cDNA Cloning and Expression Analysis of F-ATPaseβ Subunit Gene in Portunus trituberculatus and Its Variation in Family Inbreeding

Abstract:

A full-length cDNA sequence of F-ATPase β subunit gene from Portunus trituberculatus (ptF-ATPaseβ) was cloned by rapid amplification of cDNA ends (RACE). The sequence of ptF-ATPaseβ was 1965 bp, containing a 571 bp 5' UTR, 341 bp 3' UTR, and a 1053 bp open reading frame (ORF) that encodes 350 amino acids polypeptides. The isoelectric point (pI) was 4.86 and the molecular mass was 37.9 kDa. The amino acid sequence analysis demonstrated that ptF-ATPaseβ has an F1-ATPaseβ domain, an AAA domain, and an ATP-synt-ab-C domain. Homology and phylogenetic analysis revealed that the amino acid sequence of ptF-ATPaseβ shared a high similarity (89%) with Penaeus monodon and Litopenaeus vannamei. ptF-ATPaseβ mRNA level was detected in all tested tissues including the hepatopancreas, muscle, heart, gill, stomach, intestine, testis, and ovary. The ptF-ATPaseβ had the highest level in the hepatopancreas and heart, and the lowest expression in the intestine. With the increase of inbreeding coefficient, ptF-ATPaseβ expression decreased significantly in the hepatopancreas and heart (P<0.05). The ATP synthase activity in the heart began to fall from F6 generation and was significantly lower than F0 generation (P<0.05), but there was no significant change in the hepatopancreas. The results illustrate that inbreeding gradually reduces the expression of ptF-ATPaseβ and the ATP synthase activity in P. trituberculatus.