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Agouti-related protein is an endogenous antagonist of hypothalamic alpha-melanocortin receptors MC3R and MC4R with potent orexigenic activity. Although a complete deletion of the AGRP gene does not produce any significant metabolic phenotypes, reduction in AGRP expression by RNA interference is associated with increased metabolic rate along with reduced weight gain. In hypothalamus, it is produced by neurons in the medial portion of arcuate nucleus, which produce also the potent orexigenic peptide Neuropeptide Y (NP-Y). Another site of central AGRP production is the hypothalamic nucleus. AGRP encompasses 132 amino acid residues and its alpha-melanocortin inhibiting activity results in a 34 amino acid cystine knot domain within the C-terminal (87-132) portion of the protein. Both AGRP and NP-Y expression was shown to be suppressed by leptin. Central administration of AGRP induces hyperphagia and increased gain in body weight in rodents, but may also exert metabolic effects even when hyperphagia is prevented. In the absence of hyperphagia, intracerebralventricular administration of AGRP caused significant increases in plasma leptin and insulin concentrations (twofold and 1.5-fold, respectively) and fat pad mass.
In the periphery, AGRP mRNA was found in adrenal glands, lung, testis, ovary, skeletal muscle and adipose tissue in humans or rodents. In the adrenals, it was shown that AGRP antagonizes glucosteroid production mediated by MC4R. AGRP could then modulate locally the functions of some peripheral tissues such as adrenals.
In human and rat serum, detectable levels of AGRP-like activity were reported in the lower picogram range. The serum AGRP levels were elevated in obese humans compared to lean controls and increased with fasting in rats.

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.

ADP-ribosylation factor 5 (ARF5) is a small guanine nucleotide-binding protein which enhances the enzymatic activities of cholera toxin. ARF-dependent regulatory mechanisms include the coordination of spectrin interactions with golgi membranes and the connection of actin to the golgi via rho family-dependent G-protein localization and WASP/Arp2/3 complexes. ARF5 is involved in vesicular transport and functioning via phospholipase D activation.

NF-kappa-B inhibitor beta (NFKBIB) is a member of the NF-kappa-B inhibitor family, which inhibit NF-kappa-B by complexing with, and trapping it in the cytoplasm. Phosphorylation of serine residues on these proteins by kinases marks them for destruction via the ubiquitination pathway, thus allowing activation of the NF-kappa-B, which translocates to the nucleus to act as a transcription factor.

Ephrin-B3 (EFNB3) which belongs to the ephrin gene family is essential in brain development as well as in its maintenance. EFNB3 binds to, and induces the collapse of, commissural axons/growth cones in vitro. EFNB3 loosely binds Eph receptors located on bordering cells, leading to contact-dependent bidirectional signaling into neighboring cells. The EPH and EPH-related receptors comprise the largest subfamily of receptor protein-tyrosine kinases and are implicated in mediating developmental events, mostly in the nervous system.

Omentin is a recently recognized gene highly localized to the mental tissue (visceral adipose tissue). Omentin is present in the stromal vascular cells in the adipose tissue rather than in the adipocytes. Omentin is predominantly expressed in the visceral adipose tissue than the subcutaneous tissue, with the omentin mRNA being 150 times higher in the visceral adipose tissue. Omentin has also been detected in human blood using western blot analysis, and seems to increase insulin-stimulated glucose uptake in 3T3-L1 adipocytes in mice. Omentin seems to increase Akt phosphorylation irrespective of insulin presence. Its role in glucose metabolism and obesity remains to be described; an insulin-sensitizing action is possible.Differences in Omentin expression has been noted in adipose tissue from normals and patients with inflammatory bowel disease although its significance is unknown.

Canopy FGF Signaling Regulator 1, also known as CNPY1, is expressed in the midbrain-hindbrain (MHB) boundary in zebrafish. CNPY1, which binds FGFR1, also takes part in FGF signaling.

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.

HCV is a small 50nm, enveloped, single-stranded, positive sense RNAvirus in the family Flaviviridae.
HCV has a high rate of replication with approximately one trillion particles produced each day in an infected individual. Due to lack of proofreading by the HCV RNA polymerase, the HCV has an exceptionally high mutation rate, a factor that may help it elude the host's immune response. Hepatitis C virus is classified into six genotypes(1-6) with several subtypes within each genotype. The preponderance and distribution of HCV genotypes varies globally. Genotype is clinically important in determining potential response to interferon-based therapy and the required duration of such therapy. Genotypes 1 and 4 are less responsive to interferon-based treatment than are the other genotypes (2, 3, 5 and 6).

