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UBL3 - a member of the ubiquitin-like family is found in the membrane. UBL3 holds two N-glycosylation sites, a C-terminal prenylation site and a protein kinase C phosphorylation site. Even though Ubiquitin-like proteins are not directly involved in protein degradation, it seems they have several mechanistic similarities to the ubiquitin pathway.

Glycylpeptide N-tetradecan-oyltransferases 2 (NMT2) is a cytoplasmic protein which is a member of the NMT family of proteins. The proteins in the NMT family catalyze the addition of a myristoyl group to the N-terminal glycine residue of eukaryotic, fungal and viral proteins. These proteins are mostly detected in the heart, gut, kidney, liver and placenta. NMT catalyzes the reaction of N-terminal myristoylation of various signaling proteins. NMT transfers myristic acid from myristoyl coenzyme A to the amino group of a protein's N-terminal glycine residue. There are several distinct NMTs which vary in the molecular weight and /or subcellular distribution.

Malignant T cell amplified sequence 1 (MCTS1) is an Anti-oncogene which takes part in cell cycle regulation by means of decreasing cell doubling time and encouraging-dependent growth and also by shorting the duration of G1 transit time and G1/S transition. MCTS1 also plays a role as translation enhancer. MCTS1 recruits the density-regulated protein/DENR and binds to the cap complex of the 5'-terminus of mRNAs, thereupon altering the mRNA translation profile; Up-regulates protein levels of BCL2L2, TFDP1, MRE11A, CCND1 and E2F1, while mRNA levels remains constant.

A 16-kDa peptide hormone secreted from white adipocytes and implicated in the regulation of food intake and energy balance. Leptin provides the key afferent signal from fat cells in the feedback system that controls body fat stores.

CKMT1A is in charge of the transfer of high energy phosphate from mitochondria to the cytosolic carrier, creatine. CKMT1A is a member of the creatine kinase isoenzyme family and exists as two isoenzymes, sarcomeric MtCK and ubiquitous MtCK, encoded by separate genes. Mitochondrial creatine kinase arises in two different oligomeric forms: dimers and octamers, unlike the exclusively dimeric cytosolic creatine kinase isoenzymes. Numerous malignant cancers with poor prognosis have displayed overexpression of ubiquitous mitochondrial creatine kinase which is linked to high energy turnover and inability to remove cancer cells through apoptosis.

FKBP4 is part of the immunophilin protein family, which takes part in immunoregulation and necessary cellular processes concerning protein folding and trafficking. FKBP4 is a cis-trans prolyl isomerase that connects to the immunosuppressants FK506 and rapamycin. FKBP4 has high structural and functional similarity to FKBP1A, though, FKBP4 does not have immunosuppressant activity when complexed with FK506. FKBP4 is known to connect with phytanoyl-CoA alpha-hydroxylase. FKBP4 associates with HSP90 & HSP70 thus takes part in the intracellular trafficking of hetero-oligomeric forms of the steroid hormone receptors. FKBP4 highly associates with adeno-associated virus type 2 vectors (AAV) resulting in a considerable increase in AAV-mediated transgene expression in human cell lines. FKBP4 is involved in the optimal use of AAV vectors in human gene therapy.

Insulin Receptor (INSR) is a receptor tyrosine kinase which mediates the pleiotropic actions of insulin. Binding of insulin to the insulin receptor (INSR) stimulates glucose uptake. Once the precursor signal peptide is removed, the insulin receptor precursor is post-translationally cleaved into 2 chains (alpha and beta) which are covalently linked. Insulin binding initiates phosphorylation of several intracellular substrates, including, insulin receptor substrates (IRS1, 2, 3, 4), SHC, GAB1, CBL and other signaling intermediates. Each of these phosphorylated proteins function as docking proteins for other signaling proteins which contain Src-homology-2 domains (SH2 domain) that specifically recognize different phosphotyrosines residues, including the p85 regulatory subunit of PI3K and SHP2.

Trypsin inhibitor SPINK1 is secreted from pancreatic acinar cells into pancreatic fluid. SPINK1 has a role in inhibition of trypsin-catalyzed premature initiation of zymogens in the pancreas and the pancreatic duct. Alterations in SPINK1 gene are the cause for tropical calcific and pancreatitis hereditary pancreatitis.

