Heat shock protein 27 and alpha B-crystallin can form a complex, which dissociates by heat shock.
We have previously demonstrated that in non-oncogenic adenovirus-transformed baby rat kidney cells a complex of hsp27 and a 22-kDa protein is present, which is lacking in oncogenic cells (Zantema, A., de Jong, E., Lardenoije, R., and van der Eb, A. J. (1989) J. Virol. 63, 3368-3375). Here we show that the 22-kDa protein is identical to alpha B-crystallin. The complex of hsp27 and alpha B-crystallin is also found in some other (non-transformed) cells. However, in most cells tested only hsp27 and no alpha B-crystallin is synthesized. Gel filtration studies show that both proteins are present almost exclusively in a 700-kDa complex. Heat treatment makes the complex fall apart, which is accompanied by a change in the conformation of alpha B-crystallin. Upon recovery, complexes are formed again from both pre-existing and newly synthesized proteins.
Zantema
A
A
Laboratory for Molecular Carcinogenesis, Sylvius Laboratory, Leiden, The Netherlands.
Verlaan-De Vries
M
M
Maasdam
D
D
Bol
S
S
van der Eb
A
A
D000818:Animals; D015153:Blotting, Western; D002461:Cell Line, Transformed; D002478:Cells, Cultured; D003459:Crystallins / Q000378:metabolism*; D006367:HeLa Cells; D006360:Heat-Shock Proteins / Q000378:metabolism*; D006358:Hot Temperature; D006801:Humans; D008970:Molecular Weight; D011233:Precipitin Tests
D003459:Crystallins; D006360:Heat-Shock Proteins