Proteomic Analysis of Gill Mucus from Grass Carp Ctenopharyngodon idella

Abstract

Fish gills is part of the first-line defense in fish. The proteome in gill mucus of grass carp (Ctenopharyngodon idella) was examined in this study. Two-dimensional polyacrylamide gel electrophoresis, in combination with size exclusion chromatography, was used to resolve the proteins. Two-dimensional maps of gill mucus revealed 406 distinct spots with Coomassie blue staining, of which 256 protein spots were subjected to identification using matrix-assisted laser desorption / ionization time-of-flight (MALDI-TOF), matrix-assisted laser desorption / ionization tandem mass spectrometry (MALDI-MS / MS) and liquid chromatography tandem mass spectrometry (LC-MS / MS). A total of 99 spots representing 52 proteins were identified, including 19 immune-related molecules such as lectin, interlectin, transferrin, and proteasome. Their presence in gill mucus may imply the importance of non-specific immunity in gill mucus. The present study provides the first picture on proteome in mucus of a fish species, and thus the foundation for understanding quantitative and qualitative variation in proteins in the mucus.