College of Agriculture, Ibaraki University, Ibaraki, Japan.
Anim Sci J. 2019 Sep;90(9):1293-1302. doi: 10.1111/asj.13261. Epub 2019 Jul 16.
The molecular mechanism underlying in the onset and maintenance of incubation behavior are not fully understood, and it is still unknown the reason why White Leghorn, a layer strain, hens never display incubation behavior. Therefore, to explore specific hypothalamic genes regulating incubation behavior, cap analysis of gene expression (CAGE) were applied to comparison between incubating Silkie and laying White Leghorn hens. In addition, mRNA expression of some differentially expressed genes (DEGs) and melanocortinergic appetite genes including agouti-related peptide (AgRP) and pro-opiomelanocortin (POMC) was also analyzed on Silkie hens under natural anorexia and starvation. The CAGE identified 217 hypothalamic DEGs in incubating Silkie hens, and that of two, transthyretin (TTR) and prolactin-releasing peptide (PrRP), suggested as appetite gene, were markedly up- and down-regulated in incubating hens, respectively. In addition, AgRP and POMC expression also increased in incubating bird. mRNA expression of TTR, PrRP, and appetite genes were not differed significantly by starvation, although TTR mRNA expression was relatively high in fasting hens. Consequently, transcriptome by CAGE identified a number of hypothalamic genes differentially expressed by incubation behavior in Silkie hens. Of these, it is suggested that TTR and PrRP may, at least in part, be related to adaptation to natural anorexia in incubating Silkie chickens.
孵育行为的发生和维持的分子机制尚不完全清楚，也不知道为什么白来航鸡（一种蛋鸡品种）母鸡从不表现出孵育行为。因此，为了探索特定的调节孵育行为的下丘脑基因，我们应用了基因表达的帽分析（CAGE）技术，对孵育的丝羽乌骨鸡和产蛋的白来航母鸡进行了比较。此外，还分析了一些差异表达基因（DEGs）和黑皮质素能食欲基因（如 AgRP 和 POMC）在自然厌食和饥饿状态下的丝羽乌骨鸡中的 mRNA 表达。CAGE 鉴定出孵育的丝羽乌骨鸡下丘脑的 217 个 DEGs，其中 TTR 和 PrRP 作为食欲基因，分别明显上调和下调。此外，孵育的鸟类中 AgRP 和 POMC 的表达也增加了。尽管禁食母鸡的 TTR mRNA 表达相对较高，但饥饿对 TTR、PrRP 和食欲基因的 mRNA 表达没有显著影响。因此，CAGE 的转录组鉴定出了丝羽乌骨鸡孵育行为差异表达的许多下丘脑基因。其中，TTR 和 PrRP 可能至少部分与孵育丝羽乌骨鸡对自然厌食的适应有关。
