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Von Hippel-Lindau disease is a dominant inherited syndrome characterized by the predisposition to develop various kinds of benign and malignant tumors, including clear cell renal carcinomas, pheochromocytomas and hemangioblastomas of the central nervous system and retina. VHL syndrome is caused by germline mutation in the VHL tumor suppressor, and VHL tumors are associated with loss or mutation of the remaining wild-type allele. VHL has two domains: a roughly 100-residue NH2-terminal domain rich in b sheet (b-domain) and a smaller a-helical domain (a-domain), held together by two linkers and a polar interface. VHL protein is also involved in the degradation of hypoxia-inducible factor (HIF).

Cellular Repressor of E1A-Stimulated Genes 1 (CREG1) both activates and inhibits gene expression to stimulate cellular proliferation and hinder differentiation. CREG1 antagonizes transcriptional activation and cellular transformation by E1A. CREG1 shares partial sequence similarity with E1A and binds both the general transcription factor TBP and the tumor suppressor pRb in vitro. CREG1 contributes to the transcriptional control of cell growth and differentiation.

Resistin, a product of the RSTN gene, is a peptide hormone belonging to the class of cysteine-rich secreted proteins which is termed the RELM family, and is also described as ADSF (Adipose Tissue- Specific Secretory Factor) and FIZZ3 (Found in Inflammatory Zone). Human resistin contains 108 amino acids as a prepeptide, and its hydrofobic signal peptide is cleaved before its secretion. Resistin circulates in human blood as a dimeric protein consisting of two 92 amino acid polypeptides, which are disulfide-linked via Cys26.
Resistin may be an important link between obesity and insulin resistance. Mouse resistin, specifically produced and secreted by adipocyte, acts on skeletal muscle myocytes, hepatocytes and adipocytes themselves so that it reduces their sensitivity to insulin. Steppan et al. have suggested that resistin suppresses the ability of insulin to stimulate glucose uptake. They have also suggested that resistin is present at elevated levels in blood of obese mice, and is down regulated by fasting and antidiabetic drugs. Way et al., on the other hand, have found that resistin expression is severly suppressed in obesity and is stimulated by several antidiabetic drugs.
Other studies have shown that mouse resistin increases during the differentiation of adipocytes, but it also seems to inhibit adipogenesis. In contrast, the human adipogenic differentiation is likely to be associated with a down regulation of resistin gene expression.

IFN-alpha is produced by macrophages and has antiviral activities. Interferon stimulates the production of two enzymes: protein kinase and an oligoadenylate synthetase.

C1QTNF6 is a collagen type-IV specific for basement membranes. C1QTNF6 is vital for embryonic development.

PLAUR is one of 2 activators which convert the extracellular zymogen plasminogen to plasmin, a serine protease involved in a various normal and pathological processes that require cell migration and/or tissue destruction. PLAUR protein is synthesized and released from cells as a single-chain proenzyme with narrow enzymatic activity and is converted to an active two-chain disulfide-linked active enzyme by plasmin and other specific proteinases.

Leukocyte Cell-Derived Chemotaxin 2 (LECT2) functions as a chemotactic factor to neutrophils. LECT2 stimulates the proliferation of chondrocytes and osteoblasts. LECT2 is strongly expressed in the liver and weakly in the testis. LECT2 is a secreted, 16kDa protein which serves as a chemotactic factor to neutrophils and stimulates the growth of chondrocytes and osteoblasts. LECT2 protein has a high sequence similarity to the chondromodulin repeat regions of the chicken myb-induced myeloid 1 protein. A polymorphism in the LECT2 gene is linked with rheumatoid arthritis.

Protein A is a cell wall component produced by several strains of Staphylococcus aureus. The recombinant Protein A is genetically engineered protein and holds 5 IgG-binding regions of protein A. Recombinant Protein A functions basically the same as native Protein A and is perfect for purification of polyclonal or monoclonal IgG antibodies. Protein A binds to human IgG1, IgG2 and IgG4, mouse IgG2a, IgG2b and IgG3 and rat IgG2c. Protein A also binds to total IgG from rabbit, pig, dog, cat, and guinea pig.

Macrophage Inflammatory Proteins (MIP) belong to the family of chemotactic cytokines known as chemokines. In humans, there are two major forms, MIP-1a and MIP-1b that are now officially named CCL3 and CCL4 respectively. Both are major factors produced by macrophages after they are stimulated with bacterial endotoxins. They activate human granulocytes (neutrophils, eosinophils and basophils) which can lead to acute neutrophilic inflammation. They also induce the synthesis and release of other pro-inflammatory cytokines such as interleukin 1 (IL-1), IL-6 and TNF-a from fibroblasts and macrophages. The genes for CCL3 and CCL4 are both located on human chromosome 17.

