Two-dimensional gel electrophoresis (2DE) and matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS) were used for proteome analysis on heat stress-induced apoptosis in Jurakat cells of a human T lymphoblastic leukemia cell line. The heat-stress was given by incubating cells for 30 min at 43 C up to 49 C in a serum free culture medium. Intracellular soluble proteins were extracted from the cells immediately after the incubation and submitted to 2DE. Stathmin phosphorylated forms, calmodulin, protein kinase C substrate and thymosin beta-4 were increased in temperature dependent manner although heat shok protein 70 was not increased by the incubation. On the other hand, ubiquitin-like protein SMT3B, eukaryote translation initiation factor-5A and -3 subunit, Rho GDP-dissociation inhibitor 1, and protein phosphatase 2C were significantly decreased. Further examinations by MALDI/MS/MS more showed that the temperature dependent phosphorylation of stathmin was initially occured at Ser37 specific site for CDK-1 and followed by phosphorylation at Ser24 for CDK-1/MAPK or Ser15 for PKA at higher temperature.
