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CD68 encodes a 110-kD transmembrane glycoprotein that is highly expressed by human monocytes and tissue macrophages. It is a member of the lysosomal/endosomal-associated membrane glycoprotein (LAMP) family. The protein primarily localizes to lysosomes and endosomes with a smaller fraction circulating to the cell surface. It is a type I integral membrane protein with a heavily glycosylated extracellular domain and binds to tissue- and organ-specific lectins or selectins. The protein is also a member of the scavenger receptor family. Scavenger receptors typically function to clear cellular debris, promote phagocytosis, and mediate the recruitment and activation of macrophages. Alternative splicing results in multiple transcripts encoding different isoforms.

R-spondin-3 (RSPO3) belongs to the thrombospondin type 1 repeat supergene family. RSPO3 is a secreted protein which is widely expressed in many tissues. RSPO3 contains 2 Furin-like repeats which have been found in various eukaryotic proteins involved in the mechanism of signal transduction by receptor tyrosine kinases, and one TSP type-1 domain. RSPO3 acts as an activator of the beta-catenin signaling cascade, initiating TCF-dependent gene activation.

Macrophage Inflammatory Proteins (MIP) belong to the family of chemotactic cytokines known as chemokines. In humans, there are two major forms, MIP-1? and MIP-1? that are now officially named CCL3 and CCL4 respectively. Both are major factors produced by macrophages after they are stimulated with bacterial endotoxins. They activate human granulocytes (neutrophils, eosinophils and basophils) which can lead to acute neutrophilic inflammation. They also induce the synthesis and release of other pro-inflammatory cytokines such as interleukin 1 (IL-1), IL-6 and TNF-? from fibroblasts and macrophages. The genes for CCL3 and CCL4 are both located on human chromosome 17.

CTNNBIP1 binds CTNNB1 and avoids interaction between CTNNB1 and TCF (T-cell transcription factor) family members. CTNNBIP1 is a negative regulator of the Wnt signaling pathway.

Matrix Metallopeptidase 23B (MMP23B) belongs to the matrix metalloproteinase (MMP) family, and it is section of a duplicated region of chromosome 1p36.3. MMP23B is a protease. MMP23B regulates the surface expression of some potassium channels by holding them in the endoplasmic reticulum. Members of the matrix metalloproteinase (MMP) family are involved in the breakdown of extracellular matrix in normal physiological processes, such as embryonic development, reproduction, and tissue remodeling, as well as in disease processes, such as arthritis and metastasis.

PPIases catalyze the cis-trans isomerization of proline imidic peptide bonds in oligopeptides and accelerate the folding of proteins. Cyclophilin-A is a cyclosporin binding-protein and may play a role in cyclosporin A-mediated immunosuppression. Cyclophilin-A can also interact with several HIV proteins, including p55 gag, Vpr, and capsid protein, and has been shown to be necessary for the formation of infectious HIV virions. Multiple pseudogenes that map to different chromosomes have been reported.

CYP2E1, also known as Cytochrome P450 2E1 belongs to the cytochrome P450 mixed-function oxidase system which is involved in the metabolism of xenobiotics in the body. While CYP2E1 is implicated in the oxidative metabolism of small range substrates, commonly small polar molecules, there are many significant drug interactions which are mediated by CYP2E1.

Cytohesin-interacting protein, also known as CYTIP contains 2 leucine zipper domains as well as a putative C-terminal nuclear targeting signal. However, CYTIP does not contain any hydrophobic regions. In addition, CYTIP is expressed weakly in resting NK and T cells. It also modulates the activation of ARF genes by CYTH1.

Snail homolog 1 (SNAI1) is involved in induction of the epithelial to mesenchymal transition (EMT), formation and maintenance of embryonic mesoderm, growth arrest, survival and cell migration. SNAI1 binds to 3 E-boxes of the E-cadherin gene promoter and represses its transcription. The nuclear protein encoded by SNAI1 is structurally identical to the Drosophila snail protein, and is considered as well to be vital for mesoderm formation in the developing embryo. At least two variants of a similar processed pseudogene have been found on chromosome 2. Among the diseases associated with SNAI1 are waardenburg syndrome type iid, and inappropriate adh syndrome.

