【作者】 徐文斐； 刘萍； 李建； 李吉涛； 陈萍；

【Author】 Wenfei Xu 1, 2 , Ping Liu 1* , Jian Li 2 , Jitao Li 2 , Ping Chen 2 (1.Ocean University of Dalian, Dalian, 116023; 2.Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Science, Qingdao, 266071)

【机构】 大连海洋大学； 中国水产科学研究院黄海水产研究所；

【摘要】 从脊尾白虾中成功克隆到抗脂多糖因子(ALF)的cDNA全长。该cDNA全长936bp,编码由134个氨基酸组成的蛋白质,该蛋白分子量为14844.06Da,等电点pI为6.09,有26个氨基酸的信号肽和两个保守的半胱氨酸残基形成的一个LPS结合位点。RT-PCR研究表明,ALF基因在脊尾白虾血细胞、眼柄和腮中有高水平的组成型表达,在鳗弧菌、粪肠球菌和WSSV病毒刺激后,ALF基因在各组织中均有明显增加,表明其作为一种抗菌肽类效应分子,在清除病原的防御反应中起着重要作用。在不同病原体刺激下,ALF免疫应答表现出相对于革兰氏阳性菌,对革兰氏阴性菌和病毒有较强免疫作用。更多还原

【Abstract】 A new ALF gene (designated as EcALF) was isolated from Exopalaemon carinicauda. Using RACE PCR method to amplify a full-length cDNA fragment of 936 bp coding for the mature 14844.06 kDa EcALF protein composed of 134 amino acids, contained a signal peptide and two conserved cysteine residues forming one disulfide loop. The tissue expression pattern of EcALF transcript and its temporal response to Vibrio alginolyticus, Enterococcus faecalis and WSSV challenge were examined. EcALF transcription could be detected in all tissues, with high mRNA levels found in haemocytes, eyestalk and gill, intermediate levels in the ovary and muscle, stomach and hepatopancreas and very low, barely detectable levels in the intestines. And the expression of EcALF transcripts in haemocytes were found to up-regulate considerably during the first 3 h after pathogen challenge and acupuncture control, especially acupuncture and E. faecalis challenge. This might be pointing out to the fact that this ALF gene is more related to antibacterial (Gram-negative) and antiviral activities than to antibacterial (Gram-positive) defense.更多还原