The discovery of stannin in rat dorsal root ganglia using an integrated proteohistological approach
© Humana Press Inc. 2004
The use of proteomic analysis to discover proteins (previously identified or unknown) in a tissue sample is a valuable tool. However, there is a limit to the extent one can validate a discovery with any single technology. In an effort to obviate this inherent constraint and to add value and dimension to protein profiling, we have coupled the information obtained through proteomic techniques with the validation provided by in situ hybridization and immunohistochemistry techniques. This approach can be illustrated by our efforts in the discovery of stannin in rat dorsal root ganglia (DRG). In this study, we initially used the Ciphergen ProteinChip® to perform protein profiling on the DRG of rats in a carrageenan-induced paw inflammation study. In an effort to discover new potential targets in inflammatory pain models, we profiled many potential peaks unique to the ipsilateral DRG of interest. One protein, found to bind to a hydrophobic chip at a molecular mass of 9500 Dalton, was preliminarily identified as stannin. To confirm its identification, we performed in situ hybridization and immunohistochemistry on the source DRG tissue to investigate the presence of stannin mRNA and protein expression, respectively. In addition to confirming the presence of stannin in these DRGs, we observed the upregulation of stannin in the DRGs over the course of carrageenan-induced inflammation, suggesting a possible role of stannin in inflammatory hyperalgesia. Taken together, these results illustrate the synergistic benefits of coupling 0 proteomic and histochemical techniques in identifying and validating targets and biomarkers for drug discovery.