Table 1: Major prokaryotic and eukaryotic families of HSPs and their characteristics (see [15, 16]).

Hsp familyStructural featuresMembersIntracellular location

Small HSPsVaried, often large oligomeric structureshsp10, GroES, hsp16, α-crystallin, hsp20, hsp25, hsp26, hsp27Cytosol
HSP40Dimerichsp40, DnaJ, Sis1Cytosol
HSP47Monomer
Trimer
hsp47Endoplasmic reticulum (ER)
CCThetero-oligomeric complexTRiC (60 Kd family)cytosol
CalreticulinMonomericCalreticulin, CalnexinER
HSP602 stacked heptameric ringshsp60, hsp65, GroELCytosol
Mitochondria
HSP70Monomerichsp71, hsc70 (hsp73), hsp110/SSE, DnaK, SSC1, SSQ1, ECM10, Grp78 (BiP), Grp170Cytosol
Mitochondria
ER
HSP90Noncovalent homodimershsc84, hsp86, HTPG, Gp96 (Grp94, endoplasmin)Cytosol
ER
HSP100Multimeric complexes with hsp70 and hsp25hsp104, Hsp110, Clp proteins, Hsp78Cytosol
Mitochondria