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SDF-1 (stromal cell-derived factor-1) is small cytokine belonging to the chemokine family that is officially designated Chemokine (C-X-C motif) ligand 12 (CXCL12). It is produced in two forms, SDF-1?/CXCL12a and SDF-1?/CXCL12b, by alternate splicing of the same gene. Chemokines are characterized by the presence of four conserved cysteines, which form two disulfide bonds. The CXCL12 proteins belong to the group of CXC chemokines, whose initial pair of cysteines are separated by one intervening amino acid. CXCL12 is strongly chemotactic for lymphocytes and has been implicated as an important cell co-ordinator during development. During embryogenesis it directs the migration of hematopoietic cells from foetal liver to bone marrow. Mice which were knocked-out for CXCL12 gene were lethal before the birth or within just 1 hour of life. As another role, CXCL12a alters also the electrophysiology of neurons. CXCL12 was shown to be expressend in many tissues in mice (including brain, thymus, heart, lung, liver, kidney, spleen and bone marrow).
The receptor for this chemokine is CXCR4, which was previously called fusin. This CXCL12-CXCR4 interaction used to be considered exclusive (unlike for other chemokines and their receptors), but recently it was suggested that CXCL12 is also bound by CXCR7 receptor.
The gene for CXCL12 is located on human chromosome 10. In human and mouse both CXCL12 and CXCR4 show high identity of sequence: 99% and 90%, respectively.

Syntaxin 4 (STX4) is a member of the syntaxin/epimorphin family of proteins. The Syntaxin family is cellular receptors for transport vesicles which participate in exocytosis in neutrophils. Syntaxin 4 is vital for normal regulation of glucose metabolism uptake in skeletal muscle and decline in STX4 protein levels lead to reduction of whole-body hormone-stimulated glucose metabolism. STX4 is expressed in neutrophils and neutrophil-differentiated HL-60 cells. The STX4 expression in neutrophils increases with differentiation.

SDF-1 (stromal cell-derived factor-1) is small cytokine belonging to the chemokine family that is officially designated Chemokine (C-X-C motif) ligand 12 (CXCL12). It is produced in two forms, SDF-1?/CXCL12a and SDF-1?/CXCL12b, by alternate splicing of the same gene. Chemokines are characterized by the presence of four conserved cysteines, which form two disulfide bonds. The CXCL12 proteins belong to the group of CXC chemokines, whose initial pair of cysteines are separated by one intervening amino acid. CXCL12 is strongly chemotactic for lymphocytes and has been implicated as an important cell co-ordinator during development. During embryogenesis it directs the migration of hematopoietic cells from foetal liver to bone marrow. Mice which were knocked-out for CXCL12 gene were lethal before the birth or within just 1 hour of life. As another role, CXCL12a alters also the electrophysiology of neurons. CXCL12 was shown to be expressend in many tissues in mice (including brain, thymus, heart, lung, liver, kidney, spleen and bone marrow).
The receptor for this chemokine is CXCR4, which was previously called fusin. This CXCL12-CXCR4 interaction used to be considered exclusive (unlike for other chemokines and their receptors), but recently it was suggested that CXCL12 is also bound by CXCR7 receptor.
The gene for CXCL12 is located on human chromosome 10. In human and mouse both CXCL12 and CXCR4 show high identity of sequence: 99% and 90%, respectively.

DHH is part of the Hedgehog family which encodes signaling molecules that are involved in regulating morphogenesis. DHH protein is a precursor that is autocatalytically cleaved, the N-terminal portion is soluble and contains the signalling activity while the C-terminal portion is involved in precursor processing. Additionally, the C-terminal product covalently attaches a cholesterol moiety to the N-terminal product, restricting the N-terminal product to the cell surface and preventing it from freely diffusing throughout the organism. Defects in DHH protein have been associated with partial gonadal dysgenesis (PGD) accompanied by minifascicular polyneuropathy. DHH plays a role both male gonadal differentiation and perineurial development.
DHH plays a role in intercellular signaling which is essential for a variety of patterning events during development. DHH functions as a spermatocyte survival factor in the testes & is essential for testes development.

