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Cystatins are a superfamily of cysteine proteinase inhibitors found in both plants and animals. They comprise a group of proteinase inhibitors, widely distributed in tissues and body fluids, and form tight complexes with cysteine proteases such as cathepsin B, H, L and S. Cystatin C, a secreted molecule of this family, is of interest from biochemical, medicine and evolutionary points of view. Cystatin C, with molecular weight of 13260 Da, is composed of 120 amino acids, lacks carbohydrate and has two disulfide bridges located near the carboxyl terminus. Cystatin C is increased in patients with malignant diseases, and is related to the insufficiency of renal function and appears to be a better marker than creatinine. On the other hand, low levels of cystatin C involve cause the breakdown of the elastic laminae and, subsequently, the atherosclerosis and abdominal aortic aneurysm.

Cystatin 7 (CST7) is a glycosylated cysteine protease inhibitor with a putative role in immune regulation through inhibition of a unique target in the hematopoietic system. Cystatin-7 is comprised of multiple cystatin-like sequences. The superfamily is comprised of 3 inhibitory families: the type 1 cystatins (stefins), type 2 cystatins and the kininogens. Some members are active cysteine protease inhibitors, while others have lost or possibly never had this inhibitory activity. Type 2 cystatin proteins are a class of cysteine proteinase inhibitors found in various human fluids and secretions. CST7 protein expression has been observed in numerous human cancer cell lines established from malignant tumors.

Intrinsic Factor is a member of the cobalamin transport protein family. It encodes a glycoprotein secreted by parietal cells of the gastric mucosa and is required for adequate absorption of vitamin B12 in the terminal ileum. Vitamin B12 is essential for erythrocyte maturation and mutations in the Intrinsic Factor may lead to congenital pernicious anemia. Upon entry into the stomach, vitamin B12 binds to one of two B12 binding proteins present in the gastric fluid. In the less acidic environment of the small intestine, these proteins dissociate from the vitamin, allowing it to bind to intrinsic factor and enter the portal circulation through a receptor in the ileal mucosa specific for the B12-intrinsic factor complex.

Nogginwhich is 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 play and important role in creating morphogenic gradients. Noggin appears to have pleiotropic effect, both early in development as well as in later stages. Noggin 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. There are several dominant human NOG mutations in unrelated families with proximal symphalangism (SYM1) and multiple synostoses syndrome (SYNS1). 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.

IFN-gamma produced by lymphocytes activated by specific antigens or mitogens.
IFN-gamma, in addition to having antiviral activity, has important immunoregulatory functions, it is a potent activator of macrophages, and has antiproliferative effects on transformed cells and it can potentiate the antiviral and antitumor effects of the type I interferons.

Sclerostin (SOST) is a secreted glycoprotein with a C-terminal cysteine knot-like (CTCK) domain and sequence similarity to the DAN (differential screening-selected gene aberrative in neuroblastoma) family of bone morphogenetic protein antagonists. Sclerostin functions as a negative regulator of bone growth, by inhibiting bone formation. SOST is expressed mainly in the bone, cartilage, kidney, liver, bone marrow and primary osteoblasts differentiated for 21 days. SOST gene defects cause sclerosteosis and bone dysplasia.

Oligonucleotide Binding Fold Containing 1 (OBFC1) is a part of the CST complex, a complex which binds to single-stranded DNA and is essential to defend telomeres from DNA degradation. The CST complex binds single-stranded DNA with high affinity in a sequence-independent way, whereas isolated subunits bind DNA with low affinity by themselves. The role of the CST complex is less specific in DNA metabolism at non-telomeric sites.

Borrelia belongs to a genus of bacteria of the spirochete phylum. Borrelia causes borreliosis, which is a zoonotic, vector-borne disease transmitted mainly by ticks and some by lice, depending on the species. Of the 36 known species of Borrelia, 12 are distinguished to cause Lyme disease or borreliosis and are transmitted by ticks. The main Borrelia species causing Lyme disease are Borrelia burgdorferi, Borrelia afzelii, and Borrelia garinii. The Borrelia genus members have a linear chromosome which is about 900 kbp in length as well as an excess of both linear and circular plasmids in the 5-220 kbp size range. The plasmids are atypical, as compared to most bacterial plasmids, since they contain many paralogous sequences, a large number of pseudogenes and, in some cases, essential genes. Moreover, a number of the plasmids have features suggesting that they are prophages.

