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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/ 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.

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. 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 signaling 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 occuring, secreted forms of VEGFR-2 have so far been reported. The binding of VEGF165 to VEGFR-2 is dependent on heparin.

Neuregulin/Heregulin is a family of structurally related polypeptide growth factors which are stemmed from alternatively spliced genes (NRG1, NRG2, NRG3 and NRG4). There are more than 14 soluble and transmembrane proteins derived from the NRG1 gene. Proteolytic processing of the extracellular domain of the transmembrane NRG1 isoforms release soluble growth factors. These isoforms contain the heregulins (HRGs), glial growth factors (GGFs) and sensory and motor neuron-derived factor (SMDF). All these factors have the Ig and EGF-like domain, and are able to bind to ErbB3 and ErbB4 receptor tyrosin kinases. This binding stimulates erb3 and erb4 heterodimerization with erb2, promoting intrinsic kinase activity, which results in tyrosine phosphorylation. NRG1 isoforms induce the growth and differentiation of epithelial, neuronal, glial, and other types of cells.

GLO1 is involved in the catalysis and formation of S-lactoyl-glutathione from methylglyoxal condensation and reduced glutatione. GLO1 is linked to HLA and is localized to 6p21.3-p21.1, between HLA and the centromere. GLO1 enzyme is ubundantly expressed and present in numerous tumor cell lines, in which its concentration is often upregulated ubiquitisly. GLO1 is a major susceptible gene for autism in an ethnic Chinese population from Taiwan. GLO1 might be involved in the pathophysiology of mood disorders. GLO1 plays a role in the pathophysiology of mood disorders. Overexpression of GLO1 is associated with kidney tumor.

GLUL catalyzes the synthesis of glutamine from glutamate and ammonia. Glutamine is a major source of energy and that takes part in cell proliferation, inhibition of apoptosis, and cell signaling. GLUL is expressed during early fetal stages, and has a role in maintaining body pH by removing ammonia from circulation. Mutations in GLUL gene are related with congenital glutamine deficiency.

GLUL catalyzes the synthesis of glutamine from glutamate and ammonia. Glutamine is a major source of energy and that takes part in cell proliferation, inhibition of apoptosis, and cell signaling. GLUL is expressed during early fetal stages, and has a role in maintaining body pH by removing ammonia from circulation. Mutations in GLUL gene are related with congenital glutamine deficiency.

Acyl-CoA synthetase family member 2, also known as ACSF2 is a member of the ATP-dependent AMP-binding enzyme family. Acyl-CoA synthetases are a family of enzymes which catalyze the thioesterification of fatty acids with coenzymeA to form activated intermediates, which play a basic part in lipid metabolism as well as homeostasis of lipid-related processes. ACSF2 is required for the complex of lipid synthesis, energy production via beta-oxidation, protein acylation and fatty-acid dependent transcriptional regulation. Moreover, ACSF2 is required for fatty acid import into cells by the process of vectorial acylation.

DCN1-like protein 2 (DCUN1D2) which contains one DCUN1 domain and 1 UBA-like domain, may have a role in the neddylation of cullins which regulate SCF-type ubiquitin ligase complexes. The gene encoding Dcun1D2 is located on human chromosome 13. Chromosome 13 contains major tumor suppressor genes, including BRCA2 and RB1, which are linked with breast cancer susceptibility and retinoblastoma, respectively.

DiGeorge syndrome critical region gene 6 (DGCR6) shares homology with the Drosophila melanogaster gonadal protein, that participates in gonadal and germ cell development, and also with the gamma-1 subunit of human laminin. DGCR6 is involved in DiGeorge syndrome pathology and in schizophrenia.

TIE-1 (tyrosine kinase with Ig and EGF homology domains 1) and TIE-2/Tek comprise a receptor tyrosine kinase (RTK) subfamily with unique structural characteristics: two immunoglobulin-like domains flanking three epidermal growth factor (EGF)-like domains and followed by three fibronectin type III-like repeats in the extracellular region and a split tyrosine kinase domain in the cytoplasmic region. These receptors are expressed primarily on endothelial and hematopoietic progenitor cells and play critical roles in angiogenesis, vasculogenesis and hematopoiesis. Human TIE-1 cDNA encodes a 1122 amino acid (aa) residue precursor protein with an 18 residue putative signal peptide, a 726 residue extracellular domain and a 353 residue cytoplasmic domain. Two ligands, angiopoietin-1 (Ang1) and angiopoietin-2 (Ang2), which bind TIE-2 with high-affinity have been identified. Ang2 has been reported to act as an antagonist for Ang1. Mice engineered to overexpress Ang2 or to lack Ang1 or Tie-1 display similar angiogenic defects.

