Molecular cloning and expression of major histocompatibility complex class Ⅱβ gene in tissues of Siberian sturgeon Acipenser baerii
TIAN Zhao-hui，XU Shao-gang，HU Hong-xia，WANG Wei，DONG Ying，DONG Tian，SUN Ai
Beijing Key Laboratory of Fishery Biotechnology, Beijing Fisheries Research Institute and National Engineering Research Center for Freshwaters(Beijing), Beijing 100068, China
Abstract: In this study,major histocompatibility (MHC)Ⅱβ cDNA was cloned from Siberian sturgeon Acipenserbaerii by RACE.Sequence comparison indicated that the deduced amino acid sequence with 1443 bp including 801 bp open reading frame deducing 184 amino acids had 46%-83% identity with those of other species.The smart sequence analysis revealed that it had signal peptide, SMART MHC_Ⅱ_beta domain, SMART ⅠGc1 domain and transmembrane helix region.Real-time quantitative RT-PCR indicated that the MHCⅡβ was ubiquitously expressed in ten normal tissues including skin, meat, heart, gill, liver, spleen, intestine, kidney, brain and blood, higher in spleen，kindy and blood, and lower in liver, heart, intestine and brain，and nearly no in muscle and skin.There was significantly lower MHC Ⅱβ expression in spleen of the Siberian sturgeon challenged with bacterium Aeromonasveronii for 40 h than that in the control fish(P<0.05), recover to normal level in 96 h, indicating that MHCⅡβ is involved in the immunity of Sibreian sturgeon.
2019, Vol. 34 
