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High-mobility group box 1 protein (HMGB1), previously known as HMG-1 or amphoterin, is a member of the high mobility group box family of non-histone chromosomal proteins. Human HMGB1 is expressed as a 30 kDa, 215 amino acid (aa) single chain polypeptide containing three domains: two N-terminal globular, 70 aa positively charged DNA-binding domains (HMG boxes A and B), and a negatively charged 30 aa C-terminal region that contains only Asp and Glu.4, 5 Residues 27 - 43 and 178 - 184 contain a NLS. Posttranslational modifications of the molecule have been reported, with acetylation occurring on as many as 17 lysine residues. HMGB1 is expressed at high levels in almost all cells. It was originally discovered as a nuclear protein that could bend DNA. Such bending stabilizes nucleosome formation and regulates the expression of select genes upon recruitment by DNA binding proteins.

NCR2 (NKp44) belongs to the natural cytotoxicity receptor (NCR) family which is expressed on activated human NK cells. NKp44 exhibits a single extracellular Ig-like V domain and a transmembrane portion containing the charged residue (Lysine), possibly involved in the association with KARAP/DAP12 molecules. The gene coding for NKp44 maps on human chromosome 6p21.1.

The scaffolding protein encoded by the CAV1 gene is the key component of the caveolae plasma membranes found in most cell types. Cholesterol is vital for caveolae formation and maintenance, and caveolae structure is highly sensitive to cholesterol depletion or treatment with cholesterol binding drugs. CAV1 can tightly and specifically bind free cholesterol and artificial cholesterol containing vesicles. Caveolin 1 links integrin subunits to the tyrosine kinase FYN, which is an initiating step in coupling integrins to the Ras-ERK pathway and promoting cell cycle progression. CAV1 is a tumor suppressor gene candidate and a negative regulator of the Ras-p42/44 mitogen-activated kinase. Caveolin 1 and caveolin 2 are positioned next to each other on chromosome 7 and express co-localizing proteins which form a stable hetero-oligomeric complex cascade. Mutations in the CAV1 gene are linked to Berardinelli-Seip congenital lipodystrophy.

KLRD1, also known as Killer Cell Lectin Like Receptor D1, is expressed on the surface of natural killer cells in the innate immune system. KLRD1 functions as a receptor for the recognition of MHC class I HLA-E molecules by NK cells and some cytotoxic T-cells. KLRD1 can create disulfide-bonded heterodimer with NKG2 family members. CD94 & NKG2 complex interacts with (HLA)-E, Human Leukocyte Antigen on target cells on the surface of natural killer cells.

Cytokeratin 23 (KRT23) is a 422 amino acid intermediate filament protein. The human KRT23 gene is found on chromosome 17q21.2. Type I cytokeratins consist of acidic proteins which are organized in pairs of heterotypic keratin chains. The cytokeratin proteins have an essential role in differentiation, plus tissue specialization and function, and epithelial cells structure maintenance. Cytokeratins are portrayed to be differentiation markers in a number of epithelial cancers.

Glia Maturation Factor-Beta (GMF-Beta) is a 17 kDa protein nerve gorwth factor identified as a growth and differentiation factor in the vertebrate brain.

Glia Maturation Factor-Beta stimulates differentiation of normal neurons as well as glial cells. GMFB inhibits the proliferation of the N-18 neuroblastoma line and the C6 glioma line while promoting their phenotypic expression.
GMF-beta inhances the phenotypic expression of glia & neurons thus inhibits the proliferation of their respective tumors when added to cell culture. Although astrocytes produce GMF-b and stores it inside the cells, they don’t secrete the GMF-B into the cultured medium. Cell- surface GMFb acts on the target cells at close range when cells are in direct contact. GMF-Beta is produced by thymic epithelial cells and plays an important role in T cell development in favor of CD4+ T cells.
GMF-Beta is a brain-specific protein which belongs to the actin-binding proteins (ADF) family. GMF-beta appears to play a role in the differentiation, maintenance, and regeneration of the nervous system. It also supports the progression of certain auto-immune diseases, possibly through its ability to induce the production and secretion of various pro-inflammatory cytokines.

ANGPTL3 and ANGPTL4 are angiopoietin-like proteins secreted and expressed mainly by the liver, their role being the regulation of triglyceride metabolism by inhibiting the lipolysis of triglyceride-rich lipoproteins. During different nutritional states (feeding/fasting) the levels of the circulating triglycerides are regulated by Angptl3 and Angptl4 through differential inhibition of Lipoprotein lipase (LPL) as shown by the experimental data. The molecular structure of ANGPTL3 is similar to that of the angiopoietins (vascular endothelial growth factors). Deletion mutants of human Angiopoietin 5 were used in order to demonstrate that the N-terminal domain (fragment 17-207) and not the C-terminal fibrinogen-like domain (fragment 207-460) increased the plasma triglyceride levels in mice.

