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TNFR2 belongs to the TNF-receptor superfamily. TNFR2 is receptor with high affinity for TNFSF2/TNF-alpha and approximately 5-fold lower affinity for homotrimeric TNFSF1/lymphotoxin-alpha. TNFR2 mediates the majority of the metabolic effects of TNF-alpha. In addition, knockout studies in mice propose a role for TNFR2 in protecting neurons from apoptosis by stimulating antioxidative pathways. TNFR2 expression might have a significant role in the angiogenesis, tumor cell proliferation and metastasis of Invasive micropapillary carcinoma of the breast.
There are 2 types of soluble TNF receptors: sTNFR-I and sTNFR-II, which act to neutralize the biological activities of TNF alpha and TNF beta. The levels of these soluble receptors seem to increase as a result of shedding of the extracellular domains of the membrane bound receptors. High levels of soluble TNF receptors are found in the amniotic fluid of pregnant women. TNFR2 and TNFR1 form a heterocomplex which mediates the recruitment of 2 anti-apoptotic proteins, c-IAP1 and c-IAP2, which possess E3 ubiquitin ligase activity. IAPs’ function in TNF-receptor signaling is unknown; nevertheless, c-IAP1 is believed to potentiate TNF-induced apoptosis by the ubiquitination and degradation of TNF-receptor-associated factor 2, which mediates anti-apoptotic signals. Oxidative stress promotes TNFR1 and TNFR2 self-interaction, ligand-independent and enhanced ligand-dependent TNF signaling. TNF-a, TNFR1 and TNFR2 have roles in cellular differentiation. TNFR1 and TNFR2 function in cell type-specific renal injury.

Members of the IFN regulatory factor (IRF) family regulate gene expression critical to immune response, hemopoiesis, and proliferation. IRF-3 is a member of the IRF family, and is distinct from other family members. Its transcriptional activity is regulated solely by posttranslational modifications. It plays a crucial role in activation of innate immunity and inflammation in response to viral infection. IRF-3 mediates IFN-stimulated response element (isre) promoter activation. Functions as a molecular switch for antiviral activity. Dsrna generated during the course of an viral infection leads to IRF3 phosphorylation on the c-terminal serine/threonine cluster. This induces a conformational change, leading to its dimerization, nuclear localization and association with creb binding protein (crebbp) to form dsrna-activated factor 1 (draf1), a complex which activates the transcription of genes under the control of isre. The complex binds to the ie and prdiii regions on the ifn-alpha and ifn-beta promoters respectively. IRF-3 does not have any transcription activation domains.

GTF2E2 is vital for transcription initiation by RNA polymerase II in conjunction with other general factors. General Transcription Factor IIE is a heterotetramer composed of two subunits of relatively high molecular mass 57,000 (GTF2E1) and two of 34,000 (GTF2E2). GTF2E2 is necessary in conjunction with GTF2E1 for transcription initiation. GTF2E2 recruits TFIIH to the initiation complex and stimulates the RNA polymerase II C-terminal domain kinase and DNA-dependent ATPase activities of TFIIH. Both TFIIE and TFIIH are essential for promoter clearance by RNA polymerase.

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.

Leukemia Inhibitory Factor also called LIF is a lymphoid factor that promotes long-term maintenance of embryonic stem cells by suppressing spontaneous differentiation. Leukemia Inhibitory Factor has several functions such as cholinergic neuron differentiation, control of stem cell pluripotency, bone & fat metabolism, mitogenesis of factor dependent cell lines & promotion of megakaryocyte production in vivo. Human and mouse LIF exhibit a 78% identity in its amino acid sequence.

Rho Guanine Nucleotide Exchange Factor 39, also known as ARHGEF39, is a protein coding gene which owns one DH (DBL-homology) domain and one PH domain. ARHGEF39 encourages cell proliferation.

The somatomedins, or insulin-like growth factors (IGFs), comprise a family of peptides that takes part in mammalian growth and development. IGF1 mediates various 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). 3 main somatomedins have been characterized: somatomedin C (IGF1), somatomedin A (IGF2; MIM 147470), and somatomedin B (MIM 193190) (Rotwein, 1986; Rosenfeld, 2003).

Pre-mRNA-splicing factor SYF2 (SYF2) may be involved in pre-mRNA splicing. The SYF2 protein interacts with cyclin D-type binding-protein 1, which is believed to be a cell cycle regulator at the G1/S transition. SYF2 is amply expressed in the heart, skeletal muscle and kidney and is expressed at lower levels in other tissues.

Eukaryotic translation elongation factor 1 epsilon-1 (EEF1E1) shares sequence similarity with the amino-terminal ends of the Beta and Gamma subunits of EF-1. By specifically interacting with MetRS, EEF1E1 binds to a macromolecular tRNA synthtase complex which catalyzes the ligation of specific amino acids to their cognate tRNAs. Upon DNA damage, EEF1E1 translocates to the nucleus where it interacts with ATM and ATR, resulting in p53 activation.

