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HSP10 is part of the molecular chaperons, that are crucial for thir efficient folding of proteins in normal as well as stress conditions. GroES function is to bind to HSP60 in the presence of ATP, thus causing a change in the HSP60 conformation & enclosing the protein substrate within the complex. ATP hydrolysis by chaperonin-60 which destabilizes the HSP10-HSP60 complex, thereby allowing it to dissociate and secrete the substrate protein.
GroES having the NCBI accession number of NP_002148 was purified by using conventional chromatography techniques.

DDIT3 reduces DNA-binding activity of C/EBP and lap by forming heterodimers which don’t bind DNA. DDIT3, also known as GADD153, is a basic domain-leucine zipper(bZIP) transcription factor of C/EBP family. DDIT3 protein is up-regulated by several stresses, such as amino acid or glucose starvation, endoplasmic reticulum (ER) stress, osmotic stress and hypoxia. DDIT3 protein is invloved in ER stress-mediated apoptosis and in disease including diabetes, brain ischemia and neurodegenerative disease. DDIT3 plays a role in asoprisnil-induced apoptosis. Hypoglycaemia-induced necrotic cell death of neuroblastoma cells is an active process mediated via the induction of the transcription factor DDIT3. DDIT3 plays an important role in melanoma progression. HRG stimulation of mammary epithelial cells induces the expression of DDIT3 mRNA and protein and transcription of DDIT3 promoter.

Insulin-like growth factor-binding protein 4 (IGFBP-4) is a part of the insulin-like growth factor binding protein (IGFBP) family. IGFBP4 includes an IGFBP domain and a thyroglobulin type-I domain. IGFBP4 binds both insulin-like growth factors (IGFs) I and II. IGFBP-4 circulates in the plasma in both glycosylated and non-glycosylated forms. IGFBPs can either inhibit or enhance the biological activities of IGF, or act in an IGF independent manner. IGFBP-4 is consistently inhibits several cancer cells in vivo and in vitro, suggesting that it may function as an apoptotic factor. IGFBP4 is produced by all colon cancer cells. Binding of IGFBP-4 prolongs the half-life of the IGFs and changes their interaction with cell surface receptors.

Platelet factor-4 is a 70-amino acid protein that is released from the alpha-granules of activated platelets.PF4’s major physiologic role appears to be neutralization of molecules on the endothelial surface of blood vessels, thereby inhibiting local antithrombin III activity and promoting coagulation. As a strong chemoattractant for neutrophils and fibroblasts, PF4 probably has a role in inflammation and wound repair. Oncostatin-A is a member of the CXC chemokine family. Furthermore, it is used as an inhibitor in the angiogenesis during tumor therapy.

Melanoregulin (MREG) takes part in membrane fusion and in regulating the biogenesis of disk membranes of photoreceptor rods. MREG is expressed in photoreceptor cells as two isoforms as a result of alternative splicing. MREG interacts with Peripherin-2, a photoreceptor specific tetraspanin protein which is required to preserve normal cell structure during the renewal process of membrane fusion. Moreover, MREG plays a part in the incorporation of pigments into hair.

CFD is an important component of the alternative pathway of complement activation. CFD cleaves and activates factor B when it binds C3b or a C3b-like protein such as C3 or CVF. CFD is a serine protease that exists as a mature protease, but it exhibits a highly restricted specificity and it appears to be substrate activated. CFD cleaves factor B bound to C3b leading to the release of the Ba fragment and leaving the Bb fragment bound to C3b. The C3b,Bb complex is called a C3 or C5 convertase because it converts these proteins to their active forms by cleaving off the small peptides C3a and C5a, respectively.

NADH dehydrogenase [ubiquinone] 1 alpha subcomplex assembly factor 4 (NDUFAF4) is involved in the compilation of mitochondrial NADH: ubiquinone oxidoreductase complex (complex I). In addition, NDUFAF4 is involved in cell proliferation and survival of hormone-dependent tumor cells. NDUFAF4 may also be a regulator of breast tumor cell invasion. NDUFAF4 gene mutations cause the mitochondrial complex I deficiency.