Cytokeratin 17 also known as KRT17 is a type I cytokeratin. KRT17 is found in nail beds, hair follicles, sebaceous glands, and other epidermal appendages. Mutations in KRT17 lead to Jackson-Lawler type pachyonychia congenita and steatocystoma multiplex. KRT17 takes part in the formation and maintenance of a variety of skin appendages, particularly in determining shape and orientation of hair. KRT17 also modulates the function of TNF-alpha in the precise context of hair cycling. Moreover, KRT17 regulates protein synthesis and epithelial cell growth all through binding to the adapter protein SFN and by stimulating Akt/mTOR pathway.

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.

Vascular endothelial growth factor is an important signaling protein involved in both vasculogenesis and 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 are linked to POEMS syndrome, also known as Crow-Fukase syndrome. Mutations in this gene have been associated with proliferative and nonproliferative diabetic retinopathy.

Tumor necrosis factor is a cytokine involved in systemic inflammation and is a member of a group of cytokines that all stimulate the acute phase reaction. TNF is mainly secreted by macrophages.
TNF causes apoptotic cell death, cellular proliferation, differentiation, inflammation, tumorigenesisand viral replication, TNF is also involved in lipid metabolism, and coagulation. TNF's primary role is in the regulation of immune cells.
Dysregulation and, in particular, overproduction of TNF have been implicated in a variety of human diseases- autoimmune diseases, insulin resistance, and cancer.

CB1 cannabinoid receptor-interacting protein 1 (CNRIP1) is a 164 amino acid protein and G-protein coupled receptor which is a member of the CNRIP family. The CNRIP1 interacts with the C-terminal tail of cannabinoid receptor 1. CNRIP1 is expressed in the brain tissue and, at low levels, in the testis. CNRIP1 is involved in appetite, synaptic plasticity, neuroprotection and analgesia.

R-Spondin-1 (Rspo1) is a part of the Rspondin family. Rspo1 plays a role as an activator of the canonical Wnt signaling pathway by acting as a ligand for LGR4-6 receptors. Rspo1 induces the onset of crypt cell proliferation and increases intestinal epithelial healing effect. Rspo1 is negatively regulating the TGF-beta pathway.

Tumor necrosis factor is a cytokine involved in systemic inflammation and is a member of a group of cytokines that all stimulate the acute phase reaction. TNF is mainly secreted by macrophages.
TNF causes apoptotic cell death, cellular proliferation, differentiation, inflammation, tumorigenesisand viral replication, TNF is also involved in lipid metabolism, and coagulation. TNF's primary role is in the regulation of immune cells.
Dysregulation and, in particular, overproduction of TNF have been implicated in a variety of human diseases- autoimmune diseases, insulin resistance, and cancer.

Uromodulin is the most abundant protein in normal urine. Its secretion in urine follows proteolytic cleavage of the ectodomain of its glycosyl phosphatidylinosital-anchored counterpart that is situated on the luminal cell surface of the loop of Henle. Uromodulin plays a role as a constitutive inhibitor of calcium crystallization in renal fluids. Secretion of uromodulin in urine provides protection against urinary tract infections caused by uropathogenic bacteria. Defects in Uromodulin expression are associated with the autosomal dominant renal disorders medullary cystic kidney disease-2 (MCKD2) and familial juvenile hyperuricemic nephropathy (FJHN). These disorders are characterized by juvenile onset of hyperuricemia, gout, and progressive renal failure. While several transcript variants may exist for this gene, the full-length natures of only two have been described to date. UMOD is involved in regulating the circulating activity of cytokines as it binds to il-1, il-2 and tnf with high affinity.

LRPAP1 is a member of the alpha-2-MRAP family. LRPAP1 cooperates with LRP1/alpha-2-macroglobulin receptor and glycoprotein 330. LRPAP1, located on the cell surface, creates a complex with the alpha 2 macroglobulin receptor light and heavy chains and has part in the pathogenesis of membrane glomerular nephritis.

The cytokine Macrophage migration inhibitory factor (MIF) has been identified to be secreted by the pituitary gland and the monocyte/macrophage and to play an important role in endotoxic shock. MIF has the unique property of being released from macrophages and T cells in response to physiological concentrations of glucocorticoids. The secretion of MIF is tightly regulated and decreases at high, anti-inflammatory steroid concentration.