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.

UBE2D2 belongs to the E2 ubiquitin-conjugating enzyme family. UBE2D2 takes part in the ubiquitination of the tumor-suppressor protein p53, which is induced by an E3 ubiquitin-protein ligase. UBE2D2 catalyzes ubiquitination of IkB-alpha in a SCFB-TRCP and phosphorylation dependent method.

Vascular endothelial growth factor (VEGF) is an important signaling protein involved in vessel formation 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/macrophage migration, neurons, cancer cells, kidney epithelial cells ). VEGF mediates increased vascular permeability, induces vasculogenesis and endothelial cell production, promotes cell migration, and inhibits apoptosis. In vitro, VEGF has been shown to stimulate endothelial cell mitogenesis and cell migration. VEGF is also a vasodilator and increases microvascular permeability and was originally referred to as vascular permeability factor. VEGF is located in normal cartilage though only osteoarthritic cartilage expresses the VEGF receptors, NP1, VEGFR1 and VEGFR2. The VEGF level in the culture media from OA chondrocytes was more than 3 folds higher than in media from normal chondrocytes

Chemokine (C-X-C motif) ligand 1 (CXCL1) is a small cytokine belonging to the CXC chemokine family that was previously called GRO1 oncogene, Neutrophil-activating protein 3 (NAP-3) and melanoma growth stimulating activity, alpha (MSGA-a). It is secreted by human melanoma cells, has mitogenic properties and is implicated in melanoma pathogenesis. CXCL1 is expressed by macrophages, neutrophils and epithelial cells, and has neutrophil chemoattractant activity. CXCL1 plays a role in spinal cord development by inhibiting the migration of oligodendrocyte precursors and is involved in the processes of angiogenesis, inflammation, wound healing, and tumorigenesis. This chemokine elicits its effects by signaling through the chemokine receptor CXCR2. The gene for CXCL1 is located on human chromosome 4 amongst genes for other CXC chemokines.

ANXA5 is a member of the annexin family of calcium-dependent phospholipid binding proteins which are involved in membrane-related activity along exocytotic and endocytotic pathways. ANXA5 is a phospholipase A2 and protein kinase C inhibitory protein with calcium channel properties and takes part in cellular signal transduction, inflammation, growth and differentiation. ANXA5 is an anticoagulant protein that acts as an indirect inhibitor of the thromboplastin-specific complex, which is involved in the blood coagulation cascade. ANXA5 regulates coagulability in the blood stream by binding to phosphatidylserine and sulfatide. ANXA5 protects sinsuoidal endothelial cells from ischemia reperfusion damage. ANXA5 is necessary for normal CFTR chloride channel activity.

Fibroblast growth factor 18 (FGF18) is a member of the large FGF family which has at least 23 members. FGF18 is a binding growth factor with a core 120 amino acid FGF domain which allows for a common tertiary structure. FGFs are expressed in the course of the embryonic development and in restricted adult tissues. FGF-18 is an indispensable regulator of long bone and calvarial development. FGF-18 signals via FGFR 1c, 2c, 3c, and 4.

E-cadherin (uvomorulin, cell-CAM120/80) is a calcium dependent cell adhesion molecule expressed predominately in epithelial tissues. It plays an important role in the growth and development of cells via the mechanisms of control of tissue architecture and the maintenance of tissue integrity. Numerous studies have demonstrated that reduction and/or loss of Ecadherin expression in carcinomas correlates positively with the potential of these tumors for invasion and metastasis.

The hematopoietic growth factor GM-CSF or granulocyte macrophage colony-stimulating factor, stimulates the development of neutrophils & macrophages, enhance proliferation and development of early erythroid megakaryocytic & eosinophilic progenitor cells. GM-CSF is secreted from the fibroblasts, monocytes, T-lymphocytes & endothelial cells. This protein blocks the migration of neutrophils & induces the biological activity of mature end-cells.

Glia Maturation Factor-Beta (GMF-Beta) is a 17 kDa protein nerve gorwth factor identified as a growth and differentiation factor in the vertebrate brain.

