.