Placental Lactogen is a polypeptide hormone that is produced by the Syncytiotrophoblasts of the Placenta.Placental Lactogen has both GH and Prolactin activities on growth, lactation, and luteal steroid production. In women, placental lactogen secretion begins soon after implantation and increases to 1 g or more a day in late pregnancy. Placental Lactogen Bovine is also capable of activating human and other heterologous GH receptors.

Endothelial cells express three different vascular endothelial growth factor (VEGF) receptors, belonging to the family of receptor tyrosine kinases (RTKs). They are named VEGFR-1 (Flt-1), VEGFR-2 (KDR/Flk-1), VEGFR-3 (Flt-4). Their expression is almost exclusively restricted to endothelial cells, but VEGFR-1 can also be found on monocytes, dendritic cells and on trophoblast cells. The flt-1 gene was first described in 1990. The receptor contains seven immunoglobulin-like extracellular domains, a single transmembrane region and an intracellular splited tyrosine kinase domain. Compared to VEGFR-2 the Flt-1 receptor has a higher affinity for VEGF but a weaker signaling activity. VEGFR-1 thus leads not to proliferation of endothelial cells, but mediates signals for differentiation. Interestingly a naturally occuring soluble variant of VEGFR-1 (sVEGFR-1) was found in HUVE supernatants in 1996, which is generated by alternative splicing of the flt-1 mRNA. The biological functions of sVEGFR-1 still are not clear, but it seems to be an endogenous regulator of angiogenesis, binding VEGF with the same affinity as the full-length receptor.

Endothelial cells express three different vascular endothelial growth factor (VEGF) receptors, belonging to the family of receptor tyrosine kinases (RTKs). They are named VEGFR-1 (Flt-1), VEGFR-2 (KDR/Flk-1), VEGFR-3 (Flt-4). Their expression is almost exclusively restricted to endothelial cells, but VEGFR-1 can also be found on monocytes, dendritic cells and on trophoblast cells. The flt-1 gene was first described in 1990. The receptor contains seven immunoglobulin-like extracellular domains, a single transmembrane region and an intracellular splited tyrosine kinase domain. Compared to VEGFR-2 the Flt-1 receptor has a higher affinity for VEGF but a weaker signaling activity. VEGFR-1 thus leads not to proliferation of endothelial cells, but mediates signals for differentiation. Interestingly a naturally occuring soluble variant of VEGFR-1 (sVEGFR-1) was found in HUVE supernatants in 1996, which is generated by alternative splicing of the flt-1 mRNA. The biological functions of sVEGFR-1 still are not clear, but it seems to be an endogenous regulator of angiogenesis, binding VEGF with the same affinity as the full-length receptor.

A 16-kDa peptide hormone secreted from white adipocytes and implicated in the regulation of food intake and energy balance. Leptin provides the key afferent signal from fat cells in the feedback system that controls body fat stores.

IL4 is a pleiotropic cytokine produced by activated T cells. IL4 is a ligand for interleukin 4 receptor. The interleukin 4 receptor also binds to IL13, which may contribute to many overlapping functions of this cytokine and IL13. STAT6, a signal transducer and activator of transcription, has been shown to play a central role in mediating the immune regulatory signal of this cytokine. This gene, IL3, IL5, IL13, and CSF2 form a cytokine gene cluster on chromosome 5q, with this gene particularly close to IL13. IL4, IL13 and IL5 are found to be regulated coordinately by several long-range regulatory elements in an over 120 kilobase range on the chromosome. Two alternatively spliced transcript variants of this gene encoding distinct isoforms have been reported.

Polymerase II Polypeptide F (POLR2F) is the 6th largest subunit of RNA polymerase II, the polymerase responsible for synthesizing messenger RNA in eukaryotes, which is also shared by the other two DNA-directed RNA polymerases. In yeast, POLR2F, in combination with at least 2 other subunits, forms a structure which stabilizes the transcribing polymerase on the DNA template. DNA-dependent RNA polymerases catalyze the transcription of DNA into RNA via the 4 ribonucleoside triphosphates as substrates. Pol II is the principal element of the basal RNA polymerase II transcription apparatus. Pols are comprised of mobile elements which move close to each other. In Pol II, POLR2F/RPB6 is part of the clamp element and along with parts of RPB1 and RPB2 constructs a compartment to which the RPB4-RPB7 subcomplex attaches.

