Hsp70 (HSPA1A) Human Active Protein

Background Info: Molecular weight of approximately 70kDa
ATPase active

Scientific Background: Hsp70 genes encode abundant heat-inducible 70-kDa hsps (hsp70s). In most eukaryotes hsp70 genes exist as part of a multigene family. They are found in most cellular compartments of eukaryotes including nuclei, mitochondria, chloroplasts, the endoplasmic reticulum and the cytosol, as well as in bacteria. The genes show a high degree of conservation, having at least 5O% identity (2). The N-terminal two thirds of hsp70s are more conserved than the C-terminal third. Hsp70 binds ATP with high affinity and possesses a weak ATPase activity which can be stimulated by binding to unfolded proteins and synthetic peptides (3). When hsc70 (constitutively expressed) present in mammalian cells was truncated, ATP binding activity was found to reside in an N-terminal fragment of 44kDa which lacked peptide binding capacity. Polypeptide binding ability therefore resided within the C-terminal half (4). The structure of this ATP binding domain displays multiple features of nucleotide binding proteins (5). All hsp70s, regardless of location, bind proteins, particularly unfolded ones. The molecular chaperones of the hsp70 family recognize and bind to nascent polypeptide chains as well as partially folded intermediates of proteins preventing their aggregation and misfolding. The binding of ATP triggers a critical conformational change leading to the release of the bound substrate protein (6). The universal ability of hsp70s to undergo cycles of binding to and release from hydrophobic stretches of partially unfolded proteins determines their role in a great variety of vital intracellular functions such as protein synthesis, protein folding and oligomerization and protein transport.

1. Zho, J. (1998). Cell 94: 471-480. 2. Boorstein, W. R., Ziegelhoffer, T. & Craig, E. A. (1993), J. Mol. Evol.38 (1) 1-17. 3. Rothman, J. (1989), Cell 59, 591 -601. 4. DeLuca-Flaherty et al. (1990), Cell 62, 875-887. 5. Bork, P., Sander, C. & Valencia, A. (1992), Proc. Nut1 Acad. Sci. USA 89, 7290-7294. 6. Fink, A.L. (1999) Physiol. Rev. 79: 425-449. 7. Smith, D.F., et al., (1993) Mol. Cell. Biol. 13(2):869-876. 8. Prapapanich, V., et al., (1996) Mol. Cell. Biol. 16(11):6200-6207. 9. Fernandez-Funez et al., (2000) Nature 408(6808):101-106.
1. Mizrahi, T., Heller, J., Goldenberg, S. and Arad, Z. (2010). Heat shock proteins and resistance to desiccation in congeneric land snails. Cell Stress & Chaperones. 15 (4), 351-363. doi: 10.1007/s12192-009-0150-9

2. Chanoux, R.A. et al. (2012). Hsp70 Promotes Epithelial Sodium Channel Functional Expression by Increasing Its Association with Coat Complex II and Its Exit from Endoplasmic Reticulum. The Journal of Biological Chemistry. 287. 19255-19265. doi: 10.1074/jbc.M112.357756

3. Mizrahi, T., Heller, J., Goldenberg, S. and Arad, Z. (2012). The heat shock response in congeneric land snails (Sphincterochila) from different habitats. Cell Stress and Chaperones. 17 (5), 639-645. doi: 10.1007/s12192-012-0340-8

Small volumes of HSPA1A active protein vial(s) may occasionally become entrapped in the seal of the product vial during shipment and storage. If necessary, briefly centrifuge the vial on a tabletop centrifuge to dislodge any liquid in the container`s cap. Certain products may require to ship with dry ice and additional dry ice fee may apply.

MBS806947 is an active protein targeting HSPA1A. Also known as Recombinant Human HSP70. Reactive in Human. Host: Human.