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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/macrophage migration, 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 mitogenesis and 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.

EDA2R (ectodysplasin A2 receptor) mediates the activation of the NF-kappa-B and JNK pathways. Activation seems to be mediated through binding to TRAF3 and TRAF6. In addition, Mutations in EDA give rise to a clinical syndrome characterized by loss of hair, sweat glands, and teeth. EDA2R specifically binds to EDA-A2 isoform. This protein is a type III transmembrane protein of the TNFR (tumor necrosis factor receptor) superfamily, and contains 3 cysteine-rich repeats and a single transmembrane domain however it lacks an N-terminal signal peptide. Alternatively spliced transcript variants have been found for this gene. Among the diseases associated with EDA2R are ectodermal dysplasia 1, hypohidrotic, x-linked, and hypohidrotic ectodermal dysplasia.

Clusterin also named Apolipoprotein J (APO-J) is a 75-80 kD disulfide-linked heterodimeric protein containing about 30% of N-linked carbohydrate rich in sialic acid but truncated forms targeted to the nucleus have also been identified.
The precursor polypeptide chain is cleaved proteolytically to remove the 22-mer secretory signal peptide and subsequently between residues 227/228 to generate the a and b chains. These are assembled in anti-parallel to give a heterodimeric molecule in which the cysteine-rich centers are linked by five disulfide bridges and are flanked by two predicted coiled-coil a-helices and three predicted amphipathic a-helices.
Across a broad range of species clusterin shows a high degree of sequence homology ranging from 70% to 80%. It is nearly ubiquitously expressed in most mammalian tissues and can be found in plasma, milk, urine, cerebrospinal fluid and semen.
It is able to bind and form complexes with numerous partners such as immunoglobulins, lipids, heparin, bacteria, complement components, paraoxonase, beta amyloid, leptin and others. Clusterin has been ascribed a plethora of functions such as phagocyte recruitment, aggregation induction, complement attack prevention, apoptosis inhibition, membrane remodeling, lipid transport, hormone transport and/or scavenging, matrix metalloproteinase inhibition.
A genuine function of clusterin has not been defined. One tempting hypothesis says that clusterin is an extracellular chaperone protecting cells from stress induced insults caused by degraded and misfolded protein precipitates.
Clusterin is up- or down regulated on the mRNA or protein level in many pathological and clinically relevant situations including cancer, organ regeneration, infection, Alzheimer disease, retinitis pigmentosa, myocardial infarction, renal tubular damage, autoimmunity and others.

Ectonucleoside Triphosphate Diphosphohydrolase 3, also known as ENTPD3, which owns a threefold preference for the hydrolysis of ATP over ADP is similar to E-type nucleotidases (NTPases). ENTPD3 is a protein coding gene which contains four apyrase-conserved areas which is characteristic of NTPases.

SEC13 is a member of the SEC13 family of WD-repeat proteins. SEC13 is a constituent of the endoplasmic reticulum and the nuclear pore complex. SEC13 is similar to the yeast SEC13 protein that is essential for vesicle biogenesis from endoplasmic reticulum during the transport of proteins. SEC13 interacts with SEC31A and SEC31B. SEC31A colocalizes with SEC13, one of the other components of COPII, in the subcellular structures corresponding to the vesicle transport function.

HSP90 has been identified in the cytosol, nucleus and endoplasmic reticulum, and is reported to exist in many tissue types. In several tissues, including smooth muscle, HSP90 comprises up to 2% of total cellular protein. HSP90 functions as a dimer, assembled as part of heterocomplex. It possesses ATP-binding site and low ATPase activity. HSP90 is able to associate with actin filaments in certain conditions. Another important property of HSP90 is the binding of unoccupied steroid hormone receptors. HSP90 has been characterized as a molecular chaperone able to keep the target protein in a folding-competent state. It has an enhanced chaperone activity in oligomeric form at high temperatures. HSP90 function is sensitive to bivalent cations concentration.

IL-1 alpha is produced by activated macrophages, stimulates thymocyte proliferation by inducing il-2 release, b-cell maturation and proliferation, and fibroblast growth factor activity. IL1A proteins are involved in the inflammatory response, being identified as endogenous pyrogens, and are reported to stimulate the release of prostaglandin and collagenase from synovial cells.

