title: Molecular characterization and expression of Lck in Nile tilapia (Oreochromis niloticus) in response to Streptococcus agalactiae stimulus.
abstract: Lymphocyte-specific protein tyrosine kinase (Lck) plays a critical role in effective signal transductions that are fundamental to T cell differentiation, proliferation, and effector functions. In this paper, the Lck gene of Nile tilapia, Oreochromis niloticus (designated as On-Lck), was cloned and its expression pattern under the stimulation of Streptococcus agalactiae was investigated. Sequence analysis showed important structural characteristics required for T cell receptor (TCR) signal transduction were detected in the deduced amino acid sequence of On-Lck, and the deduced genomic structure of On-Lck was similar to the known Lck. In healthy Nile tilapia, the On-Lck transcripts were mainly detected in the thymus, spleen, head kidney, and gill. When immunized with inactivated S. agalactiae, the On-Lck mRNA expression was significantly upregulated in the thymus, spleen, and head kidney. Moreover, there was a clear time-dependent expression pattern of On-Lck after immunization, and the expression reached the highest level at 48 h in the spleen and thymus and at 72 h in the head kidney, respectively. This is the first report on the expression of Lck induced by intracellular bacteria vaccination in teleosts. These findings indicated that On-Lck may play an important role in the immune response to intracellular bacteria in Nile tilapia.
authors.affiliation: College of Fishery, Guangdong Ocean University, Zhanjiang, 524025, China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Gan
authors.forename: Bei
authors.initials: B
authors.lastname: Wang
authors.forename: Yishan
authors.initials: Y
authors.lastname: Lu
authors.forename: Weiwei
authors.initials: W
authors.lastname: Zhu
authors.forename: Yu
authors.initials: Y
authors.lastname: Huang
authors.forename: JiChang
authors.initials: J
authors.lastname: Jian
authors.forename: Zaohe
authors.initials: Z
authors.lastname: Wu
mesh_terms: D000818:Animals; D023681:Cichlids / Q000235:genetics / Q000276:immunology / Q000382:microbiology; D005393:Fish Diseases / Q000201:enzymology* / Q000235:genetics / Q000276:immunology / Q000382:microbiology*; D029941:Fish Proteins / Q000235:genetics* / Q000378:metabolism; D007668:Kidney / Q000276:immunology; D019860:Lymphocyte Specific Protein Tyrosine Kinase p56(lck) / Q000235:genetics* / Q000276:immunology; D013154:Spleen / Q000276:immunology; D013290:Streptococcal Infections / Q000201:enzymology / Q000235:genetics / Q000382:microbiology / Q000662:veterinary*; D013292:Streptococcus agalactiae / Q000235:genetics / Q000502:physiology*; D013950:Thymus Gland / Q000276:immunology; D015854:Up-Regulation
chemical_list: D029941:Fish Proteins; D019860:Lymphocyte Specific Protein Tyrosine Kinase p56(lck)