Heat shock protein that is highly induced upon stress; plays a role in SRP-dependent cotranslational protein-membrane targeting and translocation; translocates to the nucleus under Cd2+ stress to mediate tolerance by regulating VHS1 expression; cytoplasmic protein that concentrates in nuclei upon starvation; member of the HSP70 family; SSA4 has a paralog, SSA3, that arose from the whole genome duplication