Identification and expression analysis of a fibrinogen alpha chain-like gene in Atlantic salmon (Salmo salar)

Fibrinogen is a protein involved in platelet aggregation that is essential for the coagulation of blood, and it plays a role in the fish immune system. In this study, a fibrinogen alpha chain-like gene of the Atlantic salmon (Salmo salar) (designated Ss-FGA) was cloned, and its expression pattern was analyzed after fish were infected by the bacterium Aeromonas salmonicida. The Ss-FGA gene contains a 135 base pair (bp) 5'-untranslated region (UTR), an open reading frame (ORF) of 1512 bp that encodes a 503 amino acid polypeptide, and a 624 bp 3'-UTR. The expression level of Ss-FGA was higher in the liver than in other tissues, indicating that the liver is the major organ for protein synthesis of Ss-FGA. Additionally, expression levels of Ss-FGA differed between treatment and control samples. The results of FISH (Fluorescence in situ hybridization) showed that the expression of Ss-FGA gene in the liver tissue of Atlantic salmon after infected by A. salmonicida. In conclusion, this study revealed that Ss-FGA might play important roles in the innate immune responses to bacterial invasion in Atlantic salmon.

Automated summary

This study cloned a fibrinogen alpha chain-like gene from Atlantic salmon, analyzed its expression pattern after infection by the bacterium Aeromonas salmonicida, and found that it may play important roles in the innate immune responses to bacterial invasion in Atlantic salmon. The study highlighted the significance of Ss-FGA in the immune system of Atlantic salmon.