Profilin-1 also known as Pfn1 is a ubiquitous actin monomer-binding protein which is a member of the profilin family. Pfn1 significantly enhances skin wound healing in-vitro as well as in-vivo which is mediated by purinergic receptors. Furthermore, Pfn1 is also active in endothelial cell migration and vessel sprouting. Pfn1 is considered to regulate actin polymerization in response to extracellular signals.

TIE-1 (tyrosine kinase with Ig and EGF homology domains 1) and TIE-2/Tek comprise a receptor tyrosine kinase (RTK) subfamily with unique structural characteristics: two immunoglobulin-like domains flanking three epidermal growth factor (EGF)-like domains and followed by three fibronectin type III-like repeats in the extracellular region and a split tyrosine kinase domain in the cytoplasmic region. These receptors are expressed primarily on endothelial and hematopoietic progenitor cells and play critical roles in angiogenesis, vasculogenesis and hematopoiesis. Human TIE-1 cDNA encodes a 1124 amino acid (aa) residue precursor protein with an 18 residue putative signal peptide, a 727 residue extracellular domain and a 354 residue cytoplasmic domain. Whereas two ligands have been described for TIE-2 [angiopoietin-1 (Ang1) and angiopoietin-2 (Ang2)], so far no ligand was found for TIE-1.

Immunity-related GTPase family M protein (IRGM) is essential for clearance of severe protozoan and bacterial infections. IRGM belongs to the p47 immunity-related GTPase family. IRGM serves in innate immune response possibly via regulation of autophagy. IRGM regulates proinflammatory cytokine production and inhibit endotoxemia upon infection and also has a part in macrophages adhesion and motility. Polymorphisms which modify the natural expression of the IRGM gene are associated with a susceptibility to Crohn's disease and tuberculosis.

Killer-cell immunoglobulin-like receptors (KIRs), are a family of cell surface glycoproteins found on Natural Killer (NK) Cells, which are important cells of the immune system. They control the killing function of these cells by interacting with MHC class I molecules, which are expressed on all cell types. This interaction allows them to identify virally infected cells or tumor cells that have a distinctive low level of Class I MHC on their surface. The majority of KIRs are inhibitory, which means that their recognition of MHC suppresses the cytotoxic activity of their NK cell. Only a limited number of KIRs have the capacity to activate cells.
The KIR genes are found in a cluster on chromosome 19q13.4 within the 1 Mb leukocyte receptor complex (LRC). KIR molecules are extremely polymorphic, meaning their gene sequences differ significantly between individuals, so that different individuals have different arrays/repertoires of KIR genes.
The KIR proteins are categorized by the number of extracellular immunoglobulin domains (2D or 3D) and by whether they have a long (L) or short (S) cytoplasmic domain. KIR proteins with the long cytoplasmic domain transduce inhibitory signals upon ligand binding via an immune tyrosine-based inhibitory motif (ITIM). Whereas KIR proteins with the short cytoplasmic domain lack the ITIM motif and instead associate with the TYRO protein tyrosine kinase binding protein to transduce activating signals.
KIR2DS4 is an activating Killer Cell Ig-like Receptor (KIR, previously called p50 KIR, p50.3, cl39, or KAR-K1), which may recognize class I MHC molecules. KIR2DS4 does not inhibit the activity of NK cells.

POU6F1 is a member of the POU transcription factor family. POU6F1 is transcription factor that binds favorably to a variant of the octamer motif (5'-ATGATAAT-3'). POU6F1 is exclusively expressed in the embryo in the developing brain, however in the adult its expression is confined to the brain, heart, skeletal muscle and lung. In the brain, the highest expression levels are found in specific cell layers of the cortex, the olfactory bulb, the hippocampus and the cerebellum.