STC2 is a homodimeric glycoprotein that is expressed in a wide variety of tissues and may have autocrine or paracrine functions. The encoded protein has 10 of its 15 cysteine residues conserved among stanniocalcin family members and is phosphorylated by casein kinase 2 exclusively on its serine residues. Its C-terminus contains a cluster of histidine residues which may interact with metal ions. The protein may play a role in the regulation of renal and intestinal calcium and phosphate transport, cell metabolism, or cellular calcium/phosphate homeostasis. Constitutive over expression of human stanniocalcin 2 in mice resulted in pre- and postnatal growth restriction, reduced bone and skeletal muscle growth, and organomegaly. Expression of this gene is induced by estrogen and altered in some breast cancers.

N-Acetylglucosamine Kinase (NAGK) is a part of the eukaryotic-type N-acetylglucosamine kinase family. NAGK transforms endogenous N-acetylglucosamine (GlcNAc), a main component of complex carbohydrates, from lysosomal degradation or nutritional sources into GlcNAc 6-phosphate. NAGK is a significant salvage enzyme of amino sugar metabolism in mammals which has ManNAc kinase activity.

PPME1 catalyzes the demethylation and inactivation of protein phosphatase (PP2A), a multimeric phosphoserine/ threonine protein phosphatase related to growth inhibition and cell cycle arrest. PPME1 can demethylate PP2A catalytic subunit in vitro and okadaic acid treatment can inhibit this reaction. It is conserved from yeast to human and holds a motif found in lipases having a catalytic triad activated serine as their active site nucleophile.

RAB10, Member RAS Oncogene Family (RAB10) belongs to the Ras superfamily of small GTP-binding proteins. RAB10 is a key regulator of endocytic recycling, particularly in the basolateral recycling pathways of polarized epithelial cells. It is required for the recruitment of CNT-1 to endosomal membranes in the intestinal epithelium.

Secreted frizzled-related protein 4 (SFRP4) belongs to the SFRP family which contains a cysteine-rich domain homologous to the putative Wnt-binding site of Frizzled proteins. SFRPs serve as soluble modulators of Wnt signaling. SFRP4 may serve as a regulator of adult uterine morphology and function. SFRP4 increases apoptosis during ovulation possibly via modulation of FZ1/FZ4/WNT4 signaling. SFRP4 also has phosphaturic effects by specifically inhibiting sodium-dependent phosphate uptake. SFRP4 is expressed in proliferative endometrium and several types of ovarian, endometrial and Brest tumors. SFRP4 is expressed in mesenchymal cells and in cardiomyocytes. SFRP4 expression in ventricular myocardium correlates with apoptosis related gene expression. SFRP4 is up-regulated in failing myocardium.

FGF-23 is a member of the fibroblast growth factor (FGF) family. FGF family members possess broad mitogenic and cell survival activities and are involved in a variety of biological processes including embryonic development, cell growth, morphogenesis, tissue repair, tumor growth and invasion. FGF-23 inhibits renal tubular phosphate transport. The FGF-23 gene was identified by its mutations associated with autosomal dominant hypophosphatemic rickets (ADHR), an inherited phosphate wasting disorder. Abnormally high level expression of FGF-23 was found in oncogenic hypophosphatemic osteomalacia (OHO), a phenotypically similar disease caused by abnormal phosphate metabolism. FGF-23 mutations have also been shown to cause familial tumoral calcinosis with hyperphosphatemia.

Cytochrome c oxidase assembly factor 4 (COA4) is the last enzyme of the mitochondrial respiratory chain which needs a great number of accessory factors. COA4 is vital for oxidative phosphorylation and comprises multiple complexes including cytochrome c oxidase, assembled in macromolecular supercomplexes. COX4 is a protein-coding gene which defect in it causes an acute human encephalomyopathies.

STK17A belongs to the DAP kinase-associated apoptosis-inducing protein kinase family and encodes an autophosphorylated nuclear protein with a protein kinase domain. STK17A acts as a positive regulator of apoptosis. STK17A is greatly expressed in the placenta with lower levels in the heart, lung, skeletal muscle, kidney and pancreas.

Twisted gastrulation Protein (TSG) is a secreted, cysteine-rich protein which has a role in dorsal/ventral patterning in Drosophila and Xenopus by regulating BMP signaling. TSG functions as an agonist for BMP signaling by controlling the inhibitory actions of the BMP antagonist, Chordin/Sog, and the cleavage properties of the metalloprotease, xolloid/tolloid. TSG N-terminal domain binds BMP protein directly and displays BMP antagonist activity.