Vascular endothelial growth factoris an important signaling proteininvolved in both vasculogenesisand angiogenesis. As its name implies, VEGF activity has been mostly studied on cells of the vascular endothelium, although it does have effects on a number of other cell types (e.g. stimulation monocyte/macrophagemigration, neurons, cancer cells, kidney epithelial cells ).VEGF mediates increased vascular permeability, induces angiogenesis, vasculogenesis and endothelial cell growth, promotes cell migration, and inhibits apoptosis. In vitro, VEGF has been shown to stimulate endothelial cell mitogenesisand cell migration. VEGF is also a vasodilator and increases microvascular permeability and was originally referred to as vascular permeability factor.
Elevated levels of this protein is linked to POEMS syndrome, also known as Crow-Fukase syndrome. Mutations in this gene have been associated with proliferative and nonproliferative diabetic retinopathy.

The IL-6 receptor complex is composed of two membrane glycoproteins: the low affinity receptor and the signaltransducing component. The soluble form of IL6R is found in the urine of healthy adult humans and the serum of HIV positive individuals, as well as in the cell culture supernatants of stimulated PBMC’s. This soluble form of IL6R results from either proteolytic cleavage from the membrane, or an isoform derived splice variant.

The somatomedins, or insulin-like growth factors (IGFs), comprise a family of peptides that play important roles in mammalian growth and development. IGF1 mediates many of the growth-promoting effects of growth hormone (GH; MIM 139250). Early studies showed that growth hormone did not directly stimulate the incorporation of sulfate into cartilage, but rather acted through a serum factor, termed 'sulfation factor,' which later became known as 'somatomedin' (Daughaday et al., 1972). Three main somatomedins have been characterized: somatomedin C (IGF1), somatomedin A (IGF2; MIM 147470), and somatomedin B (MIM 193190) (Rotwein, 1986; Rosenfeld, 2003).

Killer-cell immunoglobulin-like receptors (KIRs), are a family of cell surface glycoproteins found on Natural Killer (NK) Cells, which are important cells of the immune system. They control the killing function of these cells by interacting with MHC class I molecules, which are expressed on all cell types. This interaction allows them to identify virally infected cells or tumor cells that have a distinctive low level of Class I MHC on their surface. The majority of KIRs are inhibitory, which means that their recognition of MHC suppresses the cytotoxic activity of their NK cell. Only a limited number of KIRs have the capacity to activate cells.
The KIR genes are found in a cluster on chromosome 19q13.4 within the 1 Mb leukocyte receptor complex (LRC). KIR molecules are extremely polymorphic, meaning their gene sequences differ significantly between individuals, so that different individuals have different arrays/repertoires of KIR genes.
The KIR proteins are categorized by the number of extracellular immunoglobulin domains (2D or 3D) and by whether they have a long (L) or short (S) cytoplasmic domain. KIR proteins with the long cytoplasmic domain transduce inhibitory signals upon ligand binding via an immune tyrosine-based inhibitory motif (ITIM). Whereas KIR proteins with the short cytoplasmic domain lack the ITIM motif and instead associate with the TYRO protein tyrosine kinase binding protein to transduce activating signals.
KIR2DL1 is an inhibitory Killer Cell Ig-like Receptor (KIR, previously called p58 KIR, p58.1, cl-42, NKAT1, or KIR-K6), which recognizes class I MHC molecules (HLA-Cw2, -Cw4, -Cw5, and Cw6). The extracellular domain of KIR2DL1 was over expressed as insoluble protein aggregates (inclusion bodies).

