Analysis of Sparassis latifolia Proteomes at the Early Fruiting and Fruiting Stages of Mushroom Development Using iTRAQ-coupled 2D LC-MS/MS

Protein expression at different developmental stages of Sparassis latifolia has been investigated using Isobaric Tags for Relative and Absolute Quantification (iTRAQ)-coupled 2D LC-MS/MS (two-dimensional liquid chromatography tandem mass spectrometry).A total of 2305 reliable proteins were identified using the Q-Exactive mass spectrometry and the ProteinPilot search engines,and 2219 of these proteins had a quantitative dimension.Of the quantitatively different proteins,104 were significantly up-regulated and 142 down-regulated at the early fruiting stage (80 days following inoculation),and 155 were significantly upregulated and 460 down-regulated at the fruiting stage (115 days following inoculation),compared with the primordium stage (60 days following inoculation),respectively.Data from gene ontology (GO) molecular functional analysis revealed that the differentially expressed proteins were mainly involved in catalytic activity,protein binding and hydrolase activity.Significantly enriched KEGG pathways included those related to carbon metabolism,biosynthesis of amino acids,ribosome pathways and glycolysis/gluconeogenesis.Furthermore,the numbers of differentially expressed proteins related to signal transmission and transcription factors were 27 and 7,respectively.iTRAQ-coupled 2D LC-MS/MS methodology was highly effective in isolating and identifying protein groups in S.latifolia,and could promote a better understanding of the developmental molecular mechanisms operative in this and other fungi.