Metabolomic and transcriptomic analysis of the rice response to the bacterial blight pathogen Xanthomonas oryzae pv. oryzae.

Bacterial leaf blight (BLB), caused by Xanthomonas oryzae pv. oryzae (Xoo), gives rise to devastating crop losses in rice. Disease resistant rice cultivars are the most economical way to combat the disease.

Identification of substrates of human protein-tyrosine phosphatase PTPN22.

Stimulation of mature T cells activates a downstream signaling cascade involving temporally and spatially regulated phosphorylation and dephosphorylation events mediated by protein-tyrosine kinases and phosphatases, respectively. PTPN22 (Lyp), a non-receptor protein-tyrosine phosphatase, is expressed exclusively in cells of hematopoietic origin, notably in T cells where it represses signaling through the T cell receptor. We used substrate trapping coupled with mass spectrometry-based peptide identification in an unbiased approach to identify physiological substrates of PTPN22.

Simultaneous monitoring of multiple kinase activities by SELDI-TOF mass spectrometry.

Cellular response to the external environment is often controlled by one or more protein kinases. We report a methodology for simultaneously monitoring multiple kinase activities across multiple signal-transduction pathways using ProteinChip Array technology. Based on the addition of specific peptide reporters, kinase activity is detected by the presence of a mass shift of 80 Da (or multiple thereof) corresponding to the addition of one or more phosphate groups.