Cloning and Expression Analysis of the MASP1 Gene from the Half-Smooth Tongue Sole (Cynoglossus semilaevis)

Abstract:

Mannan-binding lectin-associated serine protease 1 (MBL associated serine protease 1, MASP1) is an important activator in the complement lectin pathway. In this study, the cDNA of the MASP1 gene from Cynoglossus semilaevis (CsMASP1) was cloned using a RACE method based on the partial sequence of CsMASP1, and gene expression was performed by qRT-PCR. The results showed that the full length of cDNA was 2507 bp in size, including a 5′-untranslated region (UTR) of 82 bp, 3′-UTR of 142 bp, and a complete open reading frame (ORF) of 2283 bp, encoding 760 amino acids. The theoretical isoelectric point (pI) of the predicted protein was 5.33 and the molecular weight was 84.95 kDa. Homologous alignment showed that the amino acids sequence of CsMASP1 had a high identity with those of other species, approximately 42%~76%. The CsMASP1 gene was expressed in all tested tissues (liver, intestine, spleen, head-kidney, gill, blood, brain, skin, heart, trunk-kidney, and gonad) in the healthy C. semilaevis and the highest expression was in the liver (185.4). To study the expression patterns of the CsMASP1 gene in an immune response, the specific expression of CsMASP1 was performed after Vibrio anguillarum infection. The results showed that the expression of the CsMASP1 gene was up-regulated in the liver, gill, blood, intestine, head-kidney, and spleen after V. anguillarum infection. The most significantly up-regulated expression and the peak level at 6 h reached 15.4 times baseline in the spleen. The results indicate that the CsMASP1 genes are involved in the immune response.