ISG15 ubiquitin-like Modifier is conjugated to the intracellular target proteins after IFN-alpha or IFN-beta stimulation. ISG15 enzymatic pathway is partially distinct from that of ubiquitin, differing in substrate specificity and interaction with ligating enzymes. ISG15 conjugation pathway uses a dedicated E1 enzyme, but seems to converge with the ub conjugation pathway at the level of a specific E2 enzyme. ISG15 protein targets include STAT1, SERPINA 3G/SPI2A, JAK1, MAPK3/ERK1, PLCG1, EIF2AK2/PKR, MX1/MXA, and RIG-1. Deconjugated by USP18/UBP43 shows specific chemotactic activity towards neutrophils and activates them to induce release of eosinophil chemotactic factors. ISG15 serves as a trans-acting binding factor directing the association of ligated target proteins to intermediate filaments. ISG15 plays a role in autocrine, paracrine and endocrine mechanisms, as in cell-to-cell signaling, possibly partly by inducing ifn-gamma secretion by monocytes and macrophages. ISG15 displays antiviral activity during viral infections. ISG15 in response to IFN-TAU secreted by the conceptus, ligates to and regulate proteins involved in the release of prostaglandin F2-alpha and thus prevent lysis of the corpus luteum and maintain the pregnancy. ISG15 shares several common properties with other ubiquitin-like molecules, but its activity is strongly regulated by precise signaling pathways that have a role in innate immunity.

Lanreotide is a peptide inhibitor of a number of endocrine, neuroendocrine, exocrine and paracrine functions. It shows good affinity for peripheral somatostatin receptors (anterior pituitary and pancreatic). In contrast, its affinity for central receptors is much lower. This profile confers a good specificity of action at the level of growth hormone and digestive hormone secretion. Lanreotide shows a much longer duration of action than natural somatostatin. In addition, its marked selectivity for the secretion of growth hormone, compared to that of insulin, makes it a suitable candidate for the treatment of acromegaly. By inhibiting the synthesis of thyroid stimulating hormone (TSH), lanreotide also normalised thyroid function of patients with thyrotrophin secreting adenomas in 50% (8/16) of the per-protocol population treated for 6 months. There was no significant reduction in the size of the adenoma. Furthermore, the inhibitory action of lanreotide on intestinal exocrine secretion, d

NECTIN3, also known as Nectin Cell Adhesion Molecule 3, is part of the nectin family. NECTIN3 is intended to initiate cell-cell adhesion to stimulate cell attachment and to allow subsequent formation of JAM-and cadherin-based intercellular junctions. NECTIN3 induces endocytosis-mediated down-regulation of PVR from the cell surface, which results in reduction of cell movement & proliferation. Following Nectin-3 activity adds strength to the junction through trans-interaction with various molecules.

A natural cytotoxicity receptor (NCR) NKp46 has been shown to represent a novel NK cell-specific molecule involved in human NK cell activation. The natural cytotoxicity receptors (NCRs) are a recently characterized family of Ig-like activation receptors that appear to be major triggering receptors in tumor cell recognition. The three known NCRs include NKp46 and NKp30, which are expressed on circulating NKcells, and NKp44, which is expressed only on activating NK cells. NKp46 has been implicated in NK cell-mediated lysis of several autologous tumor cells, pathogen-infected cell lines and mononuclear phagocytes infected with an intracellular bacterium. The Lysis of tumor cells by NK-cells involves recognition by NKp46 of heparan sulfate moieties of membrane heparan sulfate proteoglycans. Furthermore, NKp46 is a surface receptor involved in NK-cell cell death by apoptosis. NKp46 has two extracellular Ig-like domains followed by a ~40 residue stalk region, a type I transmembrane domain, and a short cytoplasmic tail. The extracellular Ig-like domain of NKp46 (22-255aa) is purified by FPLC gel-filtration chromatography, after refolding of the isolated inclusion bodies in a redox buffer. In addition, engagement of the antigen with the monoclonal antibody stimulates intracellular calcium levels and the synthesis of cytokines. CD59 is an NKp46 coreceptor (by physical association) together they activate cytotoxicity of human NK-cells, their engagement results in tyrosine phosphorylation of CD3-zeta chains associated with NKp46. Reduced cell surface expression of NKp46 and other NK-cell receptors is linked to the impaired NK-cell cytolytic function in viremic HIV-1 infection.

Synaptotagmin-4 (SYT4) is a part of the synaptotagmin proteins family. Synaptotagmins are a large gene family of synaptic vesicle type III integral membrane proteins that operate as regulators of both exocytosis and endocytosis and are involved in neurotransmitter secretion from small secretory vesicles. SYT4 is expressed in neuronal tissues, and has the highest mRNA levels in the hippocampus. The proximity of the SYT4 gene to markers of several psychiatric disorders implies an involvement of SYT4 in human disease such as pheochromocytoma, and parkinson's disease.