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PDGFRa is a cell surface tyrosine kinase receptor for PDGF family members. PDGFRa binds to both A and B subunits of PDGF. It is known that PDGFRa is vital for kidney development since mice heterozygous for the receptor display defective kidney phenotypes.

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), and VEGFR-3 (Flt-4). Their expression is almost exclusively restricted to endothelial cells, but VEGFR-1 can also be found on monocytes. All VEGF-receptors have seven immunoglobulin-like extracellular domains, a single transmembrane region and an intracellular split tyrosine kinase domain. VEGFR-2 has a lower affinity for VEGF than the Flt-1 receptor, but a higher signalling activity. Mitogenic activity in endothelial cells is mainly mediated by VEGFR-2 leading to their proliferation. Differential splicing of the flt-1 gene leads to the formation of a secreted, soluble variant of VEGFR-1 (sVEGFR-1). No naturally occurring, secreted forms of VEGFR-2 have so far been reported. The binding of VEGF165 to VEGFR-2 is dependent on heparin.

TNFSF15 is a cytokine that belongs to the tumor necrosis factor (TNF) ligand family. This protein is abundantly expressed in endothelial cells, but is not expressed in either B or T cells. The expression of TNFSF15 is inducible by TNF and IL-1 alpha. This cytokine is a ligand for receptor TNFRSF25 and decoy receptor TNFRSF21/DR6. It can activate NF-kappaB and MAP kinases, and acts as an autocrine factor to induce apoptosis in endothelial cells. TNFSF15 is also found to inhibit endothelial cell proliferation, and thus may function as an angiogenesis inhibitor. An additional isoform encoded by an alternatively spliced transcript variant has been reported but the sequence of this transcript has not been determined.

Tyrosine 3-monooxygenase (Th), is a rate-limiting enzyme in catecholamine synthesis. Th utilizes tetrahydrobiopterin as well as molecular oxygen to convert tyrosine to DOPA. Th regulates dopamine (DA) neurotransmission at the biosynthesis and reuptake steps. Th takes a vital part in the physiology of adrenergic neurons. Furthermore, Th effects overexpression in lymphocytes on the differentiation as well as function of T helper cells.

The epidermal growth factor receptor (EGF R) subfamily of receptor tyrosine kinases comprises four members: EGF R (also known as HER1, ErbB1 or ErbB), ErbB2 (Neu, HER-2), ErbB3 (HER-3), and ErbB4 (HER-4). All family members are type I transmembrane glycoprotein that has an extracellular domain which contains two cysteine-rich domains separated by a spacer region that is involved in ligand-binding, and a cytoplasmic domain which has a membrane-proximal tyrosine kinase domain and a C-terminal tail with multiple tyrosine autophosphorylation sites. The human EGF R gene encodes a 1210 amino acid (aa) residue precursor with a 24 aa putative signal peptide, a 621 aa extracellular domain, a 23 aa transmembrane domain, and a 542 aa cytoplasmic domain. EGF R has been shown to bind a subset of the EGF family ligands, including EGF, amphiregulin, TGF-a , betacellulin, epiregulin, heparin-binding EGF and neuregulin-2 in the absence of a co-receptor. Ligand binding induces EGF R homodimerization as well as heterdimerization with ErbB2, resulting in kinase activation, tyrosine phosphorylation and cell signaling. EGF R can also be recruited to form heterodimers with the ligand-activated ErbB3 or ErbB4. EGF R signaling has been shown to regulate multiple biological functions including cell proliferation, differentiation, motility and apoptosis. In addition, EGF R signaling has also been shown to play a role in carcinogenesis.

PKLR is a pyruvate kinase which catalyzes the transphosphorylation of phohsphoenolpyruvate into pyruvate and ATP. That is the rate-limiting step of glycolysis. PKLR gene encodes the L- and R-type isoenzymes through alternate splicing events controlled by different promoters. L-type isoform can also appear as a tetramer and is upregulated by glucose with implications in maturity-onset diabetes of the young.

