CAJ | 학술논문

用RT-PCR方法,从黄颡鱼(Pelteobagrus fulvidraco)肝脏中克隆获得了Hepcidin(heppatic bactericidal protein)cDNA序列,并对其进行序列测定,分析了Hepcidin基因在不同组织中的表达差异和不同细菌感染后对其表达的影响.结果表明,黄颡鱼Hepcidin cDNA片段(GenBank登录号:EU257703)长为282 bp,编码93个氨基酸,由信号肽(23个氨基酸)、前肽(45个氨基酸)和成熟肽(25个氨基酸)组成,成熟肽含有8个保守的半胱氨酸(Cys)残基,可形成4个链内二硫键.与已报道的其它鲶形目鱼类Hepcidin核苷酸序列的同源性为80%～82%,推导的氨基酸序列的同源性为69%～71%.RT-PCR半定量分析显示,黄颡鱼Hepcidin基因在不同组织中普遍表达,其中肝脏表达水平最高,头肾、肠道、肌肉、脑、胃、鳃、心脏、卵巢和肾脏表达次之,皮肤和脾脏表达较低.感染嗜水单胞菌(Aeromonas hydrophila)和腊样芽胞杆菌(Bacillus cereus)的黄颡鱼,肝脏Hepcidin mRNA水平显著升高(P＜0.05).
용RT-PCR방법,종황상어(Pelteobagrus fulvidraco)간장중극륭획득료Hepcidin(heppatic bactericidal protein)cDNA서렬,병대기진행서렬측정,분석료Hepcidin기인재불동조직중적표체차이화불동세균감염후대기표체적영향.결과표명,황상어Hepcidin cDNA편단(GenBank등록호:EU257703)장위282 bp,편마93개안기산,유신호태(23개안기산)、전태(45개안기산)화성숙태(25개안기산)조성,성숙태함유8개보수적반광안산(Cys)잔기,가형성4개련내이류건.여이보도적기타염형목어류Hepcidin핵감산서렬적동원성위80%～82%,추도적안기산서렬적동원성위69%～71%.RT-PCR반정량분석현시,황상어Hepcidin기인재불동조직중보편표체,기중간장표체수평최고,두신、장도、기육、뇌、위、새、심장、란소화신장표체차지,피부화비장표체교저.감염기수단포균(Aeromonas hydrophila)화석양아포간균(Bacillus cereus)적황상어,간장Hepcidin mRNA수평현저승고(P＜0.05).
Antimicrobial peptides (AMPs) are regarded as important components of the host innate immune system and play crucial roles in host defense against microbial invasion. Hepcidin(heppatic bactericidal protein) is an antimicrobial peptide and iron regulatory molecule primarily in liver. One Hepcidin gene was amplified from the liver of yellow catfish (Pelteobagrus fulvidraco) by RT-PCR. The length of Hepcidin cDNA fragment (GenBank accession No. EU257703 ) was 282 bp with an ORF ranging from 1st to279th bp, which encoded a peptide of 93 amino acids. According to the Blast result in GenBank database, the cDNA nucleotides and the deduced amino acid sequence of ORF share 80%～82% and 69%～71% identity with those of other species in Siluriformes, respectively. The prepropeptide contained a signal peptide (23 amino acids), a prodomain (45 amino acids) and a mature peptide(25amino acids). The predicted 25-amino acid Hepcidin mature peptide included 8 conserved cysteine residues which were proposed to form four disulphide bonds. RT-PCR demonstrated that the Hepcidin gene was expressed in a wide range of tissues of yellow catfish.And the Hepcidin transcripts were highly abundant in liver, abundant in head kidney, intestine, muscle, brain, stomach, gill, heart, ovary and tnmk kidney, less abundant in skin and spleen, respectively. Challenge of yellow catfish with Aeromonas hydrophila and Bacillus cereus significantly elevated Hepcidin mRNA levels in liver. The new member of Hepcidin discovered in this study can contribute to the research of immune function and mechanism in yellow catfish.