Prepronociceptin (PNOC) is the ligand of the opioid receptor-like receptor (OPRL1). PNOC functions as a transmitter in the brain by modulating nociceptive and locomotor behavior. The PNOC protein may also be involved in neuronal differentiation and development.

CNN1 is a member of the calponin family. CNN1 is a thin filament-associated protein which is involved in the regulation and modulation of smooth muscle contraction. CNN1 is able to bind to actin, calmodulin, troponin C and tropomyosin. Prevention of actomyosin Mg-ATPase activity is a result of interaction between calponin and actin.

CCR4-Not transcription complex, subunit 7 (CNOT7) is a ubiquitous transcription factor. CNOT7 is a component of the CCR4 complex which functions as a general transcription regulation complex. Furthermore, CNOT7 binds to an anti-proliferative protein, BTG1 (B-cell translocation protein 1), which negatively regulates cell proliferation.

Haptoglobin is a glycoprotein which is synthesized in the liver and circulates in the blood. Haptoglobin is produced typically by hepatocytes but also by other tissues: e.g. skin, lung, and kidney. It is a positive acute phase protein that binds free hemoglobin and removes it from the circulation to prevent kidney injury, and iron loss following hemolysis. The haptoglobin-hemoglobin complex is subsequently removed by the reticuloendothelial system (generally the spleen). As the reticuloendothelial system removes the haptoglobin-hemoglobin complex from the body, haptoglobin levels are reduced in hemolytic anaemias. In the course of binding hemoglobin, haptoglobin sequesters the iron inside hemoglobin, preventing iron-utilizing bacteria from benefitting from hemolysis.
Haptoglobin consists of two A- and two B-chains, connected by disulfide bonds. Three major haptoglobin phenotypes are known to exist (Hp 1-1, Hp 2-1, and Hp 2-2). Hp 1-1 is biologically the most effective in binding free hemoglobin and suppressing inflammatory responses associated with free hemoglobin. Hp 2-2 is biologically the least active, and Hp 2-1 is moderately active. Haptoglobin’s molecular mass ranges from 8-200 kDa.
Reduced levels can be seen in haemolysis and impaired liver function. High levels are a marker for acute or chronic inflammation. Ahaptoglobinemia or hypohaptoglobinemia are caused by mutations in the haptoglobin gene and/or its regulatory regions. Haptoglobin is also linked to diabetic nephropathy, the incidence of coronary artery disease in type 1 diabetes, Crohn's disease, inflammatory disease behavior, primary sclerosing cholangitis, susceptibility to idiopathic Parkinson's disease, and a reduced incidence of Plasmodium falciparum malaria.

Streptavidin is a tetrameric protein secreted by Streptomyces avidinii which binds firmly to biotin. Streptavidin is wilyde 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.

Gankyrin (proteasome 26S subunit) is a multicatalytic proteinase oncoprotein commonly overexpressed in most hepatocellular carcinomas. Proteasomes are found throughout eukaryotic cells at a high concentrations and cleave peptides in an ATP/ubiquitin-dependent process in a non-lysosomal pathway. Gankyrin interacts with S6 ATPase of the 19S regulatory particle of the 26S proteasome. Gankyrin is involved in theregulation of the phosphorylation of the retinoblastoma protein by CDK4, and to enhance the ubiquitinylation of p53 by MDM2. Gankyrin consists of 7 ankyrin repeats and is structurally similar to I kappa Bs. Gankyrin acts as a regulatory subunit of the 26s proteasome which is involved in the atp-dependent degradation of ubiquitinated proteins. Gankyrin is involved in progression of esophageal squamous cell carcinoma. gankyrin plays an oncogenic role especially in early stages of human epatocarcinogenesis. Gankyrin binds to NF-kappaB and suppresses its activity at the transcription level by modulating acetylation through SIRT1. Structural comparison between Gankyrin & p16(INK4A) identified numerous residues of gankyrin that are potentially important for CDK4 binding.

