The Heat Shock Protein 70s (Hsp70s) are an essential family of proteins involved in folding of new proteins and triaging of damaged proteins for proteasomal-mediated degradation. They are highly conserved in all organisms, with each organism possessing multiple highly similar Hsp70 variants (isoforms). These isoforms have been previously thought to be identical in function differing only in their spatio-temporal expression pattern. The model organism Saccharomyces cerevisiae (baker’s yeast) expresses four Hsp70 isoforms Ssa1, 2, 3 and 4. Here, we review recent findings that suggest that despite their similarity, Ssa isoforms may have unique cellular functions.
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This work was supported by NCI R15CA208773 (AWT).
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Communicated by M. Kupiec.
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Lotz, S.K., Knighton, L.E., Nitika et al. Not quite the SSAme: unique roles for the yeast cytosolic Hsp70s. Curr Genet 65, 1127–1134 (2019). https://doi.org/10.1007/s00294-019-00978-8