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HSPH1 analysis is used as an indicator and as a diagnostic aid in problematic lesions. HSPH1 chaperones the responses to endoplasmic reticulum (ER) stress during its interactions with GRP78 and GSK3, and without HSP105 cell death following ER stress proceeds by a non-caspase-3-dependent process. HSPH1 is highly expressed in a variety of human tumors. HSPH1 is a mammalian member of the HSP105/110 family, a diverged subgroup of the HSP70 family. HSP105 has 2 isoforms, alpha and beta. Hsp105a associates with Hsp70/Hsc70 as complexes in vivo and regulates the chaperone activity of Hsp70/Hsc70 negatively in vitro and in vivo.

Binding immunoglobulin protein (BiP or HSPA5) is a member of the family of ~70kDa heat shock proteins (HSP 70). HSPA5 is a stress response protein which is induced by agents or conditions that adversely affect endoplasmic reticulum (ER) function. HSPA5 is crucial for the proper glycosylation, folding as well as for the maintenance of cell homeostasis and the prevention of apoptosis.

HSP27 (also known as the Estrogen-Regulated 24K protein, and hsp 28) is a member of the mammalian small heat shock protein family. Hsp27 is expressed constitutively in many tissues and its expression is increased to high levels after various types of stress including elevated temperatures, toxic metals, drugs and oxidants. Also, Hsp27 is phosphorylated in vivo on three phosphorylation sites (Ser15, Ser78 and Ser82) by protein kinases including MAPKAP kinase 2 and the stress-activated protein kinase SAPK2 (p38).

HSPA13 belongs to the heat shock protein 70 family and is related to microsomes. Members of this protein family take part in the processing of cytosolic and secretory proteins, in addition to the exclusion of denatured or incorrectly-folded proteins. HSPA13 is known to cooperate with PLIC-1 and PLIC-2, proteins which have a role in the signaling connection between the membrane receptors for thrombospondin and the cytoskeleton

HSP70 is a human heat shock protein. HSP-70 is an important part of the cell''s machinery for protein folding, and help to protect cells from stress. In most species, there are many proteins that belong to the HSP70 family. Some of these are only expressed under stress conditions, while some are present in cells under normal growth conditions and are not heat-inducible. They can be found in different cellular compartments (nuclear, cytosolic, mitochondrial, endoplasmic reticulum, etc...).

The transcription of heat-shock genes is rapidly induced after temperature stress in response to environmental changes, and it is also involved in oogenesis, spermatogenesis, and placental development. Hsp90, is a major repressor of HSF1 gene. HSF1 is known for its participation in heat shock response. HSF1 protein regulates the transcription of hundreds of targets, such as genes involved in protein folding, detoxification, energy generation, carbohydrate metabolism, and cell wall organization. HSF1 binds to MTA1 in vitro & in breast carcinoma. Suppression of estrogen-dependent transcription may contribute to role of HSF1 in cancer. Human cancer lines of diverse origins express higher dependence on HSF1 function to maintain proliferation and survival than their non-transformed counterparts. HSF1 induces anticoagulation and relaxation factors in vascular endothelial cells and could therefore be used to treat cardiovascular disease. HSF1 is directly involved in the regulation of HO1 havi

HSP90B1 is an abundant molecular chaperone resident endoplasmic reticulum (ER) lumenal stress protein which is part of the Hsp90 family. HSP90B1 is involved in maintaining protein homeostasis in the secretory pathway as well as functioning in the intracellular trafficking of peptides from the extracellular space to the MHC class I antigen processing pathway of antigen presentation cells. HSP90B1 has key roles in signal transduction, protein folding, protein degradation, and morphologic evolution. HSP90B1 protein associates with numerous cochaperones and involved in folding of newly synthesized proteins or stabilizing and refolding denatured proteins after stress. HSP90B1 is highly expressed in human gastric carcinoma BGC-823 cells during the whole cell cycle.

HSP90 has been identified in the cytosol, nucleus and endoplasmic reticulum, and is reported to exist in many tissue types. In several tissues, including smooth muscle, HSP90 comprises up to 2% of total cellular protein. HSP90 functions as a dimer, assembled as part of heterocomplex. It possesses ATP-binding site and low ATPase activity. HSP90 is able to associate with actin filaments in certain conditions. Another important property of HSP90 is the binding of unoccupied steroid hormone receptors. HSP90 has been characterized as a molecular chaperone able to keep the target protein in a folding-competent state. It has an enhanced chaperone activity in oligomeric form at high temperatures. HSP90 function is sensitive to bivalent cations concentration.

