Anti-Heat Shock Protein 90, alpha (HSP90a)

The 90kD molecular chaperone family comprises several proteins including the 90kD heat shock protein, Hsp90 and the 94kD glucose-regulated protein, grp94 which are major molecular chaperones of the cytosol and of the endoplasmic reticulum. In mammalian cells there are at least two Hsp90 isoforms, Hsp90alpha and Hsp90beta which are encoded by separate genes. The amino acid sequence of human and yeast Hsp90alpha is 85% and 90% homologous to that of Hsp90beta respectively (3). All known members of the Hsp90 protein family are highly conserved, especially in the N-terminal and C-terminal regions which have been shown to contain independent chaperone sites with different substrate specificity (4,5). These ubiquitous and highly conserved proteins account for 1-2% of all cellular proteins in most cells. Hsp90 is part of the cell's powerful network of chaperones to fight the deleterious consequences of protein unfolding caused by non-physiological conditions. However, in the absence of stress, Hsp90 is a necessary component of fundamental cellular processes such as hormone signaling and cell cycle control. In this context several key regulatory proteins such as steroid receptors, cell cycle kinases involved in signal transduction and p53 have been identified as substrates of Hsp90 (6). It has been suggested that Hsp90 acts as a capacitor for morphological evolution by buffering widespread variation, which may affect morphogenic pathways. Recent studies indicate that when Drosophila Hsp90 buffering is compromised by e.g., temperature, cryptic variants are expressed and selection can lead to the continued expression of these traits, even if Hsp90 function is restored (7). Applications: Suitable for use in Western Blot and Immunohistochemistry. Other applications not tested. Recommended Dilution: Western Blot (Colorimetric): 1:1000, Optimal dilutions to be determined by researcher. Positive Controls: Recombinant Human Hsp90alpha Protein, HeLa Heat Shocked Cell Lysate, Storage and Stability: May be stored at 4°C for short-term only. Aliquot to avoid repeated freezing and thawing. Store at -20°C. Aliquots are stable for 12 months after receipt. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.