Chandler Jennifer C, Aizen Joseph, Elizur Abigail, Hollander-Cohen Lian, Battaglene Stephen C, Ventura Tomer
GeneCology Research Centre, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, 4 Locked Bag, Maroochydore, Queensland 4558, Australia.
The Robert H. Smith Faculty of Agriculture, Food and Environment, Department of Animal Sciences, The Hebrew University of Jerusalem, Rehovot 76100, Israel.
Gen Comp Endocrinol. 2015 May 1;215:76-87. doi: 10.1016/j.ygcen.2014.08.018. Epub 2014 Sep 9.
This study reports, for the first time in any of the commercially important decapod species, the identification of an insulin-like peptide (ILP), distinct from the androgenic gland hormone. Bioinformatics analysis of the de novo assembled spiny lobster, (Sagmariasus verreauxi) transcriptome, allowed identification of Sv-ILP1 as well as eight binding proteins. Binding proteins were termed as Sv-IGFBP, due to homology with the vertebrate insulin-like growth-factor binding protein and Sv-SIBD1-7, single insulin-binding domain protein (SIBD), similar to those identified in other invertebrate species. Sv-ILP1 was found to be expressed in the eyestalk, gonads and antennal gland of both sexes and to a lesser extent in male muscle, androgenic gland and hepatopancreas. The expression profiles of each binding protein were found to vary across tissues, with Sv-SIBD5, 6 and 7 showing higher expression in the gonad, demonstrated by PCR and digital gene expression. Further spatial investigations, using in-situ hybridisation, found Sv-ILP1 to be expressed in the neurosecretory cells of the thoracic ganglia, in keeping with the tissue expression of Drosophila ILP7 (DILP7). This correlative tissue expression, considered with the phylogenetic clustering of Sv-ILP1 and DILP7, suggests Sv-ILP1 to be a DILP7 orthologue. The broad expression of Sv-ILP1 strongly suggests that ILPs have a role beyond that of masculinisation in decapods. The function of these novel peptides may have application in enhancing aquaculture practices in the commercially important decapod species.
本研究首次在任何具有商业重要性的十足目物种中报道了一种与雄激素腺激素不同的胰岛素样肽（ILP）的鉴定。对新组装的多刺龙虾（Sagmariasus verreauxi）转录组进行生物信息学分析，鉴定出了Sv-ILP1以及八种结合蛋白。由于与脊椎动物胰岛素样生长因子结合蛋白具有同源性，结合蛋白被称为Sv-IGFBP，而与其他无脊椎动物物种中鉴定出的类似的单胰岛素结合域蛋白（SIBD）则被称为Sv-SIBD1-7。研究发现，Sv-ILP1在雌雄两性的眼柄、性腺和触角腺中均有表达，在雄性肌肉、雄激素腺和肝胰腺中的表达程度较低。通过PCR和数字基因表达发现，每种结合蛋白的表达谱在不同组织中存在差异，其中Sv-SIBD5、6和7在性腺中的表达较高。进一步利用原位杂交进行空间研究发现，Sv-ILP1在胸神经节的神经分泌细胞中表达，这与果蝇ILP7（DILP7）的组织表达情况一致。结合Sv-ILP1和DILP7的系统发育聚类情况来看，这种相关的组织表达表明Sv-ILP1是DILP7的直系同源物。Sv-ILP1的广泛表达强烈表明，ILP在十足目中的作用不仅仅是雄性化。这些新型肽的功能可能在增强具有商业重要性的十足目物种的水产养殖实践中具有应用价值。