The epidermal growth factor receptor (EGF R) subfamily of receptor tyrosine kinases comprises four members: EGF R (also known as HER1, ErbB1 or ErbB), ErbB2 (Neu, HER-2), ErbB3 (HER-3), and ErbB4 (HER-4). All family members are type I transmembrane glycoprotein that has an extracellular domain which contains two cysteine-rich domains separated by a spacer region that is involved in ligand-binding, and a cytoplasmic domain which has a membrane-proximal tyrosine kinase domain and a C-terminal tail with multiple tyrosine autophosphorylation sites. The human EGF R gene encodes a 1210 amino acid (aa) residue precursor with a 24 aa putative signal peptide, a 621 aa extracellular domain, a 23 aa transmembrane domain, and a 542 aa cytoplasmic domain. EGF R has been shown to bind a subset of the EGF family ligands, including EGF, amphiregulin, TGF-a , betacellulin, epiregulin, heparin-binding EGF and neuregulin-2 in the absence of a co-receptor. Ligand binding induces EGF R homodimerization as well as heterdimerization with ErbB2, resulting in kinase activation, tyrosine phosphorylation and cell signaling. EGF R can also be recruited to form heterodimers with the ligand-activated ErbB3 or ErbB4. EGF R signaling has been shown to regulate multiple biological functions including cell proliferation, differentiation, motility and apoptosis. In addition, EGF R signaling has also been shown to play a role in carcinogenesis.

Alpha 1-microglobulin (A1M) is a lipocalin superfamily member (kernal lipocalins). A1M is a low molecular weight protein component of plasma. A1M is distributed in plasma and extravascular compartments of all organs. Alpha-1 Microglobulin is found in mammals, birds, amphibians and fish. The primary sites of A1M synthesis are the liver and the kidney. Around the opening of the lipocalin pocket three lysyl residues are situated; those residues carry yellow-brown modification derived from the binding and degradation of heme and kynurenin (a tryptophan metabolite). A1-Microglobulin’s reductase and dehydrogenase have broad biological substrate specificity properties due to its’ free cysteine side-chain which is located in a flexible loop. Alpha-1-microglobulin is glycosylated by three separate carbohydrate chains: two complex carbohydrates which are N-linked to asparagines at residues 17 and 96, and the other simple carbohydrate which is O-linked to threonine at position 5. The carbohydrates comprise 22% of the total molecular mass of the protein. The glycosylation varies between species.
A1M exists in two forms- a free form and complexed to other macromolecules: in humans- complexed to immunoglobulin A (IgA), in rat- complexed to alpha-1-inhibitor-3. Free A1M is exceptionally heterogeneous in charge (therefore also known as protein HC), and is found tightly linked to a chromophore. The free Alpha-1-microglobulin is a monomeric protein composed of one 188 residue polypeptide and contains three cysteines, two of which (residues 75 and 173) form a conserved intra-molecular disulphide link. The chromophoric group is covalently bound to the free cysteine residue at position 34. A1M binds retinol as a major ligand, but this is probably distinct from its covalent chromophore.
Half of all human plasma A1M (approximately 0.03mg/ml) forms a 1:1 complex with about 5% of plasma immunoglobulin A. The resulting macromolecular complexes’ molecular weight is 200000, and a plasma concentration of 0.3mg/ml. The complex can exhibit both antibody activity and affect many of the biological actions of free Alpha-1-microglobulin.
Alpha-1-microglobulin was first discovered in pathological human urine.
It was suggested that A1M might be involved in tissue defense against reactive oxygen species, oxidation by heme and kynurenin. Evidence also suggests that A1M functions in the regulation of the immune system. Other functions include inhibition of stimulation of cultured lymphocytes by protein antigens; induction of cell division of lymphocytes, a mitogenic effect that can either be enhanced or inhibited by the action of other plasma components; inhibition of neutrophil granulocyte migration in vitro; and inhibition of chemotaxis.