HSP90B1 is an abundant molecular chaperone resident endoplasmic reticulum (ER) lumenal stress protein which is part of the Hsp90 family. HSP90B1 is involved in maintaining protein homeostasis in the secretory pathway as well as functioning in the intracellular trafficking of peptides from the extracellular space to the MHC class I antigen processing pathway of antigen presentation cells. HSP90B1 has key roles in signal transduction, protein folding, protein degradation, and morphologic evolution. HSP90B1 protein associates with numerous cochaperones and involved in folding of newly synthesized proteins or stabilizing and refolding denatured proteins after stress. HSP90B1 is highly expressed in human gastric carcinoma BGC-823 cells during the whole cell cycle.

Alpha crystallins are composed of two gene products ; alpha-A and alpha-B, for acidic and basic, respectively. Alpha crystallins can be induced by heat shock and are members of the small heat shock protein (sHSP also known as the HSP20). They act as molecular chaperones and hold them in large soluble aggregates. These heterogeneous aggregates consist of 30-40 subunits; the alpha-A and alpha-B subunits have a 3:1 ratio, respectively. Two additional function of -crystallins are an autokinase activity and participation in the intracellular architecture. The expression of alpha-A is preferentially restricted to the lens cell.

Human HSP40 (heat shock protein with molecular size of 40kDa) is one of the mammalian homologues of bacterial DnaJ heat shock protein and regulates cellular processes by aiding in the folding, transport and assembly. HSP40 protein contains the J-domain which controls interaction with the ATPase domain of DnaK.

AHA1 is a cochaperone that stimulates hsp90 ATPase activity. AHSA1 binds the middle domain of Hsp90 (amino acid 272-627) and functions as an ATPase-activating protein that competes with p23 and other co-chaperones for Hsp90 binding.
AHA1 affects a step in the endoplasmic reticulum to golgi trafficking.

Alpha crystallins are composed of two gene products; alpha-A and alpha-B, for acidic and basic, respectively. Alpha crystallins can be induced by heat shock and are members of the small heat shock protein (sHSP also known as the HSP20). They act as molecular chaperones and hold them in in large soluble aggregates. These heterogeneous aggregates consist of 30-40 subunits; the alpha-A and alpha-B subunits have a 3:1 ratio, respectively. Two additional function of -crystallins are an autokinase activity and participation in the intracellular architecture. Alpha-B is expressed widely in many tissues and organs and occurs in many neurological diseases.

Binding immunoglobulin protein (BiP or HSPA5) is a member of the family of ~70kDa heat shock proteins (HSP 70). HSPA5 is a stress response protein which is induced by agents or conditions that adversely affect endoplasmic reticulum (ER) function. HSPA5 is crucial for the proper glycosylation, folding as well as for the maintenance of cell homeostasis and the prevention of apoptosis.

GroEL, HSP60 is a chaperonin located in the mitochondria which is responsible for the transportation & refolding of proteins from the cytoplasm directly into the mitochondrial matrix. GroEL is regulated by the HSP10 cochaperonin, which is a single heptameric protein ring having a molecular mass of 10 kDa which form a unique complex with HSP60. HSP10, GroES coordinates the ATPase activity of the HSP60 subunits in order to allow the release of bound polypeptide in a manner that is productive for its correct folding.

ST13 is an adaptor protein (co-chaperone) that mediates the association of HSP70 & HSP90 and appears in early receptor complexes. ST13 plays a role in the assembly process of glucocorticoid receptor, which requires the assistance of multiple molecular chaperones. The expression of ST13 is downregulated in colorectal carcinoma tissue signifying that is candidate tumor suppressor gene. Through common binding to both Hsp70 and Hsp90, ST13 functions as an adaptor that can integrate Hsp70 and Hsp90 interactions. The expression of ST13 decreases in colorectal cancer tissue compared with that in adjacent normal tissue. ST13 is mostly expressed in colorectal epithelia and adenocarcinoma cells. ST13 functions to promote the efficiency of glucocorticoid receptor maturation in cells. The expression levels of the ST13 gene were significantly decreased in primary tumors compared with adjacent mucosa.

HSPB3 is a muscle-specific small heat shock protein which is expressed specially in heart and skeletal muscle. Mammalian small heat shock proteins (sHSP) are highly expressed proteins with varied roles, including the assembly and impounding of multi-protein complexes, transportation of nascent polypeptide chains thru cellular membranes and regulation of protein folding. HSPB3 perform as an ATP-dependent chaperone protein which takes part in the refolding of denatured proteins and inhibition of actin polymerization.

