Steroid receptors are ligand-dependent intracellular proteins that stimulate transcription of specific genes by binding to specific DNA sequences following activation by the appropriate hormone. Prior to activation, steroid receptors associate with a number of different proteins in both a stable and transient fashion. Steroid receptor complex proteins include heat shock proteins (HSP90, HSP70), immunosuppressant binding proteins called immunophilins (the FK506 binding proteins, FKBP52 & FKBP54 and the cyclosporin binding protein, CyP-40) and three other proteins termed p23, p60 and heat shock cognate protein 70kD (HSC70)-interacting protein (Hip), also known as p48. Hip, along with HSP70 and p60, combine with steroid receptors as transient intermediate complex members.
In vitro studies have suggested that Hip transiently interacts with progesterone receptor in a cell free system prior to hormone binding competency and dissociates from the receptor complex with the binding of an HSP90:Immunophilin:p23 subcomplex which then results in a hormone-binding-competent receptor complex. While neither its exact function nor mechanism of action have been identified, Hip appears to be an important factor in steroid receptor function. Hip also appears to regulate the function of HSC70 in an ATP hydrolysis and HSP40 dependent fashion.
Cellular Localization: Cytoplasmic
Suitable for use in Western Blot and Immunoprecipitation. Other applications not tested.
Optimal dilutions to be determined by the researcher.
Storage and Stability:
May be stored at 4 degrees C for short-term only. For long-term storage and to avoid repeated freezing and thawing, aliquot Store at -20 degrees C. Aliquots are stable for at least 12 months at -20 degrees C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.