TY - JOUR
T1 - Biochemical and proteomic characterisation of haemolymph serum reveals the origin of the alkali-labile phosphate (ALP) in mussel (Mytilus galloprovincialis)
AU - Oliveri, Caterina
AU - Peric, Lorena
AU - Sforzini, Susanna
AU - Banni, Mohammed
AU - Viarengo, Aldo
AU - Cavaletto, Maria
AU - Marsano, Francesco
N1 - Funding Information:
This work was partially funded by Theme 6 of the EC seventh framework programme through the Marine Ecosystem Evolution in a Changing Environment (MEECE No. 212085 ) Collaborative Project.
PY - 2014/9
Y1 - 2014/9
N2 - Mollusc haemolymph proteins are known to play several important physiological roles in the immune system, heavy metal transport and the tissue distribution of lipophilic compounds. In this study, we analysed acetone-extracted proteins from mussel haemolymph by one- and two-dimensional gel electrophoresis. The proteins were identified by comparing mass spectrometry data with the invertebrate EST database, allowing us to establish the mussel haemolymph serum proteome. Extrapallial protein (EP) precursor represents the most abundant serum protein; astacin and CuZn superoxide dismutase were also detected. Slight contamination from muscle proteins, due to the sampling method, was also found. No differences were observed in the profiles obtained for male and female serum proteins. One aspect of interest was the previously reported finding that alkali-labile phosphate (ALP) from haemolymph serum may be representative of vitellogenin (vtg)-like protein content in the circulatory fluid of molluscs. In our analysis of mussel haemolymph serum, vitellogenin-like proteins were never found. To confirm these data, a typical methyl-tert-butyl-ether (MTBE) extraction, which is specific for vtg-like proteins, was performed, and the results of the electrophoretic analyses were compared with those obtained by acetonic precipitation. The results showed that the electrophoretic profiles are similar and that vtg-like proteins cannot be identified. Moreover, the main phosphoprotein present in female and male extracts is EP protein precursor. In addition, agarose gel electrophoresis demonstrates that high-molecular-weight forms of vtg-like proteins are not detectable.
AB - Mollusc haemolymph proteins are known to play several important physiological roles in the immune system, heavy metal transport and the tissue distribution of lipophilic compounds. In this study, we analysed acetone-extracted proteins from mussel haemolymph by one- and two-dimensional gel electrophoresis. The proteins were identified by comparing mass spectrometry data with the invertebrate EST database, allowing us to establish the mussel haemolymph serum proteome. Extrapallial protein (EP) precursor represents the most abundant serum protein; astacin and CuZn superoxide dismutase were also detected. Slight contamination from muscle proteins, due to the sampling method, was also found. No differences were observed in the profiles obtained for male and female serum proteins. One aspect of interest was the previously reported finding that alkali-labile phosphate (ALP) from haemolymph serum may be representative of vitellogenin (vtg)-like protein content in the circulatory fluid of molluscs. In our analysis of mussel haemolymph serum, vitellogenin-like proteins were never found. To confirm these data, a typical methyl-tert-butyl-ether (MTBE) extraction, which is specific for vtg-like proteins, was performed, and the results of the electrophoretic analyses were compared with those obtained by acetonic precipitation. The results showed that the electrophoretic profiles are similar and that vtg-like proteins cannot be identified. Moreover, the main phosphoprotein present in female and male extracts is EP protein precursor. In addition, agarose gel electrophoresis demonstrates that high-molecular-weight forms of vtg-like proteins are not detectable.
KW - Alkali-labile phosphate (ALP)
KW - Haemolymph serum
KW - Mytilus galloprovincialis
KW - Proteomics
KW - Vitellogenin (Vtg)-like proteins
UR - http://www.scopus.com/inward/record.url?scp=84905387990&partnerID=8YFLogxK
U2 - 10.1016/j.cbd.2014.07.003
DO - 10.1016/j.cbd.2014.07.003
M3 - Article
SN - 1744-117X
VL - 11
SP - 29
EP - 36
JO - Comparative Biochemistry and Physiology - Part D: Genomics and Proteomics
JF - Comparative Biochemistry and Physiology - Part D: Genomics and Proteomics
ER -