Interleukin-1 ra is a member of the interleukin 1 cytokine family. This protein inhibits the activities of interleukin 1, alpha (IL1A) and interleukin 1, beta (IL1B), and modulates a variety of interleukin 1 related immune and inflammatory responses. This gene and five other closely related cytokine genes form a gene cluster spanning approximately 400 kb on chromosome 2. A polymorphism of this gene is reported to be associated with increased risk of osteoporotic fractures and gastric cancer. Four alternatively spliced transcript variants encoding distinct isoforms have been reported.

S100P was originally described as a placental protein of 95 amino acid residues shares about 50% sequence identity with the brain S100 proteins alpha and beta.
S100 proteins are small dimeric members of the EF-hand superfamily of Ca(2+) binding proteins thought to participate in mediating intracellular Ca(2+) signals by binding to and thereby regulating target proteins in a Ca(2+)-dependent manner. S100P in addition to binding Ca2+, also binds Zn2+ and Mg2+. S100P gene is located on chromosome 4p16.
S100P is dysregulated in the androgen-independent prostate cancer cell lines LNCaP-R, DU145, and PC3 and may play a role in the etiology of prostate cancer.
In ductal hyperplasias, in situ and invasive ductal carcinoma, but not in the normal tissues, S100P overexpression is an early event that might play an important role in the immortalization of human breast epithelial cells in vitro and tumor progression in vivo.
In NIH3T3 cells, the expression of S100P led to the presence of S100P in the culture medium, increased cellular proliferation, and enhanced survival following detachment from the culture substrate or after exposure to the chemotherapeutic agent 5-flurouracil. The proliferation and survival effects of S100P expression were duplicated in a time- and concentration-dependent manner by extracellular addition of purified S100P to wild-type NIH3T3 cells and correlated with the activation of Erks and NFB.
To determine the mechanisms involved in these effects, we tested the hypothesis that S100P activated RAGE (Receptor for Activated Glycation End-Products). It was found that S100P coimmunoprecipitated with RAGE. Furthermore, the effects of S100P on cell signaling, proliferation and survival were blocked by agents that interfere with RAGE including administration of an amphoterin derived peptide known to antagonize RAGE activation, anti-RAGE antibodies and by expression of a dominant negative RAGE. These data suggest that S100P can act in an autocrine manner via RAGE to stimulate cell proliferation and survival.

CD276, belongs to the B7 family of immunoregulatory transmembrane glycoproteins expressed by T cells. CD276 is a costimulatory molecule for T cell activation in addition to IFN-gamma production. Furthermore, CD276 upregulates BRCC3 expression, preventing DNA defects caused by 5-Fu. CD276 is correlated with TNM stage of NSCLC and act as a potential biomarker for NSCLC-derived MPEs. CD276 inhibits natural-killer mediated cell lysis in tumor cells, and act as a marker for detection of neuroblastoma cells. CD276 is implicated in the development of acute as well as chronic transplant rejection and in the regulation of lymphocytic activity at mucosal surfaces. In addition, CD276 provides the placenta & fetus a proper immunological environment during the course of pregnancy.

Interleukin-18 receptor accessory protein (IL18RAP), belongs to the IL-1 family of cytokines which holds multiple immunoregulatory functions. It has been found that IL18RAP does not mediate IL18-binding, however, IL18RAP is involved in IL18-dependent signal transduction, which leads to NF-kappa-B and JNK activation. IL18R1 as well as IL18RAP polymorphisms have been linked with the following diseases: schizophrenia, HSV1 seropositivity and atopic asthma.