Adipocyte fatty acid binding protein FABP4 is a 15 kDa member of the intracellular fatty acid binding protein (FABP) family, which is known for the ability to bind fatty acids and related compounds (bile acids or retinoids) in an internal cavity. FABP4 is expressed in a differentiation-dependent fashion in adipocytes and is a critical gene in the regulation of the biological function of these cells.
In mice, targeted mutations in FABP4 provide significant protection from hyperinsulinemia and insulin resistance in the context of both dietary and genetic obesity. Adipocytes obtained from FABP4-deficient mice also have reduced efficiency of ipolysis in vitro and in vivo, and these mice exhibited moderately improved systemic dyslipidemia. Recent studies also demonstrated FABP4 expression in macrophages upon differentiation and activation. In these cells, FABP4 modulates inflammatory responses and cholesterol ester accumulation, and total or macrophage-specific FABP4 deficiency confers dramatic protection against atherosclerosis in the apoE-/- mice. These results indicate a central role for FABP4 in the development of major components of the metabolic syndrome through its distinct actions in adipocytes and macrophages.

PFN2 is a ubiquitous actin monomer-binding protein which is part of the profilin family. PFN2 regulates actin polymerization in response to extra cellular signals. PFN2 binds to actin and affects the structure of the cytoskeleton. At high concentrations, profilin prevents the polymerization of actin, while it increases it at low concentrations. PFN2 binds to PIP2, it inhibits the formation of IP3 and DG.

Four and a half LIM domains 3 (FHL3) belongs to a family of proteins containing a four-and-a-half LIM domain, which is a highly conserved double zinc finger motif. FHL3 has been shown to interact with the cancer developmental regulators SMAD2, SMAD3, and SMAD4, the skeletal muscle myogenesis protein MyoD, and the high-affinity IgE beta chain regulator MZF-1. FHL3 is involved in tumor suppression, repression of MyoD expression, and repression of IgE receptor expression. Two transcript variants encoding different isoforms have been found for this gene.

FGF-1 Intracellular-Binding Protein (FIBP) which is a member of Fibroblast growth factors (FGFs) binds to internalized FGF-1 and is thought to be involved in mitogenic function of FGF-1. FGF activity effects development, adult tissue homeostasis, angiogenesis and cancer progression. FIBP localizes to the nucleus and is greatly expressed in heart, skeletal muscle and pancreas and at lower levels in brain, placenta, liver and kidney.

Pro-opiomelanocortin preproprotein (POMC) is a polypeptide hormone precursor which experiences extensive, tissue-specific, post-translational processing via cleavage by subtilisin-like enzymes known as prohormone convertases. POMC regulates the corticosteroid production in the adrenal cortex. Furthermore, POMC is cleaved into ten hormone chains named NPP, g-MSH, ACTH, a-MSH, CLIP, Lipotropin b, Lipotropin g, b-MSH,b endorphin and Met-enkephalin. POMC gene defects are the cause of POMC deficiency, which is characterized by red hair and adrenal insufficiency.

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.

UPRT is a uracil phosphoribosyltransferase, that catalyzes the alteration of uracil and 5-phosphoribosyl-1-R-diphosphate to uridine monophosphate (UMP). This reaction is a significant part of nucleotide metabolism, specifically the pyrimidine salvage pathway. UPRT is restricted to the nucleus and cytoplasm and is a possible target for rational design of drugs to cure cancer and parasitic infections.

RAP2A belongs to the RAS oncogene family and a Ras-like small G protein. The RAP2A protein shares 60% identity with Rap1A and exhibits a carboxy-terminal CAAX motif and 2 upstream cysteines similar to those of the H-Ras, K-Ras and N-Ras proteins. In contrast with Rap1A and Rap1B, overexpression of RAP2A doesn’t obstruct the Ras signaling pathway.

RBM8A belongs to the EJC (The exon junction complex) which is involved in mRNA export, cytoplasmic localization and nonsense mediated mRNA decay. RBM8A is able to communicate to the cytoplasm the processing history of the mRNA, including the position of the removed introns. Even though RBM8A shuttles to the cytoplasm, it is mostly detected in the nucleus and is colocalized with oskar mRNA at the posterior pole of the cell.