Fibroblast Growth Factors (FGFs) comprise a family of at least eighteen structurally realted proteins that are involved in a multitude of physiological and pathological cellular processes, including cell growth, differentation, angiogenesis, wound healing and tumorgenesis. The biological activities of the FGFs are mediated by a family if type I transmembrane tyrosine kinases which undergo dimerization and autophosphorylation after ligand binding. Four distinct genes encoding closely related FGF receptors, FGFR-1to -4 are known. Multiple forms of FGFR-1 to -3 are generated by alternative splicing of the mRNAs. A frequent splicing event involving FGFR-1 and -2 results in receptors containing all three Ig domains, referred to as the alpha isoform, or only IgII and IgIII, referred to as the ? isoform. Only the alpha isoform has been identified for FGFR-3 and FGFR-4. Additional splicing events for FGFR-1 to -3, involving the C-terminal half of the IgIII domain encoded by two mutually exclusive alternative exons, generate FGF receptors with alternative IgIII domains (IIIb and IIIc). A IIIa isoform which is a secreted FGF binding protein containing only the N-terminal half of the IgIII domain plus some intron sequences has also been reported for FGFR-1. Mutations in FGFR-1 to -3 have been found in patients with birth defects involving craniosynostosis.

Growth Differentiation Factor-7 (GDF-7) belongs to the BMP family of TGF-b superfamily proteins. GDF7 elicits its bioactivity via a heterodimeric receptor complex comprised of a type 1 (BMPR-IB) and a type II (BMPR-II or Activin RII) serine/threonine kinase receptor. GDF7 signaling results in the phosphorylation and activation of Smad proteins. GDF-7 is also involved in tendon and ligament formation and repair. In addition, GDF7 regulates bone formation, mesenchymal stem cell differentiation, neuronal differentiation, and axon guidance.

Uromodulin (Tamm–Horsfall protein) is produced mainly by cells in the kidney’s thick ascending limb and is the most abundant protein in normal urine.
Uromodulin takes part in salt and water regulation, helps prevent urinary tract infections and kidney stones, and influences inflammation and immune activity in the kidney.
Reduced Uromodulin levels is associated with chronic kidney disease.
UMOD mutations causes unproper protein folding and thus transported incorrectly, resulting in its accumulation inside kidney tubular cells that damages the tubules and cause kidney disease (ADTKD-UMOD), associated with high uric acid, gout, and progressive kidney failure.

Eukaryotic translation initiation factor 3 subunit J (EIF3J) is a member of the EIF-3 subunit J family. EIF3 has a crucial role in binding of initiator methionyl-tRNA and mRNA to the 40S ribosomal subunit to produce the 40S initiation complex. EIF3J binds to the aminoacyl (A) site and mRNA access channel of the 40S subunit, setting EIF3J directly in the ribosomal decoding center. In addition, EIF3J interacts with eIF1A and reduces 40S subunit affinity for mRNA. An elevated affinity for mRNA is restored upon enlistment of initiator tRNA, despite the fact EIF3J remains in the mRNA-binding cleft in the presence of tRNA.

EIF4EBP2 belongs to the eukaryotic translation initiation factor 4E binding protein family. Even though EIF4EBP2 protein binds eIF4E and inhibits translation initiation, growth factors can release this inhibition by a phosphorylation-dependent disruption. EIF4EBP2 mediates the regulation of protein translation by hormones, growth factors and other stimuli that signal through the MAP kinase pathway. Regulation of this protein is associated to cell proliferation, cell differentiation and viral infection.

Mitochondrial Ribosome Recycling Factor (MRRF) is a member of the RRF family. MRRF attaches to the large ribosomal subunit in the cleft which has a peptidyl transferase center. MRRF controls the release of ribosome from messenger RNA at the termination of protein biosynthesis. Also, it may intensify the efficacy of translation by recycling ribosome from one round of translation to another.

Basic fibroblast growth factor 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. This protein functions as a modifier of endothelial cell migration and proliferation, as well as an angiogenic factor. It acts as a mitogen for a variety of mesoderm- and neuroectoderm-derived cells in vitro, thus is thought to be involved in organogenesis. Three alternatively spliced variants encoding different isoforms have been described. The heparin-binding growth factors are angiogenic agents in vivo and are potent mitogens for a variety of cell types in vitro. There are differences in the tissue distribution and concentration of these 2 growth factors.

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.

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.

Eukaryotic Translation Initiation Factor 4E-Binding Protein 3 (EIF4EBP3) belongs to the EIF4EBP family whose proteins bind to eukaryotic initiation factor 4E and regulate its assembly into EIF4F, the multi-subunit translation initiation factor that identifies the mRNA cap structure.

ST6GAL1 also known as ST6 Beta-Galactosamide Alpha-2,6-Sialyltranferase 1, is part of the glycosyltransferase family 29. ST6GAL1 is a type II membrane protein which catalyzes the transfer of sialic acid from CMP-sialic acid to galactose-containing substrates. Furthermore, ST6GAL1 is normally found in the Golgi however it can be proteolytically processed to a soluble form, ST6GAL1 is also involved in the generation of the cell-surface carbohydrate determinants as well differentiation antigens HB-6, CD75, and CD76.

EIF1B is critical for the scanning process in vitro. EIF1B is an element of a complex involved in recognition of the initiator codon during the scanning process. Translation is also initiated by the function of EIF1B in regulating the activity of ribosomal subunits 43S, 48S and 40S. EIF1B enables 43S ribosomal complexes to distinguish between cognate and near-cognate initiation codons, perceiving the nucleotide content of initiation codons.

PLAUR is one of 2 activators which convert the extracellular zymogen plasminogen to plasmin, a serine protease involved in a various normal and pathological processes that require cell migration and/or tissue destruction. PLAUR protein is synthesized and released from cells as a single-chain proenzyme with narrow enzymatic activity and is converted to an active two-chain disulfide-linked active enzyme by plasmin and other specific proteinases.