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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.

CD8B encodes the CD8 beta chain isoforms of the CD8 antigen. CD8 is a cell surface glycoprotein which facilitates efficient cell-cell interactions within the immune system and is located on most cytotoxic T lymphocytes. The T-cell receptor on the T lymphocyte and the co-receptor CD8 antigen identify antigens exposed by an antigen presenting cell (APC) in the context of class I MHC molecules. The functional co-receptor is either a heterodimer composed of one alpha and one beta chain or a homodimer composed of two alpha chains. Both alpha and beta chains share substantial homology to immunoglobulin variable light chains.

Neuropilin 1 (Nrp1) is a transmembrane glycoprotein which functions as a co-receptor for several extracellular ligands including class III/IV semaphorins, some isoforms of vascular endothelial growth factor and transforming growth factor beta. Nrp1 binds vascular endothelial growth factor (VEGF)-A and is believed to serve as a coreceptor for kinase insert domain-containing receptor (KDR) by connecting with KDR and enhancing VEGF signaling. Nrp1 is a marker of regulatory T 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, HBEGF 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.

PLGF is a growth factor active in angiogenesis, and endothelial cell growth, stimulating their proliferation and migration. It binds to receptor vegfr-1/flt1.
PLGF-2 binds neuropilin-1 and 2 in a heparin-dependent manner.

IFN-gamma produced by lymphocytes activated by specific antigens or mitogens.
IFN-gamma, in addition to having antiviral activity, has important immunoregulatory functions, it is a potent activator of macrophages, and has antiproliferative effects on transformed cells and it can potentiate the antiviral and antitumor effects of the type I interferons.

BCL2 Like 10 (BCL2L10) is a member of the BCL-2 protein family. BCL2 family members form hetero or homodimers and serve as anti or pro-apoptotic regulators which are involved in a wide variety of cellular activities. BCL2L10 includes the conserved BH4, BH1 and BH2 domains. BCL2L10 interacts with other members of BCL2 protein family including BCL2, BCL2L1/BCL-X(L), and BAX. BCL2L10 overexpression suppresses cell apoptosis possibly through the prevention of cytochrome C release from the mitochondria, and consequently activating caspase-3 activation.

GFP, also known as Green Fluorescent Protein, is a protein produced by the jellyfish (Aequorea Victoria) that produces bioluminescence in the green zone of the noticeable spectrum. Green Fluorescent Protein is a useful and ubiquitous instrument for producing chimeric proteins, where it functions as a fluorescent protein tag. GFP is expressed in most known cell types and is used as a noninvasive fluorescent marker in living cells and organisms. Green Fluorescent Protein permits a broad range of applications where it has functioned as a cell lineage tracer, reporter of gene expression, or as a measure of protein-protein interactions. Enhanced GFP (eGFP) has F64L and S65T mutations, which make GFP show increased fluorescence and fold more efficiently under 370.

PDGF-BB is a member of the platelet-derived growth factor family. The four members of this family are mitogenic factors for cells of mesenchymal origin and are characterized by a motif of eight cysteines. This gene product can exist either as a homodimer (PDGF-BB) or as a heterodimer with the platelet-derived growth factor alpha polypeptide (PDGF-AB), where the dimers are connected by disulfide bonds. Mutations in this gene are associated with meningioma. Reciprocal translocations between chromosomes 22 and 7, at sites where this gene and that for COL1A1 are located, are associated with a particular type of skin tumor called dermatofibrosarcoma protuberans resulting from unregulated expression of growth factor. Two splice variants have been identified for this gene.

The FGFs are a family of more than 20 small (~17–26 kDa) secreted peptides. The initial characterization of these proteins focused on their ability to stimulate fibroblast proliferation. This mitogenic activity was mediated through FGF receptors (FGFRs) 1, 2, or 3. A fourth closely related tyrosine kinase receptor (FGFR4) was able to bind the FGFs but did not lead to a mitogenic response.
FGFs modulate cellular activity via at least 5 distinct subfamilies of high-affinity FGF receptors (FGFRs): FGFR-1, -2, -3, and -4, all with intrinsic tyrosine kinase activity and, except for FGFR-4, multiple splice isoforms, and FGFR-5, which lacks an intracellular kinase domain. There is growing evidence that FGFRs can be important for regulation of glucose and lipid homeostasis. The overexpression of a dominant negative form of FGFR-1 in ? cells leads to diabetes in mice, which thus implies that proper FGF signaling is required for normal ? cell function and glycemia maintenance. FGFR-2 appears to be a key molecule during pancreatic development. Moreover, FGFR-4 has been implicated in cholesterol metabolism and bile acid synthesis.
FGF-21 is preferentially expressed in liver, but an exact knowledge of FGF-21 bioactivity and its mode of action have been lacking to date. FGF-21 is a potent activator of glucose uptake on adipocytes, protects animals from diet-induced obesity when overexpressed in transgenic mice, and lowers blood glucose and triglyceride levels when therapeutically administered to diabetic rodents.

CD1B belongs to CD1 family of transmembrane glycoproteins, which are structurally associated with the MHC proteins and form heterodimers with the beta-2-microglobulin. CD1B includes one Ig-like domain. CD1B is an antigen-presenting protein which connects self and nonself lipid and glycolipid antigens and displays them to T-cell receptors on natural killer T-cells.