TIE-1 (tyrosine kinase with Ig and EGF homology domains 1) and TIE-2/Tek comprise a receptor tyrosine kinase (RTK) subfamily with unique structural characteristics: two immunoglobulin-like domains flanking three epidermal growth factor (EGF)-like domains and followed by three fibronectin type III-like repeats in the extracellular region and a split tyrosine kinase domain in the cytoplasmic region. These receptors are expressed primarily on endothelial and hematopoietic progenitor cells and play critical roles in angiogenesis, vasculogenesis and hematopoiesis. Human TIE-1 cDNA encodes a 1122 amino acid (aa) residue precursor protein with an 18 residue putative signal peptide, a 726 residue extracellular domain and a 353 residue cytoplasmic domain. Two ligands, angiopoietin-1 (Ang1) and angiopoietin-2 (Ang2), which bind TIE-2 with high-affinity have been identified. Ang2 has been reported to act as an antagonist for Ang1. Mice engineered to overexpress Ang2 or to lack Ang1 or Tie-1 display similar angiogenic defects.

Activating transcription factor 4 (ATF4) is a member of a family of DNA-binding proteins which includes the AP-1 family of transcription factors, cAMP-response element binding proteins and CREB-like proteins. The ATF4 gene encodes a transcription factor which was initially identified as a widely expressed mammalian DNA binding protein that could bind a tax-responsive enhancer element in the LTR of HTLV-1.

CD226 belongs to the Ig-superfamily containing 2 Ig-like domains of the V-set. CD226 is a 65kDa glycoprotein expressed on the surface NK cells, platelets, monocytes and a subset of T cells. CD226 facilitates cellular adhesion of platelets and megakaryocytic cells to vascular endothelial cells. CD226 also plays a role in megakaryocytic cell maturation.

EIF4E is part of the eukaryotic initiation factor 4 families, controls translation of maternal mRNAs in early embryos before the onset of zygotic transcription. EIF4E identifies and binds to the 7 methyl GTP cap structure of eukaryotic mRNAs, thus modulates the initiation of translation. EIF4E enables ribosome binding by inducing the unwinding of the mRNAs secondary structures.

The 14-3-3 family of proteins plays a key regulatory role in signal transduction, checkpoint control, apoptotic and nutrient-sensing pathways. 14-3-3 proteins are highly conserved and ubiquitously expressed. There are at least seven isoforms that have been identified in mammals. The 14-3-3gamma, a subtype of the 14-3-3 family of proteins, was thought to be brain and neuron-specific. It has been shown to interact with RAF1 and protein kinase C, proteins involved in various signal transduction pathways.

CD44 is a cell-surface glycoprotein that plays a role in cell-cell interactions, cell adhesion and migration. CD44 is a receptor for hyaluronic acid and also interacts with other ligands, such as osteopontin, collagens, and matrix metalloproteinases. CD44 participates in a wide variety of cellular functions such as lymphocyte activation, recirculation and homing, hematopoiesis, and tumor metastasis.
CD44 and CD49d are putative activity markers and CD44 a potential novel therapeutic target in multiple sclerosis. Increased CD44 antigen is associated with relapses in non-small cell lung cancers.

MAX protein is part of the basic helix-loop-helix leucine zipper (bHLHZ) family of transcription factors. MAX forms homodimers and heterodimers with Mad, Mxi1 and Myc. Myc is an oncoprotein implicated in cell proliferation, differentiation and apoptosis. The homodimers and heterodimers compete for a common DNA target site (the E box) and rearrangement among these dimer forms offers a complex system of transcriptional regulation. In contrast to Myc, which is exceedingly regulated throughout progression during the cell cycle, Max is very stable and is much more abundant than Myc.

Streptavidin is a tetrameric protein secreted by Streptomyces avidinii which binds firmly to biotin. Streptavidin is widely used in molecular biology through its unique high affinity for the vitamin biotin. The dissociation constant (Kd) of the biotin-streptavidin complex is about ~10-15 mol/L. The strong affinity recognition of biotin and biotinylated molecules has made streptavidin one of the most important components in diagnostics and laboratory kits. The streptavidin/biotin system has one of the biggest free energies of association of yet observed for noncovalent binding of a protein and small ligand in aqueous solution (K_assoc = 10**14). The complexes are also extremely stable over a wide range of temperature and pH.

