AHCYL1 Is Mediated by Estrogen-Induced ERK1/2 MAPK Cell Signaling and MicroRNA Regulation to Effect Functional Aspects of the Avian Oviduct

S-adenosylhomocysteine hydrolase-like protein 1 (AHCYL1), also known as IP3 receptor-binding protein released with IP3 (IRBIT), regulates IP3-induced Ca2+ release into the cytoplasm of cells. AHCYL1 is a critical regulator of early developmental stages in zebrafish, but little is known about the function of AHCYL1 or hormonal regulation of expression of the AHCYL1 gene in avian species. Therefore, we investigated differential expression profiles of the AHCYL1 gene in various adult organs and in oviducts from estrogen-treated chickens. Chicken AHCYL1 encodes for a protein of 540 amino acids that is highly conserved and has considerable homology to mammalian AHCYL1 proteins (>94% identity). AHCYL1 mRNA was expressed abundantly in various organs of chickens. Further, the synthetic estrogen agonist induced AHCYL1 mRNA and protein predominantly in luminal and glandular epithelial cells of the chick oviduct. In addition, estrogen activated AHCYL1 through the ERK1/2 signal transduction cascade and that activated expression of AHCYL1 regulated genes affecting oviduct development in chicks as well as calcium release in epithelial cells of the oviduct. Also, microRNAs, miR-124a, miR-1669, miR-1710 and miR-1782 influenced AHCYL1 expression in vitro via its 3′-UTR which suggests that post-transcriptional events are involved in the regulation of AHCYL1 expression in the chick oviduct. In conclusion, these results indicate that AHCYL1 is a novel estrogen-stimulated gene expressed in epithelial cells of the chicken oviduct that likely affects growth, development and calcium metabolism of the mature oviduct of hens via an estrogen-mediated ERK1/2 MAPK cell signaling pathway.S-腺苷同型半胱氨酸水解酶样蛋白1（AHCYL1），亦称与肌醇三磷酸（inositol trisphosphate，IP3）一同释放的IP3受体结合蛋白（IRBIT），可调控IP3诱导的钙离子释放入细胞胞质。AHCYL1是斑马鱼早期发育阶段的关键调控因子，但目前对于禽类中AHCYL1的功能及其基因表达的激素调控机制仍知之甚少。为此，本研究探究了AHCYL1基因在成年鸡各组织以及雌激素处理鸡输卵管中的差异表达谱。鸡AHCYL1编码一条含540个氨基酸的蛋白质，该蛋白具有高度保守性，与哺乳动物AHCYL1蛋白的同源性极高（序列一致性>94%）。AHCYL1信使RNA（messenger RNA，mRNA）在鸡的多种组织中均有丰富表达。进一步研究发现，合成雌激素激动剂可主要在雏鸡输卵管的腔上皮细胞与腺上皮细胞中诱导AHCYL1的mRNA与蛋白表达。此外，雌激素可通过ERK1/2信号转导级联激活AHCYL1，而AHCYL1的激活可调控影响雏鸡输卵管发育以及输卵管上皮细胞钙离子释放的相关基因。同时，微小RNA（microRNA，miRNA）miR-124a、miR-1669、miR-1710及miR-1782可通过AHCYL1的3′非翻译区（3′-UTR）在体外影响其表达，这提示转录后调控事件参与了雏鸡输卵管中AHCYL1的表达调控。综上，本研究结果表明，AHCYL1是一种在鸡输卵管上皮细胞中表达的新型雌激素应答基因，其可能通过雌激素介导的ERK1/2丝裂原活化蛋白激酶（mitogen-activated protein kinase，MAPK）细胞信号通路，影响母鸡成熟输卵管的生长、发育与钙代谢。