GSTP1 is a polymorphic gene encoding active, functionally different GSTP1 variant proteins that are believed to function in xenobiotic metabolism and have a part in susceptibility to cancer, and other diseases. GSTP1 is a glutathione S-transferase belonging to the pi class. GST family enzymes play a significant role in detoxification by catalyzing the conjugation of many hydrophobic and electrophilic compounds with reduced glutathione. Based upon the biochemical, immunologic and structural properties of the soluble GSTs they are grouped into 4 main classes: alpha, mu, pi, and theta. The GSTP1 enzyme acts by catalyzing the reaction of glutathione with an acceptor molecule to form a Sulfur-substituted glutathione. The reactions employing glutathione contribute the transformation of a broad range of electrophiles, including reactive products of lipid, protein, carcinogens, therapeutic drugs, environmental toxins, and products of oxidative stress.
The GSTP1 inactivation through CpG hypermethylation is frequent in pituitary adenomas and may be a factor in aggressive pituitary tumor behavior. GSTP1 is may be a transcriptional target of the p53 tumor suppressor gene. Single-nucleotide polymorphism in GSTP1 is linked to modified protein binding, which influence GSTP1's contribution to carcinogen and drug metabolism, and possibly disease pathogenesis and/or drug response. GST-pi might have central roles in proliferation of androgen-independent human prostate cancer cells.

MAPKSP1 is a scaffold protein which operates in the extracellular signal-regulated kinase (ERK) cascade. MAPKSP1 protein is restricted to late endosomes by the mitogen-activated protein-binding protein-interacting protein, and binds specifically to MAP kinase kinase MAP2K1/MEK1, MAP kinase MAPK3/ERK1, and MAP kinase MAPK1/ERK2.

U2 small nuclear ribonucleoprotein A (SNRPA1), a 255 amino acid protein, is a component of the U2 snRNP which forms a complex with U2 snRNP B (U2B). U2 snRNP A and U2 snRNP B form together a complex which binds to the U2 snRNA hairpin IV. The configuration of the U2 snRNP A/U2 snRNP B dimer and the delicate variations of a few key residues regulate the snRNP-RNA-binding specificity.

Testican-3 (Spock3) is a nervous system-expressed heparan sulfate proteoglycan belonging to a subgroup of the BM-40/SPARC/osteonectin family, whose role of in brain development is unclear. Spock3 inhibits the processing of pro-matrix metalloproteinase 2(MMP-2) by MT1-MMP and MT3-MMP. Spock3 is mostly confined to the developmental stage of the brain.

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, β, γ, ε, σ, ζ, τ and η that have been identified in mammals. The 14-3-3 epsilon, 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 CDC25 phosphatases, RAF1 and IRS1 proteins, suggesting its role in diverse biochemical activities related to signal transduction, such as cell division and regulation of insulin sensitivity. It has also been implicated in the pathogenesis of small cell lung cancer.

XCL1 is a small cytokine belongs to the XC chemokine family that is also known as lymphotactin. XCL1 is found in high levels in spleen, thymus, intestine and peripheral blood leukocytes, and at lower levels in lung, prostate gland and ovary. Cellular sources for XCL1 include activated thymic and peripheral blood CD8+ T cells. This chemokine attracts T cells. In humans, XCL1 is closely related to XCL2, whose gene is found at the same locus on chromosome 1. XCL1 induces it chemotactic function by binding to a chemokine receptor called XCR1.

Exenatide Derived from the saliva of the gila monster, is a 39 amino acid peptide that mimics the GLP-1 incretin, an insulin secretagogue with glucoregulatory effects. Typical responses to exenatide include improvements in the initial rapid release of endogenous insulin, suppression of glucagon release by the pancreas, regulation of gastric empyting, and reduced appetite - all of which function to lower blood glucose. Exenatide is self-regulating in that it lowers blood sugar when levels are elevated but does not continue to lower blood sugar when levels return to normal, unlike with sulfonylureas or insulins.

Entry of HSV into the host cell involves interactions of several viral glycoproteins with cell surface receptors. The virus particle is covered by an envelope which, when bound to specific receptors on the cell surface, will fuse with the cell membrane and create an opening, or pore, through which the virus enters the host cell. The sequential stages of HSV entry are analagous to those of other viruses. At first, complementary receptors on the virus and cell surface bring the two membranes into proximity. In an intermediate state, the two membranes begin to merge, forming a hemifusion state. Finally, a stable entry pore is formed through which the viral envelope contents are introduced to the host cell.