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Lipopolysaccharide is a potent stimulator of monocytes and macrophages, causing secretion of tumor necrosis factor-alpha (TNF-alpha) and other inflammatory mediators. LITAF is a lipopolysaccharide-induced TNF-alpha factor, which is a DNA-binding protein and can mediate the TNF-alpha expression by direct binding to the promoter region of the TNF-alpha gene. The transcription of the LITAF gene is induced by tumor suppressor p53 and has been implicated in the p53-induced apoptotic pathway. Mutations in the LITAF gene cause Charcot-Marie-Tooth disease type 1C (CMT1C) and may be involved in the carcinogenesis of extramammary Paget''s disease (EMPD).

Kruppel-Like Factor 6 (KLF6) is a nuclear protein which has 3 zinc fingers. The zinc fingers of KLF6 are accountable for the specific DNA binding with the guanine-rich core promoter factors. The central region is involved in activation or posttranslational regulatory pathways, and the acidic N terminal domain takes part in the process of transcriptional activation.

Peroxisomal Biogenesis Factor 26 (PEX26) which is a part of the peroxin-26 gene family is probably required for protein import into peroxisomes. PEX26 attaches PEX1 and PEX6 to peroxisome membranes to form heteromeric AAA ATPase complexes needed for the import of proteins into peroxisomes. Deficiencies in this gene are the cause of peroxisome biogenesis disorder complementation group 8. PBD is a group of peroxisomal disorders evolving from a failure of protein import into the peroxisomal membrane or matrix.

Tumor necrosis factor is a cytokine involved in systemic inflammation and is a member of a group of cytokines that all stimulate the acute phase reaction. TNF is mainly secreted 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, INS resistance, and cancer.

The gene for TNFRSF12A was initially recognized as a fibroblast growth factor inducible immediate early response gene Fn14 in mouse NIH 3T3 fibroblasts. Human TNFRSF12A cDNA encodes a 129 amino acid residue type I transmembrane protein with a 27 aa signal peptide, a 53 aa extracellular domain, a 21 aa transmembrane domain and a 28 aa cytoplasmic domain. Human and mouse TNFRSF12A hold 82% aa sequence identity. TNFRSF12 is the tiniest member of the TNF receptor superfamily and has only one cysteine rich region in its extracellular domain. The TNFRSF12A cytoplasmic domain holds one TRAF binding motif which binds TRAFs 1, 2, and 3. TNFRSF12A binds its ligand TWEAK/TNFSF12A with high affinity to initiate a signal transduction cascade which subject to the cell type, causes different cellular responses such as cell death, cell proliferation, and angiogenesis.

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.

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.

Hypoxia-inducible factor-1 (HIF-1), identified as one of the transcription factors, has been found to play an essential role in cellular and systemic oxygen homeostasis. HIF-1 is a heterodimer composed of HIF-1b subunit and one of three subunits (Hif-1a, Hif-2 (or Hif-3)). The activation of Hif-1 (is closely associated with a variety of tumors and oncogenic pathways. Hif-1 (consists of DNA binding domain (DBD domain), Dimerization domain and C-terminal regulatory domains, including two transactivation domains (TAD), an oxygen-dependent degradation (ODD) domain, and inhibitory domains. Under hypoxic conditions HIF1A activates the transcription of more than 40 genes, including, erythropoietin, glucose transporters, glycolytic enzymes, VEGF, and other genes whose protein products increase oxygen delivery or facilitate metabolic adaptation to hypoxia. HIF-1A also plays a crucial role in embryonic vascularization, tumor angiogenesis and pathophysiology of ischemic disease. It binds to core DNA sequence 5'-[AG]CGTG-3' within the hypoxia response element (HRE) of target gene promoters. Activation involves recruitment of transcriptional coactivators such as CREBPB and EP300. Its activity is improved by interaction with both, NCOA1 or NCOA2. Interaction with redox regulatory protein APEX appears to activate CTAD and potentiates activation by NCOA1 and CREBBP. The induction is under reduced oxygen tension. HIF1A is also induced by a variety of receptor-mediated factors such as growth factors, cytokines, and circulatory factors for example PDGF, EGF, FGF-2, IGF-2, TGF-1 beta, HGF, TNF alpha, IL-1 beta, angiotensin-2 and thrombin. Nevertheless, this induction is less intense than that stimulated by hypoxia.