Neuregulin/Heregulin is a family of structurally related polypeptide growth factors which are stemmed from alternatively spliced genes (NRG1, NRG2, NRG3 and NRG4). Thus far, 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 act to induce the growth and differentiation of epithelial, neuronal, glial, and other types of cells.

PRSS3 is a trypsinogen, and a member of the trypsin family of serine proteases. PRSS3 is expressed in the pancreas and brain and is unaffected by common trypsin inhibitors. It is active on peptide linkages involving the carboxyl group of lysine or arginine. PRSS3 is restricted to the locus of T cell receptor beta variable orphans on chromosome 9. 4 different isoforms encoded by 4 transcript variants were identified for this gene.

The adipose tissue exclusively expresses and secretes Adiponectin (Acrp30). Acrp30 is involved in various physiological processes such as energy homeostasis, insulin sensitivity, hormonal processes, fatty acid metabolism and obesity.
Adiponectin circulates in the plasma. Decreased levels of Adiponectin are associated with insulin resistance and hyperinsulinemia, as seen in people with obesity insulin resistance, and diabetes type 2, whose plasma levels of adiponectin are reduced.
The modular structure of Acrp30 is comprised of N-terminal collagenous domain followed by a C-terminal globular domain.
Acrp30 also acts as a significant negative regulator in hematopoiesis and immune systems; it may be involved in ending inflammatory responses through its inhibitory functions. Adiponectin inhibits endothelial NF-kappa-b signaling through a cAMP-dependent pathway, it also inhibits TNF-alpha- induced expression of endothelial adhesion molecules.

IL17 is a proinflammatory cytokine produced by activated T cells. IL-17 regulates the activities of NF-kappaB and mitogen-activated protein kinases. Interleukin-17 can stimulate the expression of IL6 and cyclooxygenase-2 (PTGS2/COX-2), as well as enhance the production of nitric oxide (NO). High levels of IL-17 are associated with several chronic inflammatory diseases including rheumatoid arthritis, psoriasis and multiple sclerosis.

Prorelaxin H2 (RLN2) is a member of the insulin gene superfamily. This family which is produced by the ovary, targets the mammalian reproductive system to ripen the cervix, elongate the pubic symphysis and inhibit uterine contraction. It may also have other roles in boosting sperm motility, regulating blood pressure, controlling heart rate and releasing oxytocin and vasopressin. RLN2 is a peptide hormone linked to several therapeutically relevant physiological effects, including regulation of collagen metabolism and multiple vascular control pathways. The active form of the RLN2 protein consists of an A chain and a B chain linked by disulfide bonds.

FLT3 ligand is a receptor for the fl cytokine has a tyrosine-protein kinase activity & a growth factor that regulates proliferation of early hematopoietic cells. Flt3-Ligand synergizes with other CSFs and interleukins to induce growth and differentiation.

ADAM10 is part of the ADAM family which are cell surface proteins with a distinctive structure possessing both potential adhesion and protease domains. ADAM10 cleaves many proteins including TNF-alpha and E-cadherin. ADAM10 cleaves the membrane-bound precursor of tnf-alpha at 76- ala-|-val-77 to its mature soluble form. ADAM10 is in charge for the proteolytic release of several other cell-surface proteins, including heparin-binding epidermal growth-like factor, ephrin-a2 and for constitutive and regulated alpha-secretase cleavage of amyloid precursor protein ADAM10 is involved in the normal cleavage of the cellular prion protein. ADAM10 is involved in the cleavage of the adhesion molecule l1 at the cell surface and in the release of membrane vesicles, suggesting a vesicle-based protease activity. ADAM10 controls the proteolytic processing of notch and mediates lateral inhibition during neurogenesis.

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.

EPGN is an EGF-related polypeptide growth factor that signals through the ErbB receptor-1. EPGN is produced in numerous tissues, including the testis, liver, heart and in certain tumor cells. EPGN is mitogenic for fibroblasts and epithelial cells. Human EPGN is originally synthesized as a glycosylated 14.7 kDa transmembrane precursor protein, which is processed by proteolytic cleavage to produce a mature soluble sequence.

Bcl-XL is a transmembrane protein located in the mitochondrial membranes of cells that are long-lived and postmitotic, such as adult brain cells. It plays arole in the signal transduction pathway of the FAS-Ligand. Bcl-XL is an anti-apoptotic protein which is a member of the Bcl-2 family which are able to form heterodimers, and this is an significant event in the regulation of apoptosis. BCL-XL is involved in the survival of cancer cells.
Bcl-xL is the leading monitor of apoptosis/active cell suicide. Bcl-xL has cell death repressor activity and therefore acts as a survival protein.

CD4 is a cell-surface glycoprotein found on the mature helper T cells and immature thymocytes, as well as on monocytes and macrophages. (Some cytotoxic T cells have CD4 protein as well.) Normally, about 65% of T cells in the blood are CD4+ (have CD4 protein protruding from their membrane). A mature T cell with either have CD4 or CD8, but not both. During one stage of development T cells develop CD4 and CD8 receptors, but they eventually are differentiated in the thymus and become more specialized.

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.