Protein Tyrosine Phosphatase Receptor Type N (PTPRN) is a catalytically inactive protein and a major target of autoimmune response in diabetes mellitus. The long C-terminal intracellular tail covers the majority of autoantibody epitopes. PTPRN is expressed in neural, neuroendocrine and pancreatic islet cells.

Actin Beta (ACTB) is one of 6 different actin isoforms which have been identified in humans. ACTB is one of the 2 nonmuscle cytoskeletal actins. Actins are highly conserved proteins which are involved in cell motility, structure and integrity. Alpha actins are a key component of the contractile apparatus.

BID accession number NP_001187 is a pro-apoptotic Bcl-2 protein having only the BH3 domain. In reaction to apoptotic signaling, BID interacts with another Bcl-2 family of cell death regulators, called Bax, they form a heterodimer resulting to the insertion of Bax into the outer mitochondrial membrane. Bax induces the opening of the mitochondrial voltage-dependent anion channel which leads to the release of cytochrome c and other pro-apoptotic factors from the mitochondria resulting in activation of caspases. BID is a mediator of mitochondrial damage induced by caspase-8 (CASP8). CASP8 cleaves BID, and the COOH-terminal part translocates to mitochondria where it triggers cytochrome c release. The major proteolytic product p15 BID releasea cytochrome c. Isoform 1, Isoform 2 and Isoform 4 induce ice-like proteases and apoptosis while Isoform 3 does not induce apoptosis.

C1QBP binds to the globular "heads" of c1q thus inhibiting c1 activation. C1QBP interacts with a wide range of ligands and is implicated in cell signaling. C1QBP associates with C1r and C1s in order to yield the first component of the serum complement system. C1QBP protein has been identified as the p32 subunit of pre-mRNA splicing factor SF2, as well as a hyaluronic acid-binding protein.
C1QBP is a new marker of tumor cells and tumor-associated macrophages/myeloid cells in hypoxic/metabolically deprived areas of tumors.
Mitochondrial C1QBP is a critical mediator of p14ARF-induced apoptosis.
C1QBP functions as a chemotactic factor for immature dendritic cells, and migration is mediated through ligation of both C1QBP and cC1qR/CR.
C1QBP overexpression successfully blocks mRNA accumulation from the adenovirus major late transcription unit (MLTU) and stimulates RNA polymerase II carboxy-terminal domain phosphorylation in virus-infected cells.
C1QBP binds with Hepacivirus core protein on CD8+ and CD4+ positive t-cells and inactivates lck and akt.

Interleukin-8 (IL-8) is a chemokine produced by macrophages and other cell types such as epithelial cells. It is also synthesized by endothelial cells, which store IL-8 in their storage vesicles, the Weibel-Palade bodies.
When first encountering an antigen, the primary cells to encounter it are the macrophages who phagocytosethe particle. Upon processing, they release chemokinesto signal other immune cells to come in to the site of inflammation. IL-8 is one such chemokine. It serves as a chemical signal that attracts neutrophilsat the site of inflammation, and therefore is also known as Neutrophil Chemotactic Factor.

The protein encoded by this gene is a cytokine that regulates T and natural killer cell activation and proliferation. This cytokine and interleukine 2 share many biological activities. They are found to bind common hematopoietin receptor subunits, and may compete for the same receptor, and thus negatively regulate each other's activity. The number of CD8+ memory cells is shown to be controlled by a balance between this cytokine and IL2. This cytokine induces the activation of JAK kinases, as well as the phosphorylation and activation of transcription activators STAT3, STAT5, and STAT6. Studies of the mouse counterpart suggested that this cytokine may increase the expression of apoptosis inhibitor BCL2L1/BCL-x(L), possibly through the transcription activation activity of STAT6, and thus prevent apoptosis. Two alternatively spliced transcript variants of this gene encoding the same protein have been reported.

Interleukin-3 is a pleiotropic cytokine produced primarily by activated T cells.
IL-3 is thought to function via specific cell surface receptors to stimulate the proliferation, differentiation and survival of haematopoietic cell lines. IL-3 has also been shown to affect the functional activity of a variety of other cell types including mast cells, eosinophils, megakaryocytes and basophils.