DIFFERENT PEPTIDE BINDING SPECIFICITIES OF HSP70 FAMILY MEMBERS

A set of heptapeptides was used to compare the relative peptide affini ties of three proteins of the hsp70 family: bacterial DnaK, mammalian cytosolic hsc70, and BiP from mammalian ER. Each hsp displays a charac teristic pattern of relative affinities. DnaK and hsc70 are more simil ar to each other than to BiP. A difference in peptide binding specific ity may be an important determinant in adjusting an hsp70 family membe r to its particular cellular function.