广西黄鸡β-防御素Gal-4基因的克隆和体内诱导表达

Cloning and in vivo expression ofβ-defensin Gal-4 gene of Guangxi Yellow chicken

采用RT-PCR方法从广西黄鸡骨髓中扩增了β-防御素Gal-4基因的cDNA片段。序列分析结果表明,获得的广西黄鸡Gal-4基因大小为321 bp,推导的Gal-4由63个氨基酸组成,其中N端20个氨基酸为信号肽,C端38个氨基酸组成Gal-4的成熟肽。另外,分析了Gal-4基因在正常广西黄鸡(对照组)和H9N2禽流感病毒感染的广西黄鸡(感染组)的肺、肝、腔上囊、十二指肠、肾、气管组织中的表达情况。分析结果表明,在检测的6个组织中,肺、十二指肠、肾组织Gal-4基因的表达在感染组和对照组之间没有明显的差别,而在肝、气管和腔上囊组织中的表达有明显差异,感染组比对照组的Gal-4阳性样品数多。在肝组织中,对照组的30个样品检测到26个阳性样品,而感染组的30个样品全都是阳性；在气管组织中,对照组30个样品检测到19个阳性样品,而感染组的30个样品检测到24个阳性样品；在腔上囊组织中,Gal-4基因的诱导表达情况非常明显,对照组30个样品中仅有9个阳性,而感染组的30个样品中有21个阳性。

β-defensin gallinacin-4（Gal-4） cDNA fragment was amplified from bone marrow of Guangxi Yellow chicken by RT-PCR. Sequence analysis of Gal-4 cDNA showed that the cDNA of Gal-4 gene consists of 321 bp, encoding Gal-4 polypeptide of 63 amino acids, which comprised of signal peptide with 20 amino acids at N＇terminus, and mature peptide with 38 amino acids. Inducible expression pattern in vivo of Gal-4 gene was analyzed using RT-PCR in lung, liver, Fabricius＇ bursa, duodenum, kidney, and trachea of both the control Guangxi Yellow chickens and the chickens infected with H9N2 subtype avian influenza virus（AIV）. The data showed that the expression pattern of Gal-4 gene had no significant change in lung, duodenum and kidney tissues after infection with H9N2 AIV while the expression of Gal-4 gene were induced in liver, Fabricius＇ bursa and trachea tissues, between the infected and the control. In 30 liver tissues, there was 26 positive samples in the control, and 30 positive in the infected chickens. In 30 trachea tissues, there was 19 positive samples in the control, and 24 positive in the infected flock. In 30 Fabricius＇ bursa tissues, there was only 9 positive samples in the control, and 21 positive in the infected chickens.