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Endothelial cells express three different vascular endothelial growth factor (VEGF) receptors, belonging to the family of receptor tyrosine kinases (RTKs). They are named VEGFR-1 (Flt-1), VEGFR-2 (KDR/Flk-1), VEGFR-3 (Flt-4). Their expression is almost exclusively restricted to endothelial cells, but VEGFR-1 can also be found on monocytes, dendritic cells and on trophoblast cells. The flt-1 gene was first described in 1990. The receptor contains seven immunoglobulin-like extracellular domains, a single transmembrane region and an intracellular splited tyrosine kinase domain. Compared to VEGFR-2 the Flt-1 receptor has a higher affinity for VEGF but a weaker signaling activity. VEGFR-1 thus leads not to proliferation of endothelial cells, but mediates signals for differentiation. Interestingly a naturally occuring soluble variant of VEGFR-1 (sVEGFR-1) was found in HUVE supernatants in 1996, which is generated by alternative splicing of the flt-1 mRNA. The biological functions of sVEGFR-1 still are not clear, but it seems to be an endogenous regulator of angiogenesis, binding VEGF with the same affinity as the full-length receptor.

G3BP1 belongs to the heterogeneous nuclear RNA-binding proteins and is also an element of the Ras signal transduction pathway. G3BP1 is one of the DNA-unwinding enzymes that favors partially unwound 3'-tailed substrates and is also able to unwind partial RNA/DNA and RNA/RNA duplexes in an ATP-dependent fashion. G3BP1 binds specifically to the Ras-GTPase-activating protein by associating with its SH3 domain. In addition, G3BP1 cleaves exclusively between cytosine and adenine and cleaves MYC mRNA preferentially at the 3'-UTR.

MDS1 is a transcriptional regulator and oncoprotein which takes part in hematopoiesis, development, cell differentiation, apoptosis and proliferation. MDS1 is able to interact with CTBP1, SMAD3, CREBBP, KAT2B, MAPK8, and MAPK9. Overexpression, as a result of translocation with the AML1 gene, is known to cause leukemia. A number of transcript variants encoding several different isoforms were found.

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.

Troponin I, (TNNI1) is a member of the troponin I family. Troponin complex has 3 subunits, TNNI1 known as the inhibitory Subunit which prevents the actin-myosin interactions and thus mediating striated muscle relaxation. TNNI1 combines with tropomyosin and regulates calcium sensitivity of striated muscles by structural modifications in actin-myosin complexes.

The conserved 76 amino acid protein ubiquitin (Ub) regulates a host of intracellular processes through its enzymatic conjugation to other cellular proteins.
Ubiquitination occurs through sequential steps catalyzed by activating (E1), conjugating (E2), and ligase (E3) enzymes. The final step results in the formation of an isopeptide bond between Ub’s C-terminal glycine residue (G76) and a lysine residue of the target protein, although N-terminal ubiquitination is also known.
Outcomes of this modification include destabilization of the conjugated protein, altered protein trafficking and functional modulation.
After targeting the protein for specific localizations, ubiquitin is released from the substrate by deubiquitinating enzymes.
A mutant ubiquitin, having a Gly to Ala substitution at the C-terminus (G76A ubiquitin) supported several downstream reactions of the proteolytic pathway but inhibits the deubiquitination process.
As consequence, the Ub derivative becomes irreversibly conjugated to protein, shifting the equilibrium between the bound and unbound form in the direction of conjugation, at the expense of the free form.

STBD1 has one carbohydrate binding type-20 (CBM20) domain and has the ability to bind to carbohydrates. STBD1 is highly expressed in cardiac and skeletal muscles.

Acireductone dioxygenase 1 (ADI1) is a part of the acireductone dioxygenase family of metal-binding enzymes, which are involved in methionine salvage. ADI1 regulates mRNA processing in the nucleus, and carries out different functions depending on its localization. Related pseudogenes have been defined on chromosomes 8 and 20. ADI1 down-regulates cell migration arbitrated by MMP14.

