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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.

PEDF is a noninhibitory serpin with neurotrophic, anti-angiogenic, and anti-tumorigenic properties. PEDF is a 50,000 dalton glycoprotein created and secreted in many tissues all the way through the body. A key component of the anti-angiogenic action of PEDF is the induction of apoptosis in proliferating endothelial cells. Additionally, PEDF is capable to inhibit the activity of angiogenic factors such as VEGF and FGF-2. The neuro-protective effects of PEDF are achieved through suppression of neuronal apoptosis induced by peroxide, glutamate, or other neurotoxins. The recognition of a lipase-linked cell membrane receptor for PEDF (PEDF-R) that binds to PEDF with high affinity should facilitate further elucidation of the underlying mechanisms of this pluripotent serpin. To date, PEDF-R is the only signaling receptor known to be used by a serpin family member. The unique range of PEDF activities associate it as a potential therapeutic agent for the treatment of vasculature related neurode

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.

Thrombopoietin is a glycoprotein hormone produced mainly by the liver and the kidney which regulates the production of platelets by the bone marrow. TPO stimulates the production as well as differentiation of megakaryocytes, the bone marrow cells which fragment into large numbers of platelets.

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.

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.
KIR2DL3 is an inhibitory Killer Cell Ig-like Receptor (KIR, previously called p58 KIR, cl-6, NKAT2 or KIR-K7), which recognizes class I MHC molecules (HLA-Cw1, -Cw3, -Cw7, and Cw8). KIR2DL3 inhibits the activity of NK cells thus preventing cell lysis.

Killer Cell Immunoglobulin-Like Receptor, 3 Domains Long Cytoplasmic Tail 2 (KIR3DL2) is a type 1 transmembrane protein of the p70 family of killer cell Ig-like receptors. KIR3DL2 is a receptor on NK cells for HLA-A alleles which Inhibits their activity consequently preventing cell lysis.

Pleiotrophin (Osteoblast-Specific Factor-1, OSF-1) contains 136 amino acid residues. The sequence is very rich in cationic amino acids (24% of the residues); lysine cluster sequences are found in the N-terminal and C-terminal ends of the structure.
The OSF-1 gene was shown by Northern blotting analysis to be expressed in mouse calvarial osteoblast-enriched cells and in mouse brain tissues, but not in thymus, spleen, kidney, liver, lung, testis or heart. Pleiotrophin has the ability to promote adhesion, migration, expansion, and differentiation of human osteoprogenitor cells. In addition to certain types of cancer, the embryonic growth and differentiation factor pleiotrophin is found also in adults in inflammatory diseases. In osteoarthritis, pleiotrophin is especially expressed in early stages, and its concentrations in the synovial fluid could serve as a marker for the progress of the disease. Pleitrophin might be involved in cartilage repair in osteoarthritis, in particular, in earlier stages.

Melanoregulin (MREG) takes part in membrane fusion and in regulating the biogenesis of disk membranes of photoreceptor rods. MREG is expressed in photoreceptor cells as two isoforms as a result of alternative splicing. MREG interacts with Peripherin-2, a photoreceptor specific tetraspanin protein which is required to preserve normal cell structure during the renewal process of membrane fusion. Moreover, MREG plays a part in the incorporation of pigments into hair.

SUB1 is a coactivator that functions together with TAFs and mediates functional interactions between upstream activators and the general transcriptional machinery. SUB1 interacts with the activation domain of transcription factor IIA (TFIIA) and TATA-binding protein (TBP)-associated factors (TAFs) to directly bind to double stranded DNA. SUB1 induces both activation and repression of RNAPII basal transcription, depending on the presence or absence of these transcription factors and holoenzyme components.

ASF1 Anti-Silencing Function 1 Homolog B (ASF1B) belongs to the H3/H4 family of histone chaperone proteins and is similar to the anti-silencing function-1 protein in yeast. ASF1B is the substrate of the tousled-like kinase family of cell cycle-regulated kinases, and may have a crucial role in modulating the nucleosome structure of chromatin by guaranteeing a regular supply of histones at sites of nucleosome assembly. ASF1B cooperates with CAF-1 (chromatin assembly factor 1) to stimulate replication-dependent chromatin assembly. ASF1B is highly expressed in the testis and at lower levels in colon, small intestine and thymus. ASF1B is necessary for spermatogenesis.

