Abstract：
Gasdermin (GSDM) proteins are executioners of pyroptosis in many species. Gasdermin proteins can be cleaved at their linker region between the amino domain (NT) and carboxyl domain (CT) by enzymes. The released GSDM-NTs bind cell membrane and form pores, thereby leading to the release of cellular components and lytic cell death. GSDM-mediated pyroptosis is considered to play important role in immune responses. However, little is known about the GSDM proteins and GSDM-mediated pyroptosis in birds. In the current study, genes encoding chicken gasdermin A (chGSDMA) and chGSDME were cloned. The cleavage of chGSDMA and chGSDME by chicken caspase-1 (chCASP1), chCASP3 and chCASP7 and the cleavage sites were determined. The chGSDMA-NT obtained form chCASP1-mediated cleavage and chGSDME-NT obtained from chCASP3/chCASP7-mediated cleavage could bind and damage cell membrane and lead to cell death of HEK293 cells. chGSDMA-NT also strongly localized to and formed puncta in nucleus. Besides, both chGSDMA-NT and chGSDME-NT showed growth inhibition and bactericidal activity to bacteria. In chickens challenged with Pasteurella multocida and Salmonella typhimurium, the expression of chGSDMA and chGSDME was upregulated and the activation of chCASP3 and the cleavage of chGSDME were observed. The work provides essential information for expanding our knowledge on pyroptosis in birds.
摘要：
Gasdermin（GSDM）蛋白是许多物种中焦亡的执行者。Gasdermin蛋白可以通过酶在其氨基结构域(NT)和羧基结构域(CT)之间的接头区处切割。释放的GSDM-NTs结合细胞膜并形成孔，从而导致细胞成分的释放和裂解性细胞死亡。GSDM介导的焦亡被认为在免疫应答中起重要作用。然而,对鸟类GSDM蛋白和GSDM介导的焦亡知之甚少。在目前的研究中,克隆了编码鸡gasderminA（chGSDMA）和chGSDME的基因。鸡caspase-1（chCASP1）对chGSDMA和chGSDME的裂解，确定chCASP3和chCASP7以及切割位点。从chCASP1介导的裂解获得的chGSDMA-NT和从chCASP3/chCASP7介导的裂解获得的chGSDME-NT可以结合并损伤细胞膜并导致HEK293细胞的细胞死亡。chGSDMA-NT也强烈定位并在细胞核中形成斑点。此外,chGSDMA-NT和chGSDME-NT均对细菌具有生长抑制和杀菌活性。在受到多杀性巴氏杆菌和鼠伤寒沙门氏菌攻击的鸡中，chGSDMA和chGSDME的表达上调，观察到chCASS3的激活和chGSDME的裂解。这项工作为扩大我们对鸟类焦度的了解提供了必要的信息。