Interleukin-4 is a pleiotropic cytokine produced primarily by activated T lymphocytes, basophils and mast cells. Multiple immune response-modulating functions are performed by IL-4 on a variety of cell types and it has an important role in the regulator of isotype switching, induction of IgE production in B lymphocytes and differentiation of precursor T helper cells. IL-4 binds to both membrane-bound and secreted soluble IL-4 receptors.

Dendritic cell and monocyte chemokinelike protein (DMC/CXCL17/VEGF-correlated chemokine 1/VCC1), is a secreted molecule with a size and predicted 3-dimensional folding pattern similar to that of chemokines CXCL8/IL8 and CXCL14/BRAK. CXCL17 is constitutively generated by airway and intestinal epithelium. CXCL17 induces the chemotaxis of quiescent, but not LPS-activated peripheral blood monocytes and dendritic cells, and it also binds these cells specifically. The expression of CXCL17 is increased in endothelial cells when they are induced to form tubes in vitro. CXCL17, CXCL1/GRO and CXCL8/IL8 which have roles in angiogenesis, show significantly correlated expression with that of VEGF in primary lung, breast and esophageal tumors. Therefore, CXCL17 is suggested to have a role in tumor angiogenesis. The mature Rat CXCL17 shares 82%, 71% amino acid sequence identity with mouse, human CXCL17, respectively.

Dystroglycan 1 (DAG1) is a laminin binding component of the dystrophin-glycoprotein complex which provides a connection between the subsarcolemmal cytoskeleton and the extracellular matrix. The N-terminal domain of alpha-dystroglycan is secreted into the cerebrospinal fluid. The effect of DAG1 on the nervous system remains vague. The complete dystroglycan complex is expressed in a various tissues and has a role in processes such as laminin and basement membrane assembly, sarcolemmal stability, cell survival, peripheral nerve myelination, nodal structure, cell migration, and epithelial polarization. DAG1 is a candidate gene for the site of the mutation in autosomal recessive muscular dystrophies. The dramatic decrease of DAG1 in Duchenne muscular dystrophy leads to a loss of linkage between the sarcolemma and extracellular matrix, making muscle fibers more susceptible to necrosis.

Secernin 1 (SCRN1) which is a member of the peptidase C69 family, regulates exocytosis in mast cells. SCRN1 increases both the level of secretion and the sensitivity of mast cells to stimulation with calcium.

Decorin (DCN) is a small cellular or pericellular matrix proteoglycan which is closely related in structure to biglycan protein. Decorin is a secreted protein which binds to collagen and fibronectin in extracellular matrix. Decorin appears in different glycoforms, substituted with chondroitin sulfate or dermatan sulfate consistent with the original tissue. DCN contains one attached glycosaminoglycan chain. Decorin influences the rate of fibril formation. Decorin is capable of suppressing the growth of various tumor cell lines. DCN gene defects cause corneal dystrophy. The DCN gene is a candidate gene for Marfan syndrome.

Cytotoxicity Triggering Receptor 3 also known as NCR3 is a natural cytotoxicity receptor (NCR) which assists NK cells in the lysis of tumor cells. Moreover, NCR3 interacts with CD3-zeta (CD247), a T-cell receptor. A single nucleotide polymorphism in the 5' untranslated region of NCR3 has been related with mild malaria suceptibility. Three transcript variants encoding various isoforms have been found for this gene.

STMN2 is a neuronal growth-associated protein which shares a majority of its amino acid sequence with the phosphoprotein stathmin. STMN2 is involved in neuronal differentiation and in modulating membrane interaction with the cytoskeleton through neurite outgrowth. STMN2 is necessary for maintaining the anchorage-independent growth state of beta-catenin/TCF-activated hepatoma cells. SCG10 is a novel indicator of osteogenesis and osteoblast that takes part in the regulation of the adipocyte/osteoblast balance. STMN2 plays a role as an effector downstream of Rnd1 to regulate axon extensions by modulating microtubule organization.

TIGAR is a p53-inducible enzyme which catalyzes the hydrolysis of fructose-2-6 bisphosphate (F-2-6-BP) to fructose-6-phosphate and inorganic phosphate. F-2-6-BP is an influential activator of 6-phosphofructose-1 kinase (the rate limiting enzyme of glycolysis). By lowering the intracellular level of F-2-6-BP, TIGAR expression leads to increased glucose processing through the pentose phosphate pathway, the main cellular source for NADPH. Protein transduction using TAT fusion proteins represents an alternative methodology for introducing transcription factors and other intracellular proteins into primary as well as transformed cells.

