Janus kinase 1 (JAK1) is a member of JAK family of non-receptor protein tyrosine kinases that plays critical roles in transducing cytokine signals via JAK-signal transducer and activator of transcription (STAT) signaling pathway. The importance of JAK1 in innate immunity has been well-studied in mammals and fish, yet in avian remains largely unknown. Here, we cloned the full-length of the duck JAK1 (duJAK1) gene for the first time. DuJAK1 encoded a protein of 1152 amino acids and possessed high amino acid identity with goose and budgerigar JAK1s. The duJAK1 was expressed in all detected tissues, especially high in the thymus and bursa of Fabricius. Overexpression of duJAK1 significantly activated ISRE promoter activity and induced duck viperin, 2', 5'-OAS, MX, PKR and ZAP expression. Knockdown of duJAK1 by small interfering RNA significantly inhibited duck Tembusu virus (DTMUV)-, duck Enteritis virus (DEV)-, poly (I:C)-, poly (dA:dT)- or Sendai virus (SeV)-induced ISRE promoter activation. Furthermore, duJAK1 exhibited antiviral activity against DTMUV infection. These results will help us understand the function of JAK family proteins in duck antiviral immunity.

中文翻译：

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鸭Janus激酶1的分子克隆与功能表征。

Janus激酶1（JAK1）是JAK非受体蛋白酪氨酸激酶家族的成员，在通过JAK信号转导子和转录激活子（STAT）信号转导通路传导细胞因子信号中起关键作用。在哺乳动物和鱼类中，JAK1在先天免疫中的重要性已得到充分研究，但在禽类中仍然未知。在这里，我们第一次克隆了鸭JAK1（duJAK1）基因的全长。DuJAK1编码一种1152个氨基酸的蛋白质，并与鹅和虎皮鹦鹉JAK1具有高度的氨基酸同一性。duJAK1在所有检测到的组织中都有表达，尤其在Fabricius的胸腺和法氏囊中高表达。duJAK1的过表达显着激活了ISRE启动子活性，并诱导了鸭viperin，2'，5'-OAS，MX，PKR和ZAP表达。用小干扰RNA敲低duJAK1可以显着抑制鸭天疱病病毒（DTMUV），鸭肠炎病毒（DEV），聚（I：C），聚（dA：dT）-或仙台病毒（SeV）诱导的ISRE启动子激活。此外，duJAK1表现出抗DTMUV感染的抗病毒活性。这些结果将帮助我们了解JAK家族蛋白在鸭抗病毒免疫中的功能。