CELLULAR-LOCALIZATION OF HIGH-MOLECULAR-MASS HEAT-SHOCK PROTEINS IN MURINE CELLS

We have previously prepared an antiserum raised against hsp105 of muri ne FM3A cells. The anti-hsp105 serum reacted to two isoforms of high m olecular-mass heat shock protein (HMM-HSP) having a molecular mass of 105,000 Da (hsp105A and hsp105B) in FM3A cells. While hsp105A and hsp1 05B were both synthesized and accumulated under non-stressed condition s, upon exposure to heat shock much more hsp105B was induced than hsp1 05A. When the cellular distribution of these hsp105s in murine 3T3 Swi ss albino and C3H 10T1/2 cells was examined by immunofluorescence meth ods using the anti-hsp105 serum, the HMM-HSPs were localized in the cy toplasm and nuclei and were never found in the nucleoli of both 3T3 an d C3H cells under non-stressed and stressed conditions. (C) 1994 Acade mic Press, Inc.