Growth arrest and DNA Damage-Inducible Protein (GADD45A) binds both Cdks and PCNA. GADD45A is involved in DNA replication and repair. GADD45A stimulates DNA excision repair in vitro and inhibits entry of cells into S phase. GADD45A may serve as a link between p53-dependent cell cycle checkpoint and DNA repair. The GADD45A gene belongs to a group of genes whose transcript levels are increased following stressful growth arrest conditions and treatment with DNA-damaging agents. GADD45A responds to environmental stresses by mediating activation of the p38/JNK pathway via MTK1/MEKK4 kinase. GADD45A binds to proliferating cell nuclear antigen.

Proteasome subunit beta type-9 (PSMB9) belongs to the proteasome B-type family which is a 20S core beta subunit. PSMB9 is positioned in the class II region of the MHC (major histocompatibility complex). Expression of the PSMB9 protein is induced by INFG and this gene product replaces catalytic subunit 1 (proteasome beta 6 subunit) in the immunoproteasome.

CD4 is a cell-surface glycoprotein found on the mature helper T cells and immature thymocytes, as well as on monocytes and macrophages. (Some cytotoxic T cells have CD4 protein as well.) Normally, about 65% of T cells in the blood are CD4+ (have CD4 protein protruding from their membrane). A mature T cell with either have CD4 or CD8, but not both. During one stage of development T cells develop CD4 and CD8 receptors, but they eventually are differentiated in the thymus and become more specialized.

Thioredoxins are small disulphide-containing redox proteins (within the conserved Cys-Gly-Pro-Cys active site) that have been found in all the kingdoms of living organisms. Thioredoxin contains a single disulfide active site and serves as a general protein disulphide oxidoreductase. Thioredoxins are involved in the first unique step in DNA synthesis. It interacts with a broad range of proteins by a redox mechanism based on reversible oxidation of two cysteine thiol groups to a disulphide, accompanied by the transfer of two electrons and two protons. The net result is the covalent interconversion of a disulphide and a dithiol. It has been suggested that thioredoxin may catalyze the formation of correct disulfides during protein folding because of its ability to act as an efficient oxidoreductant. Trx also provides control over a number of transcription factors affecting cell proliferation and death through a mechanism referred to as redox regulation.

This gene is a member of a family of neurotrophic factors, neurotrophins that control survival and differentiation of mammalian neurons. The expression of this gene is ubiquitous and less influenced by environmental signals. While knock-outs of other neurotrophins including nerve growth factor, brain-derived neurotrophic factor, and neurotrophin 3 prove lethal during early postnatal development, NTF5-deficient mice only show minor cellular deficits and develop normally to adulthood.

Frataxin is a mitochondrial iron binding protein that is part of the FRATAXIN family. Frataxin functions in regulating mitochondrial iron transport and respiration. The expansion of intronic trinucleotide repeat GAA results in Friedreich ataxia. Frataxin plays a role in iron homeostasis. Frataxin is an anti-apoptotic protein which prevents mitochondrial damage and reactive oxygen species (ROS) production.

GAGE2A is a member of a multigene family expressed in a large variety of tumors while in normal tissues; expression is limited to germ cells. These genes organized in clustered repeats, have a high degree of predicted sequence identity, however differ by scattered single nucleotide change. Their sequences have either the antigenic peptide YRPRPRRY or YYWPRPRRY which is recognized by cytotoxic T-cells.

EPH Receptor B1 (EPHB1) is a member of the ephrin receptor subfamily of the proteintyrosine kinase family which 16 receptors are known. EPHB1 binds ephrin-B2, ephrin-B1,ephrin‑A3,ephrin-A1,ephrin-B3 and ephrin-A4. EPHB1 binds tyrosine kinase and phosphorylates syndecan-2 and thisphosphorylation is necessary for syndecan-2 clustering and spine formation. Ephrin receptors and theirligands (the ephrins) mediate several developmental processes, mainly in the nervous system.

