Quantitative phosphoproteomic analyses provide evidence for extensive phosphorylation of regulatory proteins in the rhizobia–legume symbiosis

Key message Symbiotic nitrogen fixation in root nodules of grain legumes is essential for high yielding. Protein phosphorylation/dephosphorylation plays important role in root nodule development. Differences in the phosphoproteomes may either be developmental specific and related to nitrogen fixation activity. An iTRAQ-based quantitative phosphoproteomic analyses during nodule development enables identification of specific phosphorylation signaling in the Lotus–rhizobia symbiosis.