Functional characterization of STATa/b genes encoding transcription factors from Branchiostoma belcheri
Functional characterization of STATa/b genes encoding transcription factors from Branchiostoma belcheri
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文昌鱼转录因子 STATa/b 基因的功能表征
DOI：
10.1016/j.dci.2020.103838
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发表时间：
2021-01-01
影响因子：
2.9
通讯作者：
Ma, Fei
中科院分区：
文献类型：
--
作者：
Cao, Yunpeng;Fang, Tao;Ma, Fei
信号转导和转录激活因子（STAT）是Janus激酶（JAK）-STAT信号通路中的重要转录因子，在脊椎动物的发育和免疫中起着重要作用。然而，STAT基因在文昌鱼（Branchiostoma belcheri）中尚未报道。本研究首先从文昌鱼中分离鉴定了两个STAT基因（AmphiSTATa和AmphiSTATb）。其次，系统发育分析表明，AmphiSTATa与脊椎动物STAT 1、STAT 2、STAT 3和STAT 4聚在一起，而AmphiSTATb与STAT 5和STAT 6聚在一起。RT-qPCR分析发现AmphiSTATa和AmphiSTATb在文昌鱼的5种代表性组织（鳃、肝盲肠、肠、肌肉和脊索）中广泛表达。重要的是，AmphiSTATa和AmphiSTATb都可以参与对LPS刺激的先天免疫应答。第四，通过Co-IP和Native-PAGE分析，我们证明AmphiSTATa和AmphiSTATb可以形成同源二聚体或异源二聚体，并且通过亚细胞定位，我们证明AmphiSTATa和AmphiSTATb蛋白也可以分布在细胞质和细胞核中。综上所述，我们的研究结果不仅揭示了AmphiSTATa和AmphiSTATb在文昌鱼对LPS刺激的天然免疫应答中的作用，而且为进一步阐明STAT在动物中的进化和功能提供了新的见解。
The signal transducer and activator of transcription (STAT), as an important transcription factor of the Janus kinase (JAK)-STAT signaling pathway, is pivotal for development and immunity and well documented in vertebrates. However, the STAT gene has not been reported in chordate amphioxus (Branchiostoma belcheri). In this study, we firstly identify and characterize two STAT genes from Branchiostoma belcheri (designed as AmphiSTATa and AmphiSTATb). Secondly, our results reveal that AmphiSTATa is clustered with vertebrate STAT1, STAT2, STAT3 and STAT4, whereas AmphiSTATb is grouped with STAT5 and STAT6 based on phylogenetic analysis. Thirdly, AmphiSTATa and AmphiSTATb are found to widely express in five representative tissues of amphioxus (gill, hepatic cecum, intestine, muscle and notochord) by RT-qPCR analysis. Importantly, both AmphiSTATa and AmphiSTATb can be involved in innate immune responses to LPS stimulation. Fourthly, we demonstrate that AmphiSTATa and AmphiSTATb can form homodimers or hetemdimers by Co-IP and Native-PAGE assay, and that AmphiSTATa and AmphiSTATb proteins can also distribute in cytoplasm and nucleus by the subcellular localization. Taken together, our findings not only reveal the roles of AmphiSTATa and AmphiSTATb in amphioxus innate immune responses to LPS stimulation, but provide a new insight into further elucidating the evolution and function of STATs in animals.