Molecular characterization and expression of CD48 in Nile tilapia (Oreochromis niloticus) in response to different stimulus

Zhiwen Wang, Caixia Xie, Yuan Li, Jia Cai, Jufen Tang, Jichang Jian, Kevin WH Kwok, Yishan Lu

Research output: Journal article publicationJournal articleAcademic researchpeer-review

1 Citation (Scopus)

Abstract

CD48 is a glycosylphosphatidylinositol-anchored protein involved in lymphocyte adhesion, activation, and costimulation. In this study, the CD48 gene of tilapia (Oreochromis niloticus, named On-CD48), was cloned from the head kidney of tilapia. The coding sequences is 654 bp and encoding 217 amino acids. The deduced amino acid sequence of On-CD48 with an estimated molecular weight of 24.4 kDa and a theoretical pI of 5.03. Amino acid alignment indicated that it had two immunoglobulin-like domain conserved region. In healthy tilapia, the On-CD48 could be detected in all the examined tissues and the highest expression level in the spleen. The expression of On-CD48 in the spleen and head kidney was decreased after immunized by formalin-inactivated Streptococcus agalactiae, and the peak was observed in the spleen at 24 h and appeared again at 96 h, and in the head kidney gradual decline before 48 h then gradually increased to the original level. qPCR analysis of inactivated S. agalactiae, LPS and Poly I:C stimulated at the whole lymphocyte level showed that the stimulation of the Poly I:C was more sensitive. Prokaryotic expression results showed that efficient expression of On-CD48 protein could be realized after induced with 0.5 mmol L−1 IPTG in E. coli BL21 (DE3) for 10 h at 18 °C. The result of subcellular localization showed that On-CD48 were evenly distributed in the whole cell of HEK-293T. Western Blot confirmed that the molecular weight of the recombinant On-CD48 was about 21 kDa, consistent with the predicted result. The results of this study will lay a strong foundation for the further study of On-CD48 molecular function in tilapia.

Original languageEnglish
Pages (from-to)515-522
Number of pages8
JournalFish and Shellfish Immunology
Volume97
DOIs
Publication statusPublished - Feb 2020

Keywords

  • CD48
  • mRNA expression
  • Oreochromis niloticus
  • Prokaryotic expression

ASJC Scopus subject areas

  • Environmental Chemistry
  • Aquatic Science

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