Osteoprotegerin acts as decoy receptor for rankl and thereby neutralizes its function in osteoclastogenesis. OPG inhibits the activation of osteoclasts and promotes osteoclast apoptosis in vitro. Bone homeostasis seems to depend on the local rankl/opg ratio. Osteoprotegerin may also play a role in preventing arterial calcification. May act as decoy receptor for trail and protect against apoptosis. Trail binding blocks the inhibition of osteoclastogenesis.

Calcium-binding protein 39-like (CAB39L), is analogous to MO25 and located in the serum of virtually half of all patients diagnosed with acute monocytic leukemia. CAB39L plays a role in carcinogenesis. Furthermore, LKB1 activity raises upon the binding of a regulatory complex consisting of the STE20-related adaptor-alpha (STRAD alpha) pseudo kinase and the CAB39L.

Elongin B (Elob) is a subunit of the transcription factor B (SIII) complex. SIII complex is a general transcription elongation factor that increases the RNA polymerase II transcription elongation past template-encoded arresting sites. The SIII complex comprised of a transcriptionally active subunit (A) and 2 regulatory subunits (B and C). Subunit A is transcriptionally active and its transcription activity is enhanced by binding to the dimeric complex of the SIII regulatory subunits B and C. The von Hippel-Lindau tumor suppressor protein binds to elongin B and C and inhibits transcription elongation.

Ubiquitin-conjugating enzyme E2 R2 (UBE2R2) is a member of the ubiquitin-conjugating enzyme family. Protein kinase CK2 is a ubiquitous and pleiotropic Ser/Thr protein kinase implicated in cell growth andtransformation. This protein is a protein similar to the E2 ubiquitin conjugating enzyme UBC3/CDC34. Studies propose that CK2-dependent phosphorylation of this ubiquitin-conjugating enzyme functions by regulating beta-TrCP substrate recognition and induces its interaction with beta-TrCP, enhancing beta-catenin degradation. UBE2R2 receives ubiquitin from the E1 complex and catalyzes its covalent attachment to other proteins. In vitro catalyzes monoubiquitination and 'Lys-48'-linked polyubiquitination. UBE2R2 may be implicated in degradation of katenin. Among the diseases associated with UBE2R2 are cblc, and herpes simplex.

The Defensin family are highly similar in their protein sequence and are microbicidal & cytotoxic peptides made by neutrophils. Beta Defensin-1 is an antimicrobial peptide having the resistance of epithelial surfaces to microbial colonization. Beta Defensin-1 has close proximity to Defensin Alpha-1 and has been implicated in the pathogenesis of cystic fibrosis.
Skin of patients having atopic dermatitis patients and mycosis fungoides (non-lesional and lesional) show lower human Beta Defensin-1 mRNA expression and higher human Beta Defensin-2 and human Beta Defensin-3 mRNA expression.
Beta Defensin is highly expressed by epithelial cells.
Beta-defensin 1 may play a role in the pathogenesis of severe sepsis.

STK11, which controls cell polarity and functions as a tumour suppressor, belongs to the serine/threonine kinase family. Mutations in this gene have been linked to Peutz-Jeghers syndrome- an autosomal dominant disorder. It is characterized by the growth of polyps in the gastrointestinal tract, pigmented macules on the skin and mouth, and other neoplasms.

P-Selectin also called Platelet Alpha-Granule Membrane Protein, CD62, and Granulocyte Membrane Protein GRMP belongs to a family of divalent cation-dependent carbohydrate-binding glycoproteins or adhesion molecules. Pselectin is expressed transiently on the surface of activated platelets and endothelial cells. P-Selectin is a 140 kDa protein which is stored in the alpha-granules of platelets and Weibel-Palade bodies of endothelial cells. Secreted P-selectin is thought to play a key role in the adhesion of platelets to monocytes and neutrophils during an inflammatory response. P-Selectin is a calcium-dependent receptor that binds to sialylated forms of Lewis blood group carbohydrate antigens on neutrophils and monocytes. Levels of P-Selectin may be elevated in a number of pathological conditions.