title: Molecular characterization and dietary regulation of aminopeptidase N (APN) in the grass carp (Ctenopharyngodon idella).
abstract: Aminopeptidase N (APN) is a member of the peptidase M1 family and plays an important role in protein digestion. In the present study, an APN gene was cloned from the intestine of Ctenopharyngodon idellus. The full-length cDNA sequence of APN encodes an 892-amino-acid peptide that includes one helix trans-membrane region. Phylogenetic analysis showed that the APN sequence clustered with Danio rerio as its closest neighbor, sharing a sequence similarity of 81.5%. APN mRNA was differentially expressed in different tissues, with a gradient expression from high to low in the tissues of the fore-intestine, hind-intestine, liver, mid-intestine, kidney, muscle, spleen and heart. APN expression in grass carp had a circadian pattern, showing time-dependent higher expression between 06:00 and 18:00 and lower expression between 18:00 and 06:00. In addition, the protein levels and resource in the diet-regulated APN expression suggested that low crude protein (CP) level and fish meal stimulated APN gene expression. Furthermore, the mRNA expression of APN in the intestine was significantly suppressed by high concentrations of glutamine and glutamine dipeptides, respectively. This study may provide valuable knowledge on the regulation of APN expression in teleost, which has potential applications for improving fish dietary formulations.
authors.affiliation: College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China; Department of Biological and Environmental Engineering, Changsha University, Changsha 410003, China.
authors.forename: Jianzhou
authors.initials: J
authors.lastname: Tang
authors.affiliation: Department of Biological and Environmental Engineering, Changsha University, Changsha 410003, China.
authors.forename: Fufa
authors.initials: F
authors.lastname: Qu
authors.affiliation: College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China.
authors.forename: Xiangbei
authors.initials: X
authors.lastname: Tang
authors.affiliation: Department of Biological and Environmental Engineering, Changsha University, Changsha 410003, China.
authors.forename: Qiong
authors.initials: Q
authors.lastname: Zhao
authors.affiliation: Department of Biological and Environmental Engineering, Changsha University, Changsha 410003, China.
authors.forename: Yonghong
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Biological and Environmental Engineering, Changsha University, Changsha 410003, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: Department of Biological and Environmental Engineering, Changsha University, Changsha 410003, China.
authors.forename: Junchang
authors.initials: J
authors.lastname: Feng
authors.affiliation: Department of Biological and Environmental Engineering, Changsha University, Changsha 410003, China.
authors.forename: Shuangqing
authors.initials: S
authors.lastname: Lu
authors.affiliation: College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China. Electronic address: K8469751@kadai.jp.
authors.forename: Dexing
authors.initials: D
authors.lastname: Hou
authors.affiliation: Department of Biological and Environmental Engineering, Changsha University, Changsha 410003, China; Feed Research Institute of Chinese Academy of Agricultural Sciences, Beijing 100081, China. Electronic address: 25300085@qq.com.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Liu
mesh_terms: D000818:Animals; D018826:CD13 Antigens / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D002347:Carps / Q000235:genetics* / Q000378:metabolism; D004032:Diet; D005786:Gene Expression Regulation; D012333:RNA, Messenger / Q000096:biosynthesis* / Q000235:genetics; D015027:Zebrafish / Q000235:genetics
chemical_list: D012333:RNA, Messenger; D018826:CD13 Antigens
keywords: Aminopeptidase N; Ctenopharyngodon idellus; Molecular characteristics; mRNA expression profile