PPIF is a part of the peptidyl-prolyl cis-trans isomerase (PPIase) family. PPIF accelerates the folding of proteins. It catalyzes the cis-trans isomerization of proline imidic peptide bonds in oligopeptides. PPIF is key component of the mitochondrial permeability transition pore in the inner mitochondrial membrane. Activation of this pore is thought to be involved in the induction of apoptotic and necrotic cell death.

Chemokine (C-X-C motif) ligand 3 (CXCL3) is a small cytokine belonging to the CXC chemokine family that is also known as GRO3 oncogene (GRO3), GRO protein gamma (GROg) and macrophage inflammatory protein-2-beta (MIP2b). CXCL3 controls migration and adhesion of monocytes and mediates it effects on its target cell by interacting with a cell surface chemokine receptor called CXCR2. The gene for CXCL3 is located on chromosome 4 in a cluster of other CXC chemokines.

The somatomedins, or insulin-like growth factors (IGFs), comprise a family of peptides that play important roles in mammalian growth and development. IGF1 mediates many of the growth-promoting effects of growth hormone (GH; MIM 139250). Early studies showed that growth hormone 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' (Daughaday et al., 1972). Three main somatomedins have been characterized: somatomedin C (IGF1), somatomedin A (IGF2; MIM 147470), and somatomedin B (MIM 193190) (Rotwein, 1986; Rosenfeld, 2003).

γ-synuclein (Originally known as a breast cancer specific gene product, BCSG1) is an acidic neuronal protein of 127 amino acids. Gamma-Synuclein is a member of the Synuclein protein family, which is believed to be involved in the pathogenesis of neurodegenerative diseases. High levels of Gamma-Synuclein have been found in advanced breast carcinomas suggesting a correlation between overexpression of SNCG and breast tumor development. Synuclein-Gamma is found mostly in the peripheral nervous system (in primary sensory neurons, sympathetic neurons, and motor neurons) and retina. SNCG is also identified in the brain, ovarian tumors, and in the olfactory epithelium. SNCG expression in breast tumors is a marker for tumor progression. A modification in the expression of gamma-synuclein has been detected in the retina of Alzheimer''s patients.

PPIF is a part of the peptidyl-prolyl cis-trans isomerase (PPIase) family. PPIF accelerates the folding of proteins. It catalyzes the cis-trans isomerization of proline imidic peptide bonds in oligopeptides. PPIF is key component of the mitochondrial permeability transition pore in the inner mitochondrial membrane. Activation of this pore is thought to be involved in the induction of apoptotic and necrotic cell death.

EXO2 is a 3'-to-5' exonuclease specific for small (primarily 5 nucleotides or less in length) single-stranded RNA and DNA oligomers. RNA Exonuclease 2 (REXO2) takes part in DNA repair, replication, and recombination, and in RNA processing and degradation. EXO2 is involved in resistance of human cells to UV-C-induced cell death via its part in the DNA repair process.

Insulin-like growth factor II (IGF-II) is an important foetal growth hormone.IGF-II is made by theca cells during gestation. IGF-II binds the sink IGF-II receptor (IGF2R) which results in IGF-II degradation.IGF-II also engages the IGF-I receptor (IGF1R) to arbitrate embryonic growth.

Fibroblast Growth Factor-5 (FGF5) belongs to the FGF family of mitogenic peptides. In vitro, rhFGF5 is a mitogen for Balb/3T3 fibroblasts and bovine heart endothelial cells. FGF5 is also a major muscle-derived survival factor for cultured spinal motoneurons. In vivo, FGF5 is assumed to play central roles in both embryology and neurobiology. Developmentally, FGF5 mRNA is originally found in the embryoblast followed by the lateral somatic mesoderm, where it may play a part in angiogenesis, as well as the myotomes cranial to the tail region, where it may delay terminal myoblast differentiation during cell migration.

IFN Regulatory Factor-5, also known as IRF5 belongs to the IFN regulatory factor (IRF) family, a group of transcription factors with various functions, including virus-mediated activation of IFN, and modulation of cell growth, differentiation, apoptosis, and immune system activity. Members of the IRF family are characterized by a conserved N-terminal DNA-binding domain containing tryptophan (W) repeats. Multiple transcript variants encoding different isoforms have been found for this gene. In addition, IRF5 is implicated in the induction of IFNs IFNA and INFB and inflammatory cytokines upon virus infection. IRF5 is activated by TLR7 or TLR8 signaling.