Cytotoxic T-lymphocyte-associated protein 4 or CTLA4 or CD152 is a receptor that takes part in the immune checkpoint and inhibits immune response. This protein is fundamentally found in regulatory T cells; however, it acts as an enhancer in regular T cells following its activation, this is eminent in cancers. CTLA4 bounds to CD80 or CD86 on the membrane of antigen presenting cells and downregulates transductions.

Hypoxia-inducible factor-1 (HIF-1), identified as one of the transcription factors, has been found to play an essential role in cellular and systemic oxygen homeostasis. HIF-1 is a heterodimer composed of HIF-1b subunit and one of three subunits (Hif-1a, Hif-2 (or Hif-3)). The activation of Hif-1 (is closely associated with a variety of tumors and oncogenic pathways. Hif-1 (consists of DNA binding domain (DBD domain), Dimerization domain and C-terminal regulatory domains, including two transactivation domains (TAD), an oxygen-dependent degradation (ODD) domain, and inhibitory domains. Under hypoxic conditions HIF1A activates the transcription of more than 40 genes, including, erythropoietin, glucose transporters, glycolytic enzymes, VEGF, and other genes whose protein products increase oxygen delivery or facilitate metabolic adaptation to hypoxia. HIF-1A also plays a crucial role in embryonic vascularization, tumor angiogenesis and pathophysiology of ischemic disease. It binds to core DNA sequence 5'-[AG]CGTG-3' within the hypoxia response element (HRE) of target gene promoters. Activation involves recruitment of transcriptional coactivators such as CREBPB and EP300. Its activity is improved by interaction with both, NCOA1 or NCOA2. Interaction with redox regulatory protein APEX appears to activate CTAD and potentiates activation by NCOA1 and CREBBP. The induction is under reduced oxygen tension. HIF1A is also induced by a variety of receptor-mediated factors such as growth factors, cytokines, and circulatory factors for example PDGF, EGF, FGF-2, IGF-2, TGF-1 beta, HGF, TNF alpha, IL-1 beta, angiotensin-2 and thrombin. Nevertheless, this induction is less intense than that stimulated by hypoxia.

Major Histocompatibility Complex Class I C (HLA-C) belongs to the HLA class I heavy chain paralogues. The HLA-C (class I molecule) is a heterodimer comprised of a heavy chain and a light chain (beta-2 microglobulin). The heavy chain is anchored in the membrane. Class I molecules have a key role in the immune system by presenting peptides derived from endoplasmic reticulum lumen. Class I molecules are expressed in virtually all cells.

Plasma protease C1 inhibitor (SERPING1) is a part of the serpin superfamily of serine protease inhibitors. SERPING1 plays an important role in regulating activation of both the complement and contact systems. That isdue to the fact that SERPING1 regulates the activation of complement factor C1 in addition to the activity of activated C1 by coupling with the active catalytic site at the light chains of C1r and C1s. SERPING1 insufficiency results in hereditary angioedema, which is characterized by recurrent episodes of localized angioedema of the skin, gastrointestinal mucosa or upper respiratory mucosa.

Chemokine (C-X-C motif) ligand (CXCL7) is a small cytokine belonging to the CXC chemokine family. It is a protein that is released in large amounts from platelets following their activation. It stimulates various processes including mitogenesis, synthesis of extracellular matrix, glucose metabolism and synthesis of plasminogen activator.

a-Synuclein (amino acids 1-140), an acidic neuronal protein of 140 amino acids, is extremely heat-resistant and is natively unfolded with an extended structure primarily composed of random coils. a-synuclein has been suggested to be implicated in the pathogenesis of Parkinson’s disease and related neurodegenerative disorders, and more recently, to be an important regulatory component of vesicular transport in neuronal cells. Moreover, recent studies have shown that a-synuclein has chaperone activity and that this activity is lost upon removing its C-terminal acidic tail (amino acids 96-140).

The secreted polypeptide noggin, encoded by the NOG gene, binds and inactivates members of the transforming growth factor-beta (TGF-beta) superfamily signaling proteins, such as bone morphogenetic protein-4 (BMP4). By diffusing through extracellular matrices more efficiently than members of the TGF-beta superfamily, noggin may have a principal role in creating morphogenic gradients. Noggin appears to have pleiotropic effect, both early in development as well as in later stages. It was originally isolated from Xenopus based on its ability to restore normal dorsal-ventral body axis in embryos that had been artificially ventralized by UV treatment. The results of the mouse knockout of noggin suggest that it is involved in numerous developmental processes, such as neural tube fusion and joint formation. Recently, several dominant human NOG mutations in unrelated families with proximal symphalangism (SYM1) and multiple synostoses syndrome (SYNS1) were identified; both SYM1 and SYNS1 have multiple joint fusion as their principal feature, and map to the same region (17q22) as NOG. All NOG mutations altered evolutionarily conserved amino acid residues. The amino acid sequence of human noggin is highly homologous to that of Xenopus, rat and mouse.