CFI cleaves and inactivates C3b and C4b. CFI is inactive without a cofactor such as the soluble factor H and C4b binding protein. CFI cleaves the alpha-peptide chain of C3b and C4b when these binds1 of the cofactors. This cleavage inactivates all of the complement activating functions of these proteins producing iC3b and iC4b.CFI cleaves the alpha chain of C3b twice and this releases a small fragment called C3f. CFI can cleave iC3b releasing C3c from C3dg in the presence of CR1.C4b is cleaved rapidly at 2 sites separating C4c from C4d.

Killer-cell immunoglobulin-like receptors (KIRs), are a family of cell surface glycoproteins found on Natural Killer (NK) Cells, which are important cells of the immune system. They control the killing function of these cells by interacting with MHC class I molecules, which are expressed on all cell types. This interaction allows them to identify virally infected cells or tumor cells that have a distinctive low level of Class I MHC on their surface. The majority of KIRs are inhibitory, which means that their recognition of MHC suppresses the cytotoxic activity of their NK cell. Only a limited number of KIRs have the capacity to activate cells.
The KIR genes are found in a cluster on chromosome 19q13.4 within the 1 Mb leukocyte receptor complex (LRC). KIR molecules are extremely polymorphic, meaning their gene sequences differ significantly between individuals, so that different individuals have different arrays/repertoires of KIR genes.
The KIR proteins are categorized by the number of extracellular immunoglobulin domains (2D or 3D) and by whether they have a long (L) or short (S) cytoplasmic domain. KIR proteins with the long cytoplasmic domain transduce inhibitory signals upon ligand binding via an immune tyrosine-based inhibitory motif (ITIM). Whereas KIR proteins with the short cytoplasmic domain lack the ITIM motif and instead associate with the TYRO protein tyrosine kinase binding protein to transduce activating signals.
The three Ig-domain from of inhibitory killer cell Ig-like receptor 1(KIR3DL1, NKB1, nkat3, p70KIR) is a NK cell receptor for polymorphic HLA-B determinant. KIR3DLl recognizes the Bw4 determinant defined by sequence motifs at positions 77-83 of the HLA-B heavy chain. The cytoplasmic tail of KIR, which contains two immunoreceptor tyrosine-based inhibition motifs (ITIMs), mediates inhibitory signal transduction that prevents killer cell-mediated cytotoxicity. A His-tag fusion protein of KIR3DL1 cytoplasmic tail (361-444aa) was overexpressed as insoluble protein aggregates (inclusion bodies).

IRF1, IFN regulatory factor 1, is a member of the IFN regulatory transcription factor (IRF) family which regulates gene expression critical to immune response, hematopoiesis and proliferation. IRF-1 is a transcriptional activator for IFN-A, IFN-B, and IFN-G stimulated genes. IRF1 is also a tumor suppressor transcription factor inducing apoptosis of tumorigenic cell lines.

Midkine (MK) is the product of a retinoic acid responsive gene. It contains 121 amino acid residues including 10 conserved cysteine residues, all of which appear to be disulphide linked.
Midkine is expressed during embryogenesis, showing an expression pattern that suggests functions in neurogenesis, cell migration, secondary organogenetic induction, and mesoderm-epithelial interaction.
The widespread downregulation of MK in the adult human is reverted in a number of cancers, in which polypeptides are able to act as both transforming growth factors and promoters of angiogenesis.
Midkine (MK), induces chemotaxis of human neutrophils and was found to trigger mobilization of intracellular calcium of these cells.
Midkine induces histamine release from rat peritoneal mast cells with a rapid response in a dose dependent manner.
Midkine is also a potent stimulator of collagen and glycosaminoglycan synthesis.

Ubiquitously-expressed transcript (UXT) is a member of the UXT family. UXT serves as a cofactor which modulates androgen receptor-dependent transcription, and also has a crucial role in tumor necrosis factor-induced apoptosis. UXT gene expression has a role in tumorigenesis. UXT is ubiquitous expressed: it is expressed in prostate epithelial cells, overexpressed in a number of tumor tissues. The highest levels are found in the heart, skeletal muscle, pancreas, kidney, liver, adrenal gland, peripheral blood leukocytes, lymph node, prostate, and thyroid and the lowest levels in bladder and uterus.