title: The chemokinome superfamily in channel catfish: I. CXC subfamily and their involvement in disease defense and hypoxia responses.
abstract: Chemokines are a superfamily of structurally related chemotactic cytokines exerting significant roles in regulating cell migration and activation. They are defined by the presence of four conserved cysteine residues and are divided into four subfamilies depending on the arrangement of the first two conserved cysteines residues: CXC, CC, C and CX3C. In this study, a complete set of 17 CXC chemokine ligand (CXCL) genes was systematically identified and characterized from channel catfish genome through data mining of existing genomic resources. Phylogenetic analysis allowed annotation of the 17 CXC chemokines. Extensive comparative genomic analyses supported their annotations and orthologies, revealing the existence of fish-specific CXC chemokines and the expansion of CXC chemokines in the teleost genomes. The analysis of gene expression after bacterial infection indicated the CXC chemokines were expressed in a gene-specific manner. CXCL11.3 and CXCL20.3 were expressed significantly higher in resistant fish than in susceptible fish after ESC infection, while CXCL20.2 were expressed significantly higher in resistant fish than in susceptible fish after columnaris infection. The expression of those CXC chemokines, therefore can be a useful indicator of disease resistance. A similar pattern of expression was observed between resistant and susceptible fish with biotic and abiotic stresses, ESC, columnaris and hypoxia, suggesting that high levels of expression of the majority of CXC chemokines, with exception of CXC11 and CXC20, are detrimental to the host.
authors.affiliation: State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai 200062, China; The Fish Molecular Genetics and Biotechnology Laboratory, Aquatic Genomics Unit, School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, AL 36849, USA.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Fu
authors.affiliation: The Fish Molecular Genetics and Biotechnology Laboratory, Aquatic Genomics Unit, School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, AL 36849, USA.
authors.forename: Qifan
authors.initials: Q
authors.lastname: Zeng
authors.affiliation: The Fish Molecular Genetics and Biotechnology Laboratory, Aquatic Genomics Unit, School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, AL 36849, USA.
authors.forename: Yun
authors.initials: Y
authors.lastname: Li
authors.affiliation: The Fish Molecular Genetics and Biotechnology Laboratory, Aquatic Genomics Unit, School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, AL 36849, USA.
authors.forename: Yujia
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Marine Science and Engineering College, Qingdao Agricultural University, Qingdao 266109, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Li
authors.affiliation: The Fish Molecular Genetics and Biotechnology Laboratory, Aquatic Genomics Unit, School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, AL 36849, USA.
authors.forename: Shikai
authors.initials: S
authors.lastname: Liu
authors.affiliation: The Fish Molecular Genetics and Biotechnology Laboratory, Aquatic Genomics Unit, School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, AL 36849, USA.
authors.forename: Tao
authors.initials: T
authors.lastname: Zhou
authors.affiliation: The Fish Molecular Genetics and Biotechnology Laboratory, Aquatic Genomics Unit, School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, AL 36849, USA.
authors.forename: Ning
authors.initials: N
authors.lastname: Li
authors.affiliation: The Fish Molecular Genetics and Biotechnology Laboratory, Aquatic Genomics Unit, School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, AL 36849, USA.
authors.forename: Jun
authors.initials: J
authors.lastname: Yao
authors.affiliation: The Fish Molecular Genetics and Biotechnology Laboratory, Aquatic Genomics Unit, School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, AL 36849, USA.
authors.forename: Chen
authors.initials: C
authors.lastname: Jiang
authors.affiliation: State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai 200062, China.
authors.forename: Daoji
authors.initials: D
authors.lastname: Li
authors.affiliation: The Fish Molecular Genetics and Biotechnology Laboratory, Aquatic Genomics Unit, School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, AL 36849, USA. Electronic address: liuzhan@auburn.edu.
authors.forename: Zhanjiang
authors.initials: Z
authors.lastname: Liu
mesh_terms: D000693:Anaerobiosis / Q000235:genetics; D000818:Animals; D019743:Chemokines, CXC / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D060467:Disease Resistance / Q000235:genetics; D020610:Edwardsiella ictaluri / Q000502:physiology; D004756:Enterobacteriaceae Infections / Q000235:genetics / Q000276:immunology / Q000382:microbiology / Q000662:veterinary*; D005393:Fish Diseases / Q000235:genetics* / Q000276:immunology / Q000382:microbiology; D029941:Fish Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D045826:Flavobacteriaceae Infections / Q000235:genetics / Q000276:immunology / Q000382:microbiology / Q000662:veterinary*; D005417:Flavobacterium / Q000502:physiology; D015870:Gene Expression; D007059:Ictaluridae; D010802:Phylogeny; D017422:Sequence Analysis, DNA / Q000662:veterinary; D026801:Synteny
chemical_list: D019743:Chemokines, CXC; D029941:Fish Proteins
keywords: Chemokine; Disease resistance; Fish; Genome; Innate immunity