The somatomedins, or IGFs, comprise a family of peptides that play important roles in mammalian growth and development. IGF1 mediates many of the growth-promoting effects of GH. Early studies showed that GH 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. Three main somatomedins have been characterized: somatomedin C (IGF1), somatomedin A (IGF2), and somatomedin B.

Chemokine (C-X-C motif) ligand 5 (CXCL5) is a small cytokine belonging to the CXC chemokine family that is also known as epithelial-derived neutrophil-activating peptide 78 (ENA-78). It is produced following stimulation of cells with the inflammatory cytokines interleukin-1 or tumor necrosis factor-alpha. Expression of CXCL5 has also been observed in eosinophils. This chemokine stimulates the chemotaxis of neutrophils possesses angiogenic properties. It elicits these effects by interacting with the cell surface chemokine receptor CXCR2. The gene for CXCL5 is encoded on four exons and is located on human chromosome 4 amongst several other CXC chemokine genes. CXCL5 has been implicated in connective tissue remodelling.

Profilin1 (PFN1) is a ubiquitous actin monomer-binding protein which is a member of the profilin family. PFN1 significantly boosts skin wound healing in-vitro and in-vivo which may be mediated by purinergic receptors. PFN1 is also active in endothelial cell migration and vessel sprouting. PFN1 is thought to control actin polymerization in response to extracellular signals. PFN1 binds to actin and affects the formation of the cytoskeleton. In addition, PFN1 has an important role in the regulation of epithelial cell-cell adhesion. At high concentrations, profilin averts the polymerization of actin, while at low concentrations it enhances the polymerization. PFN1 gene deletion is linked to Miller-Dieker syndrome.

Capping Protein (Actin Filament) Muscle Z-Line, Alpha 2 also known as CAPZA2 belongs the F-actin capping protein alpha subunit family. It is the alpha subunit of the barbed-end actin binding protein Cap Z. By capping the barbed end of actin filaments, Cap Z regulates the growth of the actin filaments at the barbed end. Among the diseases associated with CAPZA2 are endocarditis, and cervicitis.

Tripartite Motif Containing 28 (TRIM28) which is a member of the tripartite motif family includes 3 zinc-binding domains, a RING, a B-box type 1 and a B-box type 2, and a coiled-coil region. TRIM28 mediates transcriptional control by interaction with the Kruppel-associated box repression domain found in many transcription factors. TRIM28 is restricted to the nucleus and connected with particular chromatin regions.

Chromgranin-A is part of the neuroendocrine secretory protein family. CHGA is located in secretory vesicles of neurons and endocrine cells. Chromgranin-A is a precursor to three biologically active peptides; vasostatin, pancreastatin, and parastatin. These peptides act as autocrine or paracrine negative modulators of the neuroendocrine system. Other peptides, including chromostatin, beta-granin, WE-14 and GE-25, are also derived from the full-length protein. Chromgranin-A has numerous biological activities on some tissues and organs and exerts a large spectrum of homeostatic actions, including antifungal and antimicrobial effect, modulation of cell adhesion, and inhibition of parathyroid hormone secretion.

Chemokine (C-X-C motif) ligand 1 (CXCL1) is a small cytokine belonging to the CXC chemokine family that was previously called GRO1 oncogene, Neutrophil-activating protein 3 (NAP-3) and melanoma growth stimulating activity, alpha (MSGA-a). It is secreted by human melanoma cells, has mitogenic properties and is implicated in melanoma pathogenesis. CXCL1 is expressed by macrophages, neutrophils and epithelial cells, and has neutrophil chemoattractant activity. CXCL1 plays a role in spinal cord development by inhibiting the migration of oligodendrocyte precursors and is involved in the processes of angiogenesis, inflammation, wound healing, and tumorigenesis. This chemokine elicits its effects by signaling through the chemokine receptor CXCR2. The gene for CXCL1 is located on human chromosome 4 amongst genes for other CXC chemokines.

Recombinant Human X-Ray Repair Cross Complementing Protein 3, also referred to XRCC3, is a member of RecA family and RAD51 subfamily. The protein takes partin homologous recombination to maintain chromosome stability and repair DNA damage. XRCC3functionally complements Chinese hamster irs1SF, a repair-deficient mutant that shows hypersensitivity to a number of different DNA-damaging agents & chromosomally unstable.