摘要
In this study, we report on the isolation and characterization of an alpha2-macroglobulin (alpha 2M) from the plasma of the pink shrimp Farfantepenaeus paulensis, its sub-cellular localization and transcriptional changes after infection by fungi. The molecular mass of the alpha 2M was estimated at 389 kDa by gel filtration and 197 kDa by SDS-PAGE, under reducing conditions, suggesting that alpha 2Mfrom E paulensis consists of two identical sub-units, covalently linked by disulphide bonds. The N-terminal amino acid sequence of the alpha 2M from E paulensis was very similar to those of other penaeid shrimps, crayfish and lobster (70-90% identity) and to a less extent with that of freshwater prawn (40% identity). A monoclonal antibody raised against the Marsupenaeus japonicus alpha 2M made it possible to demonstrate that alpha 2M of E paulensis is stored in the vesicles of the shrimp granular hemocytes (through immunogold assay). Quantitative real-time PCR (qPCR) analysis showed that alpha 2M mRNA transcripts significantly increased 24 h after an experimental infection with the shrimp pathogen Fusarium solani and it returned to the basal levels at 48 h post-injection. This is the first report on a alpha 2M characterization in an Atlantic penaeid species and its expression profile upon a fungal infection.
- 出版日期2011-12