NORRIS, J*; KINTER, M; KAVETI, S; NIEWIAROWSKI, P H; LONDRAVILLE, R L; University of Akron; Cleveland Clinic Foundation; Cleveland Clinic Foundation; University of Akron; University of Akron: Brain Proteome of Fence Lizard is Relatively Refractory to Seasonal Changes in Protein Expression

The brain proteome of Sceloporus undulatus was analyzed in its response to seasonal acclimatization. S. undulatus undergoes dramatic changes in behavior and physiology as it enters and emerges from overwinter hibernation. We extracted total brain protein from a Nebraska population of S. undulatus collected before they entered (9/04) and after they left (7/04) hibernation. Total protein was separated by 2-dimensional electrophoresis (pI 4-7, 15%) and homologous bands analyzed for relative staining density between seasons (n=5 for Fall, 4 for Spring). Bands of interest were excised from the gel and analyzed by mass spectrometry (trypsin digestion, ESI-LC-Ms/MS(ITD), CID, MALDI-TOF). The resulting spectra were used to search against non-redundant databases using MASCOT, SEQUEST and BLAST in order to identify proteins. We have positively identified over 10 proteins, including synuclein, fatty acid-binding protein, alpha enolase and aldolase C. All of the bands identified to date vary less than 2-fold between seasons. This is in contrast to response of the liver proteome, which includes proteins that vary ~14-fold between seasons. In addition, total bands detected (~700) is not different between seasons in brain, but is different in liver. We postulate that the centrally regulated physiological changes in behavior and physiology that are mediated by the brain (e.g. wholesale changes in metabolic rate) are generally not accompanied by large changes in expression of protein.