Tumor necrosis factor is a member of a group of cytokines that all stimulate the acute phase reaction. TNF is involved in systemic inflammationand secreted mainly by macrophages.
TNF causes apoptotic cell death, cellular proliferation, differentiation, inflammation, tumorigenesis and 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.

WIF1 binds to wnt proteins and inhibits their activities. WIF1 plays a role in mesoderm segmentation. WNT proteins are extracellular signaling molecules that take part in the control of embryonic development & cancer. WIF1 protein contains a WNT inhibitory factor (WIF) domain and 5 epidermal growth factor (EGF)-like domains. WIF1 takes part in mesoderm segmentation. WIF1 protein is found to be present in fish, amphibia and mammals. WIF1 is a recurrent target in human salivary gland oncogenesis. Downregulation of WIF1 takes part in the development and progression of pleomorphic adenomas. WIF1 is a tumor suppressor, specifically in nonfunctioning pituitary tumors.

Human TNFRSF10A is a type 1 transmembrane protein in the TNF R superfamily. TNFRSF10A is not expressed in rodents. The trimeric ligand Trail binds TNFRSF10A and induces apoptosis, and recombinant, soluble forms of the receptor inhibit Trail-induced apoptosis. TNFRSF10A is expressed generally in damaged, infected, and malignant cells. TNFRSF10A functions in immune surveillance, inducing apoptosis in cancer cells but not normal cells.

PLGF is a growth factor active in angiogenesis, and endothelial cell growth, stimulating their proliferation and migration. It binds to receptor vegfr-1/flt1.

PGK1 is an X-linked enzyme that has a major role in the glycolytic pathway. PGK1 is a glycolytic enzyme which catalyzes the conversion of 1,3-diphosphoglycerate to 3-phosphoglycerate, generating an ATP molecule. PGK1 may also act as a cofactor for polymerase alpha. Defects in the PGK1 gene are usually associated with chronic hemolytic anemia, though it can be accompanied by either mental retardation or muscular disease (rhabdomyolysis). Overexpression of PGK1 and its signalling targets are possibly an expression-pathway in diffuse primary gastric carcinomas promoting peritoneal dissemination. It was shown that PGK1 is differentially expressed in the dorsolateral prefrontal cortex from patients with schizophrenia.

SDF-1 (stromal cell-derived factor-1) is small cytokine belonging to the chemokine family that is officially designated Chemokine (C-X-C motif) ligand 12 (CXCL12). It is produced in two forms, SDF-1?/CXCL12a and SDF-1?/CXCL12b, by alternate splicing of the same gene. Chemokines are characterized by the presence of four conserved cysteines, which form two disulfide bonds. The CXCL12 proteins belong to the group of CXC chemokines, whose initial pair of cysteines are separated by one intervening amino acid. CXCL12 is strongly chemotactic for lymphocytes and has been implicated as an important cell co-ordinator during development. During embryogenesis it directs the migration of hematopoietic cells from foetal liver to bone marrow. Mice which were knocked-out for CXCL12 gene were lethal before the birth or within just 1 hour of life. As another role, CXCL12a alters also the electrophysiology of neurons. CXCL12 was shown to be expressend in many tissues in mice (including brain, thymus, heart, lung, liver, kidney, spleen and bone marrow).
The receptor for this chemokine is CXCR4, which was previously called fusin. This CXCL12-CXCR4 interaction used to be considered exclusive (unlike for other chemokines and their receptors), but recently it was suggested that CXCL12 is also bound by CXCR7 receptor.
The gene for CXCL12 is located on human chromosome 10. In human and mouse both CXCL12 and CXCR4 show high identity of sequence: 99% and 90%, respectively.

