The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)
 

Links

 

Gene Review

SSA2  -  Hsp70 family chaperone SSA2

Saccharomyces cerevisiae S288c

Synonyms: Heat shock protein SSA2, L0931, YLL024C
 
 
Welcome! If you are familiar with the subject of this article, you can contribute to this open access knowledge base by deleting incorrect information, restructuring or completely rewriting any text. Read more.
 

High impact information on SSA2

  • The heat shock protein Ssa2p was identified as one of the ATP binding proteins involved in FBPase import [1].
  • In contrast, we find that constitutive overexpression of SSA1 but not SSA2 cured cells of [URE3], uncovering a specific interaction between Ssa1p and [URE3] and a functional distinction between these nearly identical Hsp70 isoforms [2].
  • SSA3, like SSA4, is a heat-inducible gene that is not normally expressed at 23 degrees C. Nevertheless, an intact copy of SSA3 regulated by the constitutive SSA2 promoter was capable of rescuing a ssa1 ssa2 ssa4 strain [3].
  • The SSA4 isoenzyme, which is produced only under stress conditions, has an uncoating activity intermediate between SSA1 and SSA2 [4].
  • Using hsp70 mutant yeast strains we find a marked difference in uncoating activity between the SSA1 and SSA2 isoenzymes, although there is only a 3% difference between their amino acid sequences [4].
 

Biological context of SSA2

  • One subfamily, identified by sequence homology, contains four genes, SSA1, SSA2, SSA3, and SSA4 (formerly YG100, YG102, YG106, and YG107, respectively) [3].
  • In a separate experiment, overexpression of SSA2, a member of the Hsp70 family and a prominent candidate for the feedback regulation of HSF, did not inhibit the heat shock response [5].
  • Each chimeric gene was composed of promoter and N-terminal coding regions from the yeast SSA1 or SSA2 genes fused in-frame to the lac operon [6].
 

Other interactions of SSA2

  • This finding contrasted with the SSA1-SSA2 pattern observed during growth to stationary phase [7].
  • After the shift of the cdc15-2 strain from 37 degrees C to 25 degrees C, 54 mRNAs were altered in translation state, including the products of the stress genes HSP82, HSC82, and SSA2 [8].
  • Two such destabilized mRNAs, from the SSA1 and SSA2 genes, have been identified using temperature-sensitive mutations affecting the Prt1 component of eukaryotic initiation factor 3 [9].

References

  1. The heat shock protein Ssa2p is required for import of fructose-1, 6-bisphosphatase into Vid vesicles. Brown, C.R., McCann, J.A., Chiang, H.L. J. Cell Biol. (2000) [Pubmed]
  2. Antagonistic interactions between yeast [PSI(+)] and [URE3] prions and curing of [URE3] by Hsp70 protein chaperone Ssa1p but not by Ssa2p. Schwimmer, C., Masison, D.C. Mol. Cell. Biol. (2002) [Pubmed]
  3. Complex interactions among members of an essential subfamily of hsp70 genes in Saccharomyces cerevisiae. Werner-Washburne, M., Stone, D.E., Craig, E.A. Mol. Cell. Biol. (1987) [Pubmed]
  4. Uncoating of coated vesicles by yeast hsp70 proteins. Gao, B.C., Biosca, J., Craig, E.A., Greene, L.E., Eisenberg, E. J. Biol. Chem. (1991) [Pubmed]
  5. Activation of heat shock transcription factor in yeast is not influenced by the levels of expression of heat shock proteins. Hjorth-Sørensen, B., Hoffmann, E.R., Lissin, N.M., Sewell, A.K., Jakobsen, B.K. Mol. Microbiol. (2001) [Pubmed]
  6. Expression of lacZ gene fusions affects downstream transcription in yeast. Barnes, C.A., Johnston, G.C., Singer, R.A. Gene (1991) [Pubmed]
  7. Yeast Hsp70 RNA levels vary in response to the physiological status of the cell. Werner-Washburne, M., Becker, J., Kosic-Smithers, J., Craig, E.A. J. Bacteriol. (1989) [Pubmed]
  8. The transcriptome and its translation during recovery from cell cycle arrest in Saccharomyces cerevisiae. Serikawa, K.A., Xu, X.L., MacKay, V.L., Law, G.L., Zong, Q., Zhao, L.P., Bumgarner, R., Morris, D.R. Mol. Cell Proteomics (2003) [Pubmed]
  9. Upf1 and Upf2 proteins mediate normal yeast mRNA degradation when translation initiation is limited. Barnes, C.A. Nucleic Acids Res. (1998) [Pubmed]
 
WikiGenes - Universities