Intrinsic Factor is a member of the cobalamin transport protein family. It encodes a glycoprotein secreted by parietal cells of the gastric mucosa and is required for adequate absorption of vitamin B12 in the terminal ileum. Vitamin B12 is essential for erythrocyte maturation and mutations in the Intrinsic Factor may lead to congenital pernicious anemia. Upon entry into the stomach, vitamin B12 binds to one of two B12 binding proteins present in the gastric fluid. In the less acidic environment of the small intestine, these proteins dissociate from the vitamin, allowing it to bind to intrinsic factor and enter the portal circulation through a receptor in the ileal mucosa specific for the B12-intrinsic factor complex.

C1QTNF6 is a collagen type-IV specific for basement membranes. C1QTNF6 is vital for embryonic development.

TRAIL Receptor-1 (DR4) and TRAIL Receptor-2(DR5) are members of the TNFR superfamily of transmembrane proteins and contain a cytoplasmic "death domain", which is capable of activating the cell's apoptotic machinery. These receptors are activated by binding to either membrane anchored or soluble TRAIL/Apo2L.

KLF3 belongs to the Sp1-like/KLF family. KLFs is a family of evolutionarily conserved zinc finger-having transcription factors with various regulatory purposes in cell growth, embryogenesis, proliferation and differentiation. KLF3 is Kruppel-like zinc finger which contain transcription factors and take part in hematopoiesis.

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.

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.

Gametocyte Specific Factor 1 (GTSF1) is a member of the UPF0224 (FAM112) family and contains 1 CHHC-type zinc finger. A key paralog of the GTSF1 gene is GTSF1L.

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.

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.

Eukaryotic Translation Initiation Factor 3F, also known as EIF3F belongs to the eIF-3 subunit F family. EIF3F is a component of the eukaryotic translation initiation factor 3 (eIF-3) complex, which isessential for several steps in the initiation of protein synthesis. The eIF-3 complex associates with the 40S ribosomeand facilitates the recruitment of eIF-1, eIF-1A, eIF 2: GTP: methionyl-tRNAi and eIF-5 to form the 43S preinitiationcomplex (43S PIC). In addition, the eIF-3 complex stimulates mRNA recruitment to the 43S PIC and scanning of the mRNA forAUG recognition. The eIF-3 complex is also necessary for disassembly and recycling of post termination ribosomalcomplexes and subsequently prevents premature union of the 40S and 60S ribosomal subunits prior to initiation. Among the diseases associated with EIF3F are intrahepatic cholangiocarcinoma, and cholangiocarcinoma.

XIAP Associated Factor 1 (XAF1) is a protein which binds to and counteracts the inhibitory effect of a member of the IAP (inhibitor of apoptosis) protein family. IAP proteins bind to and inhibit caspases which are activated in the course of apoptosis. The ratio of IAPs and proteins which interfere with their activity, such as the XAF1 protein, influence the progress of the apoptosis signaling pathway. Additionally, XAF1 inhibits anti-caspase activity of BIRC4. XAF1 induces cleavage and inactivation of BIRC4 independent of caspase activation. Furthermore, XAF1 mediates TNF-alpha-induced apoptosis and is involved in apoptosis in trophoblast cells.

FGF-basic 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.

EIF1AX is an important eukaryotic translation initiation factor. EIF1AX is essential for the binding of the 43S complex (a 40S subunit, eIF2/GTP/Met-tRNAi and eIF3) to the 5'' end of capped RNA. EIF1AP1 is needed for maximal rate of protein biosynthesis. EIF1AX increases ribosome dissociation into subunits and stabilizes the binding of the initiator Met-tRNA (I) to 40 S ribosomal subunits.

PDGF-AA, PDGF-BB and PDGF-AB, are potent mitogens for a variety of cell types including smooth muscle cells, connective tissue cells, bone and cartilage cells, and some blood cells. The PDGF is stored in platelet alpha-granules and released upon platelet activation. The PDGF is involved in a number of biological processes, including hyperplasia, chemotaxis, embryonic neuron development, and respiratory tubule epithelial cell development. Two distinct signaling receptors used by PDGF
have been identified and named PDGFR-alpha and PDGFR-beta. PDGFR-alpha is high-affinity receptor for each of the three PDGF forms. On the other hand, PDGFR-beta interacts with only PDGF-BB and PDGF-AB.