Platelet factor-4 is a 70-amino acid protein that is released from the alpha-granules of activated platelets and binds with high affinity to heparin. Its major physiologic role appears to be neutralization of heparin-like molecules on the endothelial surface of blood vessels, thereby inhibiting local antithrombin III activity and promoting coagulation. As a strong chemoattractant for neutrophils and fibroblasts, PF4 probably has a role in inflammation and wound repair. Oncostatin-A is a member of the CXC chemokine family. Human PF4 is used for the proof of heparin-induced thrombocytopenia. Furthermore it is used as an inhibitor in the angiogenesis during tumor therapy.

Tumor necrosis factor receptor superfamily member 8 (TNFRSF8) is a receptor for TNFSF8/CD30L. TNFRSF8 has a role in the regulation of cellular growth and transformation of activated lymphoblasts. In addition, the TNFRSF8 protein regulates gene expression via activation of NF-kappa-B. TNFRSF8 being a regulator of apoptosis, induces cell death or proliferation, depending on the cell type.

Lipopolysaccharide-induced TNF-alpha factor (LITAF) is a small integral membrane protein of lysosome/late endosome. The expression of inflammatory cytokines such as TNF-alpha in Lipopolysaccharide-induced processes is mediated by LITAF. LITAF connects to STAT6B, which belongs to the STAT6 family forming a complex on the TNF-alpha promoter that modifies TNF activity. High levels of expression of LITAF mRNA are observed mostly in the placenta, peripheral blood leukocytes, lymph nodes and spleen.

The somatomedins, or IGFs, comprise a family of peptides that play important roles in mammalian growth and development. IGF1 mediates many of the growth-promoting effects of GH. Early studies showed that GH did not directly stimulate the incorporation of sulfate into cartilage, but rather acted through a serum factor, termed 'sulfation factor,' which later became known as somatomedin. Three main somatomedins have been characterized: somatomedin C (IGF1), somatomedin A (IGF2), and somatomedin B.

Activating transcription factor 4 (ATF4) is a member of a family of DNA-binding proteins which includes the AP-1 family of transcription factors, cAMP-response element binding proteins and CREB-like proteins. The ATF4 gene encodes a transcription factor which was initially identified as a widely expressed mammalian DNA binding protein that could bind a tax-responsive enhancer element in the LTR of HTLV-1.

VEGF-C, also known as Vascular Endothelial Growth Factor Related Protein (VRP), is a recently discovered VEGF growth factor family member that is most closely related to VEGF-D. Human VEGF-C cDNA encodes a pre-pro-protein of 416 amino acids residues. It is almost identical to the mouse VEGF-C protein. Similar to VEGF-D, VEGF-C has a VEGF homology domain spanning the middle third of the precursor molecule and long N- and C-terminal extensions. In adults, VEGF-C is highly expressed in heart, placenta, ovary and small intestine. Recombinant human VEGF-C, lacking the N- and C-terminal extensions and containing only the middle VEGF homology domain, forms primarily non-covalently linked dimers. This protein is a ligand for both VEGFR-2/KDR and VEGFR-3/FLT-4. Since VEGFR-3 is strongly expressed in lymphatic endothelial cells, it has been postulated that VEGF-C is involved in the regulation of the growth and/or differentiation of lymphatic endothelium. Although recombinant human VEGF-C is also a mitogen for vascular endothelial cells, it is much less potent than VEGF-A.

MMAB protein catalyzes the last step in the conversion of vitamin B(12) into adenosylcobalamin (AdoCbl), a vitamin B12 containing coenzyme for methylmalonyl-CoA mutase(MCM). Decreased MMAB activity leads to the inherited disorder vitamin B12 dependent methylmalonic aciduria linked to the cblB complementation group.

Sulfotransferase 1C4 (SULT1C4) is a member of the SULT subfamily. SULT1C4 is responsible for transferring a sulfo moiety from PAPS to phenol-containing compounds. Sulfotransferase enzymes catalyze the sulfate conjugation of many hormones, neurotransmitters, drugs, and xenobiotic compounds. Sulfotransferase enzymes are different in their tissue distributions and substrate specificities. SULT1C4 catalyzes the sulfonation of p-nitrophenol and N-hydroxy-2-acetylaminofluorene.