Glia Maturation Factor-Beta stimulates differentiation of normal neurons as well as glial cells. GMFB inhibits the proliferation of the N-18 neuroblastoma line and the C6 glioma line while promoting their phenotypic expression.
GMF-beta inhances the phenotypic expression of glia & neurons thus inhibits the proliferation of their respective tumors when added to cell culture. Although astrocytes produce GMF-b and stores it inside the cells, they don’t secrete the GMF-B into the cultured medium. Cell- surface GMFb acts on the target cells at close range when cells are in direct contact. GMF-Beta is produced by thymic epithelial cells and plays an important role in T cell development in favor of CD4+ T cells.
GMF-Beta is a brain-specific protein which belongs to the actin-binding proteins (ADF) family. GMF-beta appears to play a role in the differentiation, maintenance, and regeneration of the nervous system. It also supports the progression of certain auto-immune diseases, possibly through its ability to induce the production and secretion of various pro-inflammatory cytokines.

MBP is a major component of the myelin sheath of oligodendrocytes and Schwann cells in the nervous system, although, MBP-related transcripts are also present in the bone marrow and the immune system. These mRNAs emerge from the long MBP gene which holds three additional exons located upstream of the classic MBP exons. The Golli mRNAs contain three exons unique to Golli-MBP, spliced in-frame to one or more MBP exons. The second family of transcripts contains only MBP exons and produces the well characterized myelin basic proteins. MBP transcription unit is an essential part of the Golli transcription unit and the arrangement is important for the function and/or regulation of these genes.

PA2G4 belongs to the peptidase M24C family and functions as an RNA-binding protein involved in cellular proliferation and differentiation processes. PA2G4 is a component of pre-ribosomal ribonucleoprotein complexes, participating in ribosome assembly and regulating the later steps of rRNA processing. Also, PA2G4 interacts with ErbB-3 and may function as a modulator of the ErbB-3 mediated signal transduction pathway by regulating the effects of Neuregulin-1. Furthermore, PA2G4 is a transcriptional co-repressor of androgen receptor-regulated genes and other cell cycle regulatory genes through its interactions with histone deacetylases. PA2G4 is implicated in growth inhibition and the induction of differentiation of human cancer cells. In addition, PA2G4 mediates cap-independent translation of specific viral IRESs (internal ribosomal entry site). PA2G4 associates with 28S, 18S and 5.8S mature rRNAs, several rRNA precursors and probably U3 small nucleolar RNA.

IVD is a mitochondrial matrix enzyme that is part of the cyl-CoA dehydrogenase family which catalyzes the third step in leucine catabolism. The genetic deficiency of IVD leads to a buildup of isovaleric acid, which is toxic to the central nervous system and results in isovaleric acidemia. IVD is a homotetrameric flavoenzyme which catalyzes the conversion of isovaleryl-CoA to 3-methylcrotonyl-CoA.

DENR takes part in the translation of target mRNAs by scanning and recognizing the initiation codon. DENR protein is involved in the intonation of the translational profile of a subset of cancer-related mRNAs when engaged to the translational initiation complex by the oncogene MCTS1.

Transforming Growth Factor-Alpha (TGF-alpha) belongs to the EGF family of cytokines. TGFA soluble form is discharged from the membrane by proteolytic cleavage. Membrane-bound proTGF-alpha is biologically active and has a role in cell-cell adhesion or in the stimulation of adjacent cells. TGFA expression is common in transformed cells. Additionally, TGFA is expressed in normal tissues during embryogenesis and in adult cells/tissues, including the pituitary, keratinocytes, and macrophages.

ANGPTL3 and ANGPTL4 are angiopoietin-like proteins secreted and expressed mainly by the liver, their role being the regulation of triglyceride metabolism by inhibiting the lipolysis of triglyceride-rich lipoproteins. During different nutritional states (feeding/fasting) the levels of the circulating triglycerides are regulated by Angptl3 and Angptl4 through differential inhibition of Lipoprotein lipase (LPL) as shown by the experimental data. The molecular structure of ANGPTL3 is similar to that of the angiopoietins (vascular endothelial growth factors). Deletion mutants of human Angiopoietin 5 were used in order to demonstrate that the N-terminal domain (fragment 17-207) and not the C-terminal fibrinogen-like domain (fragment 207-460) increased the plasma triglyceride levels in mice.