Hsp Familya Hsp Structure and Function References
sHsps Multimeric complexes composed of monomers containing an amino-termial region, an α-crystallin domain and a carboxyl-extension; the domains cooperate in oligomerization and substrate binding.
Prevent stress-induced  irreversible protein
denaturation;  inhibit apoptosis; ATP independent.
Hsp70 Monomeric protein with a conserved ATP binding /hydrolysis site in the amino-terminus, a linker region and a variable carboxyl substrate-binding domain.
Binds and folds nascent and denaturing proteins; protects against stresses such as bacterial infection.
Hsp90 Dimeric protein; each monomer has an amino-terminal domain that hydrolyzes ATP, a substrate–binding middle domain and a carboxyl-domain that interacts with co-chaperones.
Folds nascent and denaturing proteins; interacts with kinases and other regulatory molecules; protein degradation.
Hsp60 (chaperonin, TRiC, CCT) Two back-to-back rings of eight to nine subunits each with an apical capped domain that binds substrate, an equatorial region with an ATP hydrolysis site and a linking domain.
Binds substrates via hydrophobic, polar and charged residues; required by actin and tubulin for folding.
aThe Hsps are described separately but they function as co-operative networks to maintain protein homeostasis within cells, either during normal growth or upon exposure to stress such as heat, salinity, toxins and infection.
Table 1: The structure and function of Hsps involved in diseases of aquatic organisms