Immature Colon Carcinoma Transcript 1 (ICT1) functions as a codon-independent translation release factor that has lost all stop codon specificity and leads the termination of translation in mitochondrion in case of abortive elongation. The mature colon epithelium has 3 differentiated cell types which arise from a multipotent stem cell. ICT1 is involved in the hydrolysis of peptidyl-tRNAs which have been prematurely terminated and consequently in the recycling of stalled mitochondrial ribosomes. Digression from the normal maturation pathway by neoplastic transformation is assumed to originate in stem cells or their early descendants.

CD55 belongs to the RCA (regulators of complement activation) family characterized by 4-30 SCRs (short consensus repeats) in their plasma-exposed regions. CD55 is widely expressed in malignant tumors and nevertheless functions as an inhibitor of the complement system.

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.

Interleukin-7 is a potent lymphoid cell growth factor produced primarily by stromal cells.
IL-7 has been shown to support the proliferation and differentiation of pre B- and early T cells as well as displaying a biological effect on cells of NK and myeloid lineages.

ARF1 is a small guanine nucleotide-binding protein that increases the enzymatic activities of cholera toxin. ARF1 is necessary and ubiquitous in eukaryotes. ARF1 takes part in vesicular transport and functioning via phospholipase D activation. ARF1 is involved in membrane traffic and organelle integrity which are closely tied to their reversible association with membranes and distinct interactions with membrane phospholipids.

Interleukin-1b is produced by activated macrophages, IL-1B stimulates thymocyte proliferation by inducing il-2 release, b-cell maturation and proliferation, and fibroblast growth factor activity. IL1B proteins are involved in the inflammatory response, being identified as endogenous pyrogens, and are reported to stimulate the release of prostaglandin from synovial cells.

Active IL-12 is a p70 disulphide-linked dimer composed of p35 and p40 subunits. The protein is a pleiotropic cytokine produced primarily by antigen presenting cells and has multiple effects on T lymphocytes and natural killer cells in terms of stimulating cytotoxicity, proliferation, production of other cytokines and Th1 subset differentiation.

SERTA domain containing 2 (SERTAD2) takes part at E2F-responsive promoters to integrate signals which are given by PHD- and bromodomain-containing transcription factors. The SERTAD2 protein is taking part in modulating fat storage by down-regulating the expression of key genes which take part in thermogenesis, adipocyte lipolysis and oxidative metabolism.

Zinc Ribbon Domain Containing 1 (ZNRD1) is a protein which shows similarity to the Saccharomyces cerevisiae Rpa12p subunit of RNA polymerase I. ZNRD1 contains two potential zinc-binding motifs and takes part in regulation of cell proliferation. ZNRD1 is involved in cancer and human immunodeficiency virus progression. Alternate splicing of this gene results in two transcript variants encoding the same protein. Additional splice variants have been found, but their full-length sequences have not been determined.

Thrombin enzyme (Activated Factor IIa) is an important clotting promoter that controls the transformation of soluble fibrinogen to insoluble active fibrin strands. Thrombin is a coagulation protein and a serine protease (EC 3.4.21.5) that catalyzes many coagulation-related reactions. Thrombin triggers factor-XI, factor-V, Factor-XIII and factor-VIII. Thrombin endorses platelet activation, using activation of protease-activated receptors on the platelet. As a result of its high proteolytic specificity, thrombin has become an important biochemical protein. The thrombin cleavage site (Leu-Val-Pro-Arg-Gly-Ser) is widely used in linker regions of recombinant fusion protein constructs. After the purification of the fusion protein, thrombin is used to cleave between the Arginine and Glycine residues of the cleavage site, efficiently removing the purification tag from the protein of interest with a high degree of specificity.

Leukocyte Immunoglobulin Like Receptor B1 (LILRB1) is a member of the leukocyteimmunoglobulinlike receptor (LIR) family. LILRB1is expressed on immune cells, binds to MHC classI molecules on antigen-presenting cells and transduces a negative signal that inhibits stimulation of an immuneresponse. LILRB1 controls inflammatory responses and cytotoxicity to help focus the immune responseand limit autoreactivity. LILRB1 is also expressed on the surface of B cells and monocytes, subsets of NKcells, gamma δ T cells,memory/effector CD8+ T cells and monocyte-derived dendritic cells.