IL2 is a secreted cytokine that is important for the proliferation of T and B lymphocytes. The receptor of this cytokine is a heterotrimeric protein complex whose gamma chain is also shared by interleukin 4 (IL4) and interleukin 7 (IL7). The expression of this gene in mature thymocytes is monoallelic, which represents an unusual regulatory mode for controlling the precise expression of a single gene. The targeted disruption of a similar gene in mice leads to ulcerative colitis-like disease, which suggests an essential role of this gene in the immune response to antigenic stimuli.

Stem cell factor / KIT ligand (SCF) is a cytokine which binds CD117 (c-Kit). SCF is also known as "steel factor" or "c-kit ligand". SCF exists in two forms, cell surface bound SCF and soluble (or free) SCF. Soluble SCF is produced by the cleavage of surface bound SCF by metalloproteases.
SCF is a growth factor important for the survival, proliferation, and differentiation of hematopoietic stem cells and other hematopoietic progenitor cells. One of its roles is to change the BFU-E (burst-forming unit-erythroid) cells, which are the earliest erythrocyte precursors in the erythrocytic series, into the CFU-E (colony-forming unit-erythroid).

PSMB6 belongs to the proteasome B-type family (T1B family) which is a 20S core beta subunit in the proteasome. The PSMB6 is not present in the immunoproteasome and is replaced by PSMB9. The proteasome is a multicatalytic proteinase complex with an extremely ordered ring-shaped 20S core structure. The core structure is comprised of 4 rings of 28 non-identical subunits; 2 rings are composed of 7 alpha subunits and 2 rings are composed of 7 beta subunits.

Histamine N-Methyltransferase or HNMT, is located in the cell cytosol. Sadenosyl-L-methionine acts as a methyl donor for HNMT which inactivates histamine. By inactivation of histamine, it affects the immune system’s response. HNMT acts on histamine in body tissues such as kidney, central nervous system and bronchus. The protein has a crucial part in the airway response to histamine & histamine degradation process and regulation.

The NOP16 protein is transcriptionally regulated by c-Myc and upregulated in breast cancer. NOP16 overexpression is linked with poor patient survival.

Cardiotrophin 1 (CT-1) is a 201 amino acid member of the interleukin-6 superfamily. It was identified by its ability to induce hypertrophic response in cardiac myocytes. CT-1 mRNA levels were found both in cardiac myocytes and in cardiac nonmyocytes. CT 1 was also detected in abundance in normal adult human lung and was expressed in both fetal and adult airway smooth muscle cells. CT 1 activates gp130 dependent signaling and stimulates the Janus kinase/signal transducers and activators of transcription (JAK/STAT) pathway to transduce hypertrophic and cytoprotective signals in cardiac myocytes.
CT 1 has also a neurotrophic function. CTF1 deficiency causes increased motoneuron cell death in spinal cord and brainstem nuclei of mice during a period between embryonic day 14 and the first postnatal week. Moreover, CT-1 is a hepatocyte survival factor that efficiently reduces hepatocellular damage in animal models of acute liver injury. Cardiotrophin 1 expression is augmented after hypoxic stimulation and it can protect cardiac cells when added either prior to simulated ischaemia or at the time of reoxygenation following simulated ischaemia. Cardiotrophin 1 can induce expression of the protective heat shock proteins (hsps) in cardiac cells.
Cardiotrophin-1 increased ventricular expression of ANP, brain natriuretic peptide (BNP) and angiotensinogen mRNA.
Cardiophin 1 levels were significantly elevated in patients with heart failure, patients with dilatative cardiomyopathy, moderate/severe mitral regurgitation, stable and unstable angina and after acute myocardial infarction.

Fucosyltransferase 3 (FUT3) catalyzes alpha-1, 3 and alpha-1, 4 glycosidic linkages which take part in the expression of Vim-2, Lewis A, Lewis B, sialyl Lewis X and Lewis X/SSEA-1 antigens. FUT3 takes part in blood group Lewis determination; Lewis-positive (Le+) individuals have an active enzyme while Lewis-negative (Le-) individuals have an inactive enzyme. FUT3 also operates on the corresponding 1, 4-galactosyl derivative, creating1, 3-L-fucosyl links.