title: Mucosal expression signatures of two Cathepsin L in channel catfish (Ictalurus punctatus) following bacterial challenge.
abstract: The mucosal surfaces of fish are the first line of host defense against various pathogens. The mucosal immune responses are the most critical events to prevent pathogen attachment and invasion. Cathepsins are a group of peptidases that involved in different levels of immune responses, but the knowledge of the roles of Cathepsin in mucosal immune responses against bacterial infection are still lacking. Therefore, in the present study we characterized the Cathepsin L gene family in channel catfish, and profiled their expression levels after challenging with two different Gram-negative bacterial pathogens. Here, two Cathepsin L genes were identified from channel catfish and were designated CTSL1a and CTSL.1. Comparing to other fish species, the catfish CTSL genes are highly conserved in their structural features. Phylogenetic analysis was conducted to confirm the identification of CTSL genes. Expression analysis revealed that the CTSL genes were ubiquitously expressed in all tested tissues. Following infection, the CTSL genes were significantly induced at most timepoints in mucosal tissues. But the expression patterns varied depending on both pathogen and tissue types, suggesting that CTSL genes may exert disparate functions or exhibit distinct tissue-selective roles in mucosal immune responses. Our findings here, clearly revealed the key roles of CTSL in catfish mucosal immunity; however, further studies are needed to expand functional characterization and examine whether CTSL may also play additional physiological roles in catfish mucosal tissues.
authors.affiliation: Marine Science and Engineering College, Qingdao Agricultural University, Qingdao 266109, China.
authors.forename: Renjie
authors.initials: R
authors.lastname: Wang
authors.affiliation: Marine Science and Engineering College, Qingdao Agricultural University, Qingdao 266109, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Song
authors.affiliation: Key Laboratory of Freshwater Aquatic Biotechnology and Breeding, Ministry of Agriculture, Heilongjiang Fisheries Research Institute, Chinese Academy of Fishery Sciences, Harbin 150070, China.
authors.forename: Baofeng
authors.initials: B
authors.lastname: Su
authors.affiliation: School of Fisheries, Aquaculture, and Aquatic Sciences, Auburn University, Auburn, AL 36849, USA.
authors.forename: Honggang
authors.initials: H
authors.lastname: Zhao
authors.affiliation: School of Fisheries, Aquaculture, and Aquatic Sciences, Auburn University, Auburn, AL 36849, USA.
authors.forename: Dongdong
authors.initials: D
authors.lastname: Zhang
authors.affiliation: School of Fisheries, Aquaculture, and Aquatic Sciences, Auburn University, Auburn, AL 36849, USA.
authors.forename: Eric
authors.initials: E
authors.lastname: Peatman
authors.affiliation: Marine Science and Engineering College, Qingdao Agricultural University, Qingdao 266109, China. Electronic address: leoochao@163.com.
authors.forename: Chao
authors.initials: C
authors.lastname: Li
mesh_terms: D016980:Aeromonas hydrophila / Q000502:physiology; D000595:Amino Acid Sequence; D000818:Animals; D056668:Cathepsin L / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; 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; D005786:Gene Expression Regulation; D016905:Gram-Negative Bacterial Infections / Q000235:genetics / Q000276:immunology / Q000382:microbiology / Q000662:veterinary; D007059:Ictaluridae; D018928:Immunity, Mucosal; D009092:Mucous Membrane / Q000276:immunology / Q000378:metabolism; D010802:Phylogeny; D016415:Sequence Alignment / Q000662:veterinary
chemical_list: D029941:Fish Proteins; D056668:Cathepsin L
keywords: Catfish; Cathepsin; Infection; Mucosal immunity