Serum amyloid A in marine bivalves: An acute phase and innate immunity protein. (June 2016)

• Record Type: Journal Article
• Authors: Rosani, U.; Domeneghetti, S.; Gerdol, M.; Franzoi, M.; Pallavicini, A.; Venier, P.
• Is Part Of: Developmental and comparative immunology. Volume 59(2016)
• Page Start: 136
• Page End: 144
• Publication Date: 2016-06
• Subjects: SAA -- Bivalves -- Immunity -- Protostomes; Immunology -- Periodicals; Developmental immunology -- Periodicals; 616.079
• DOI: 10.1016/j.dci.2016.01.019
• Languages: English
• ISSNs: 0145-305X

Abstract

Abstract: Serum amyloid A (SAA) is among the most potent acute phase proteins (APP) in vertebrates. After injury, its early expression can dramatically increase to promote the recruitment of immuno-competent cells, expression of pro-inflammatory proteins and the activation of the innate immune defences. Although APP have been studied in many vertebrates, only recently their search was extended to invertebrates and the finding of SAA-like molecules has opened new questions on the immune-regulatory functions of these soluble proteins in the animal kingdom. Taking advantage of the considerable amount of genomic and transcriptomic data currently available, we retrieved 51 SAA-like proteins in several protostome taxa comprising 21 marine bivalve species and basal metazoans. In addition to vertebrate-like SAAs, we identified a second protein type with peculiar features. In the bivalves Crassostrea gigas and Mytilus galloprovincialis, both digital expression analysis and qPCR data indicated an induction of the classical SAA after bacterial challenge. Highlights: We back-traced Serum Amyloid A (SAA) through metazoan evolution, to cnidarians. SAA-like sequences are present in several marine bivalves. Bivalve SAAs are structurally similar to the vertebrate ones. Mussel SAA transcripts are highly induced after bacterial challenge.