GDNF family receptor alpha-1 (GFRA1) belongs to the GDNF receptor family. GFRA1 is a glycosyl-phosphatidylinositol(GPI)-linked cell surface receptor for both Glial cell line-derived growth factor (GDNF), neurturin (NTN), and mediates activation of the RET tyrosine kinase receptor. The GFRA1 protein is a potent survival factor for central and peripheral neurons, and is vital for the development of kidneys and the enteric nervous system.

SARS Coronavirus is an enveloped virus containing 3 outer structural proteins, namely the membrane (M), envelope (E), and spike (S) proteins. Spike (S)-glycoprotein of the virus interacts with a cellular receptor and mediates membrane fusion to allow viral entry into susceptible target cells. Accordingly, S-protein takes part in virus infection cycle and is the primary target of neutralizing antibodies.

RAB39B, Member RAS Oncogene Family (RAB39B) belongs to the Rab family of proteins. Rab proteins are small GTPases, which are involved in vesicular trafficking. RAB39B gene mutations are linked with X-linked mental retardation.

SPARC-like protein 1 or SPARC1 is an anti-adhesive protein with a similarity to the SPARC protein’s structure. SPARC1 is highly expressed in several tissues such as brain, lungs, kidney, heart, although it is not found in the liver tissue. The protein inhibits spreading or adhesion of many substrates and is considered to lead to antiadhesive signaling that stops neuronal migration, that occurs during development or as a trauma response, consistent with production by glial and neuronal cells.

The FGFs are a family of more than 20 small (~17–26 kDa) secreted peptides. The initial characterization of these proteins focused on their ability to stimulate fibroblast proliferation. This mitogenic activity was mediated through FGF receptors (FGFRs) 1, 2, or 3. A fourth closely related tyrosine kinase receptor (FGFR4) was able to bind the FGFs but did not lead to a mitogenic response.
FGFs modulate cellular activity via at least 5 distinct subfamilies of high-affinity FGF receptors (FGFRs): FGFR-1, -2, -3, and -4, all with intrinsic tyrosine kinase activity and, except for FGFR-4, multiple splice isoforms, and FGFR-5, which lacks an intracellular kinase domain. There is growing evidence that FGFRs can be important for regulation of glucose and lipid homeostasis. The overexpression of a dominant negative form of FGFR-1 in ? cells leads to diabetes in mice, which thus implies that proper FGF signaling is required for normal ? cell function and glycemia maintenance. FGFR-2 appears to be a key molecule during pancreatic development. Moreover, FGFR-4 has been implicated in cholesterol metabolism and bile acid synthesis.
FGF-19, has been shown to cause resistance to diet-induced obesity and insulin desensitization and to improve insulin, glucose, and lipid profiles in diabetic rodents. Since these effects, at least in part, are mediated through the observed changes in metabolic rates, FGF-19 can be considered as a regulator of energy expenditure.
FGF-21 is preferentially expressed in liver, but an exact knowledge of FGF-21 bioactivity and its mode of action have been lacking to date. FGF-21 is a potent activator of glucose uptake on adipocytes, protects animals from diet-induced obesity when overexpressed in transgenic mice, and lowers blood glucose and triglyceride levels when therapeutically administered to diabetic rodents.

Thymic Stromal Lymphopoietin Receptor (TSLPR) is a member of the type I cytokine receptor family. TSLPR alongside the interleukin 7 receptor (IL7R) activate STAT3, STAT5, and JAK2 pathways, which is regulated processes such as cell proliferation and development of the hematopoietic system. Two transcript variants encoding dissimilar isoforms have been found for this gene. TSLPR is expressed in heart, skeletal muscle, kidney and adult and fetal liver.

LIN28 plays an important role as a 'translational enhancer', leading specific mRNAs to polysomes and therefore increasing the competence of protein synthesis. LIN28 is a marker of undifferentiated human embryonic stem cells and it enhances the efficiency of the formation of induced pluripotent stem (iPS) cells from human fibroblasts. LIN28 binds to the let-7 pre-miRNA and blocks production of the mature let-7 microRNA in mouse embryonic stem cells. Overexpression of LIN28 is associated with human germ-cell tumors.