Calumenin is a calcium-binding protein located in the endoplasmic reticulum (ER) and sarcoplasmic reticulum (SR) of mammalian tissues which plays a role in ER functions as protein folding and sorting. Calumenin belongs to a family of multiple EF-hand proteins (CERC) that include reticulocalbin, ERC-55, and Cab45 and the product of this gene. Calumenin binds 7 calcium ions having low affinity and takes part in such ER functions as protein folding and sorting.

Inhibitor of Growth Family Member 1, also known as ING1 is a tumor suppressor protein which is able to induce cell growth arrest and apoptosis. ING1 is a nuclear protein which physically act together with the tumor suppressor protein TP53 and is a component of the p53 signaling pathway. In addition, Reduced expression and rearrangement of ING1 have been identified in various cancers. Multiple alternatively spliced transcript variants encoding distinct isoforms have been described for ING1.

Integrins are heterodimeric proteins consist of alpha and beta subunits. There are more than 18 alpha and 8 beta subunits discovered in mammals. Integrin family members are membrane receptors that participates in cell adhesion and recognition in a variety of processes including embryogenesis, hemostasis, tissue repair, immune response and metastatic diffusion of tumor cells. ITGB1 encodes a beta subunit.

Guanine Nucleotide Binding Protein Gamma 12, also known as GNG12 belongs to the Guanine nucleotide-binding proteins (G proteins) which are involved as a modulator or transducer in a variety of transmembrane signaling systems. In addition, the beta as well as gamma chains are essential for the GTPase activity, for replacement of GDP by GTP, and also for G protein-effector interaction.

Excess adiposity is the most important risk in the development of insulin resistance and type 2 diabetes mellitus (T2DM). Adipose tissue produces several proteins (adipocytokines) such as leptin, adiponectin, resistin, tumor necrosis factor-?, and IL-6, that modulate insulin sensitivity and appear to play an important role in the pathogenesis of insulin resistance, diabetes, dyslipidemia, inflammation, and atherosclerosis. However, the mechanisms by which fat tissue induces insulin resistance and the role of adipocytokines in the pathogenesis of T2DM have not been well established. Visfatin, also known as pre-B cell colony-enhancing factor (PBEF), is a cytokine that is highly expressed in visceral fat and was originally isolated as a secreted factor that synergizes with IL-7 and stem cell factors to promote the growth of B cell precursors. Visfatin homologs have been identified in carp, invertebrate mollusks, and bacteria, as well as in vertebrates, including humans and the mouse. It has been postulated to play a role in innate immunity.
Visfatin exerts insulin-mimetic effects that are dose-dependent and quantitatively similar to those of insulin in stimulating muscle and adipocyte glucose transport, and in inhibiting hepatocyte glucose production. Intravenous injection of recombinant visfatin in mice decreased plasma glucose in a dose-dependent fashion. In keeping with its insulin-mimetic effects, visfatin was as effective as insulin in reducing hyperglycemia in insulin-deficient diabetic mice. Visfatin was also found to be bound to and activate insulin receptor, causing receptor phosphorylation and the activation of downstream signaling molecules. However, visfatin and insulin did not compete for binding to the insulin receptor, indicating that the two proteins were recognized by different regions of the receptor. Thus, visfatin might play a role in glucose homeostasis and dysregulation in biosynthesis or signal transduction, and might contribute to the pathogenesis of diabetes.

Prorelaxin H2 (RLN2) is a member of a family which is produced by the ovary, targets the mammalian reproductive system to ripen the cervix, elongate the pubic symphysis and inhibit uterine contraction. It may also have other roles in boosting sperm motility, regulating blood pressure, controlling heart rate and releasing vasopressin. RLN2 is a peptide hormone linked to several therapeutically relevant physiological effects, including regulation of collagen metabolism and multiple vascular control pathways. The active form of the RLN2 protein consists of an A chain and a B chain linked by disulfide bonds.

GDF15 is part of the TGF-Beta superfamily that is involved in regulating inflammatory and apoptotic pathways in injured tissues and throughout disease processes. GDF15 is most abundant in the liver. Its expression in liver can be considerably up-regulated in during injury of organs such as liver, kidney, heart and lung. GDF-15 promotes proliferation or growth arrest and differentiation due to differences in cellular differentiation. GDF15 prevents apoptosis in cerebellar granule neurons by activating Akt and inhibiting endogenously active ERK. GDF15 is a novel autocrine/endocrine factor that antagonizes the hypertrophic response and loss of ventricular performance.