ST13 is an adaptor protein (co-chaperone) that mediates the association of HSP70 & HSP90 and appears in early receptor complexes. ST13 plays a role in the assembly process of glucocorticoid receptor, which requires the assistance of multiple molecular chaperones. The expression of ST13 is downregulated in colorectal carcinoma tissue signifying that is candidate tumor suppressor gene. Through common binding to both Hsp70 and Hsp90, ST13 functions as an adaptor that can integrate Hsp70 and Hsp90 interactions. The expression of ST13 decreases in colorectal cancer tissue compared with that in adjacent normal tissue. ST13 is mostly expressed in colorectal epithelia and adenocarcinoma cells. ST13 functions to promote the efficiency of glucocorticoid receptor maturation in cells. The expression levels of the ST13 gene were significantly decreased in primary tumors compared with adjacent mucosa.

Once Chinese hamster K12 cells are starved from glucose, the synthesis of GRP (glucose-regulated protein) expressed. HSPA5 also called BiP, is part of the HSP70 family and plays a role in the folding and assembly of proteins in the endoplasmic reticulum. HSPA5 plays a key role in monitoring protein transport through the cell.
HSPA5 is a stress response protein which is induced by agents or conditions that adversely affect endoplasmic reticulum function. HSPA5 is crucial for the proper glycosylation, folding as well as for the maintenance of cell homeostasis and the prevention of apoptosis. HSPA5 is differentially expressed in the dorsolateral prefrontal cortex from patients with schizophrenia. HSPA5 guides posttranslational hepatitis B virus large envelope protein import into the mammalian ER. HSPA5 actively regulates multiple malignant phenotypes, including cell growth, migration, and invasion.

The heat-shock response is elicited by exposure of cells to thermal and chemical stress and through the activation of HSFs (heat shock factors) results in the elevated expression of heat-shock induced genes. Heat shock factor binding protein-1 (HSBP1), is a 76-amino-acid protein that binds to heat shock factor 1(HSF1), which is a transcription factor involved in the HS response. During HS response, HSF1 undergoes conformational transition from an inert non-DNA-binding monomer to active functional trimers. HSBP1 is nuclear-localized and interacts with the active trimeric state of HSF1 to negatively regulate HSF1 DNA-binding activity. Overexpression of HSBP1 in mammalian cells represses the transactivation activity of HSF1. When overexpressed in C.elegans HSBP1 has severe effects on survival of the animals after thermal and chemical stress consistent with a role of HSBP1 as a negative regulator of heat shock response.

HSPBAP1 holds a jumonji C (JMJC) domain. HSPBAP1 protein has a part in regulating stress response in the living cell. HSPBAP1 is known to interact with CRYAB and HSPB1.

HSPB7 is part of the Heat shock protein beta family. The HSPB family is one of the more diverse families within the group of HSP families. Several members have chaperone-like activities and/or participate in cytoskeletal stabilization. Several members also show a dynamic, stress-induced translocation to SC35 splicing speckles. HSPB7 constitutively localized to SC35 splicing speckles, determined by its N-terminus. HSPB7 does not support refolding though HSPB1 and HSPB5 chaperone heat unfolded substrates and keet them folding competent.

HSPB8 displays temperature-dependent chaperone activity. HSPB8 acts as a mn(2+)-dependent serine-threonine- specific protein kinase. we are not convinced that this is its true role. Defects in HSPB8 are a cause of distal hereditary motor neuropathy type ii (DHMN2) also known as distal spinal muscular atrophy (DSMA) and spinal muscular atrophy of the charcot-marie-tooth type. it is an autosomal dominant disorder of lower motor neurons characterized by distal muscle weakness.

HSPA9 is part of the heat shock protein 70 family which contains both heat-inducible and constitutively expressed members that are also called heat-shock cognate proteins. HSPA9 encodes a heat-shock cognate protein that is involved in the control of cell proliferation and acts as a chaperone. HSPA9 was restricted to chromosome 5, band q31, a region that is often deleted in myeloid leukemias and myelodysplasia (MDS), making it a candidate tumor suppressor gene, which is consistent with the biological function of its murine homologue. HSPA9 supresses nuclear translocation, transcriptional activation, and control of centrosome-duplication functions of p53.