title: Four lysozymes (one c-type and three g-type) in catfish are drastically but differentially induced after bacterial infection.
abstract: Lysozyme is an important component of the innate immune system. In this study, four lysozyme genes including one c-type lysozyme and three g-type lysozymes were identified from channel catfish (Ictalurus punctatus). The lysozyme genes are highly conserved in their structural features as compared to those from other species. Phylogenetic analyses were conducted allowing annotation of these genes. Additional analyses using conserved syntenies allowed determination of orthologies for the c-type lysozyme. Phylogenetic analysis indicated that the g-type lysozyme may have gone through species-specific gene duplications leading to multiple copies in some teleost species. Channel catfish possessed three copies of the g-type lysozyme genes. Expression analysis revealed that the catfish lysozyme genes were expressed in a broad range of tissues. The highest levels of expression were found in head kidney, liver, spleen, and trunk kidney, compatible with the immune functions of these tissues/organs. The c-type and g-type lysozymes were drastically induced after bacterial infection, but exhibited large differences in the extent of induction and the tissue with the highest level of induction, with the g-type lysozyme being most highly induced in the head kidney whereas the other three lysozymes being most highly induced in the liver, suggesting their cooperative actions in the immune responses but difference in their detailed functions.
authors: Department of Fisheries and Allied Aquacultures and Program of Cell and Molecular Biosciences, Aquatic Genomics Unit, Auburn University, Auburn, AL 36849, USA.
authors: Ruijia
authors: R
authors: Wang
authors: Jianbin
authors: J
authors: Feng
authors: Chao
authors: C
authors: Li
authors: Shikai
authors: S
authors: Liu
authors: Yu
authors: Y
authors: Zhang
authors: Zhanjiang
authors: Z
authors: Liu
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D020610:Edwardsiella ictaluri / Q000502:physiology; D004756:Enterobacteriaceae Infections / Q000276:immunology / Q000662:veterinary*; D005393:Fish Diseases / Q000276:immunology*; D029941:Fish Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D007059:Ictaluridae / Q000235:genetics* / Q000276:immunology* / Q000378:metabolism; D009113:Muramidase / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D009928:Organ Specificity; D010802:Phylogeny; D016133:Polymerase Chain Reaction / Q000662:veterinary; D016415:Sequence Alignment / Q000662:veterinary
chemical_list: D029941:Fish Proteins; D009113:Muramidase