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SNAPIN is involved in the neurotransmitter release process through its modulation of the sequential interactions between the SNAREs and synaptotagmin. SNAPIN is part of the SNARE complex of proteins that is needed for synaptic vesicle docking and fusion. SNAPAP is enriched in neurons and exclusively located on synaptic vesicle membrane protein. SNAPIN is also an important factor of the BLOC1 multisubunit protein complex. BLOC1 is required for normal biogenesis of specialized organelles of the endosomal-lysosomal system, such as melanosomes and platelet dense granules.

SNF8 belongs to the SNF8 family of vacuolar sorting proteins and is restricts to both the nucleus and the cytoplasm. SNF8 is a subunit of the endosomal sorting complex essential for transport II (ESCRT-II), which is necessary for multivesicular body (MVB) formation and sorting of endosomal cargo proteins into MVBs. The MVB pathway facilitates transfer of transmembrane proteins into the lumen of the lysosome for degradation. Additionally, the ESCRT-II complex takes part in transcription regulation by contributing to derepression of transcription by RNA polymerase II, probably by its interface with ELL.

S100G (calbindin D9K) is a vitamin D-dependent calcium-binding protein. S100G, which is a cytosolic protein, is a member of a family of calcium-binding proteins that includes calmodulin, parvalbumin, troponin C, and S100 protein. In the intestine, S100G is vitamin D-dependent and its expression correlates with calcium transport activity. S100G may increase Ca2+ absorption by buffering Ca2+ in the cytoplasm and increase ATP-dependent Ca2+ transport in duodenal basolateral membrane vesicles.

TSLP protein is a hemopoietic cytokine which signals throughout a heterodimeric receptor complex composed of the thymic stromal lymphopoietin receptor & the Interleukin-7 receptor alpha chain. TSLP impacts myeloid cells thus induces the discharge of T cell-attracting chemokines from monocytes & increases the growth of CD11c(+) dendritic cells. TSLP is mainly expressed in the heart, liver and prostate. TSLP is related in its biological activities with IL-7 and binds with the heterodimeric receptor complex consisting of the Interleukin-7 receptor alpha chain & the TSLPR. Similar to IL-7, TSLP enhances phosphorylation of STAT3 and STAT5, though uses kinases excluding JAKs for its activation. TSLP induces the release of T cell-attracting chemokines such asTARC & MDC from monocytes & triggers CD11c(+) dendritic cells. TSLP activated dendritic cells primes naive T cells to manufacture pro-allergic cytokines such as Iinterleukin-4, Interleukin-5, Interleukin-13 and TNF-alpha whereas down-regulating Interleukin-10 and IFN-gamma play a role in the initiation of allergic inflammation.

Excess adiposity is the most important risk in the development of insulin resistance and type 2 diabetes mellitus (T2DM). Adipose tissue produces several proteins (adipocytokines) such as leptin, adiponectin, resistin, tumor necrosis factor-?, and IL-6, that modulate insulin sensitivity and appear to play an important role in the pathogenesis of insulin resistance, diabetes, dyslipidemia, inflammation, and atherosclerosis. However, the mechanisms by which fat tissue induces insulin resistance and the role of adipocytokines in the pathogenesis of T2DM have not been well established.
Visfatin, also known as pre-B cell colony-enhancing factor (PBEF), is a cytokine that is highly expressed in visceral fat and was originally isolated as a secreted factor that synergizes with IL-7 and stem cell factors to promote the growth of B cell precursors. Visfatin homologs have been identified in carp, invertebrate mollusks, and bacteria, as well as in vertebrates, including humans and the mouse. It has been postulated to play a role in innate immunity.
Visfatin exerts insulin-mimetic effects that are dose-dependent and quantitatively similar to those of insulin in stimulating muscle and adipocyte glucose transport, and in inhibiting hepatocyte glucose production. Intravenous injection of recombinant visfatin in mice decreased plasma glucose in a dose-dependent fashion. In keeping with its insulin-mimetic effects, visfatin was as effective as insulin in reducing hyperglycemia in insulin-deficient diabetic mice. Visfatin was also found to be bound to and activate insulin receptor, causing receptor phosphorylation and the activation of downstream signaling molecules. However, visfatin and insulin did not compete for binding to the insulin receptor, indicating that the two proteins were recognized by different regions of the receptor. Thus, visfatin might play a role in glucose homeostasis and dysregulation in biosynthesis or signal transduction, and might contribute to the pathogenesis of diabetes.

RANKL binds to tnfrsf11b/opg and to tnfrsf11a/rank. Osteoclast differentiation and activation factor. Augments the ability of dendritic cells to stimulate naive t-cell proliferation. May be an important regulator of interactions between t-cells and dendritic cells and may play a role in the regulation of the t-cell-dependent immune response. sRANKL may also play an important role in enhanced bone-resorption in humoral hypercalcemia of malignancy.

Tachykinin-1 (TAC1) belongs to the tachykinin peptide hormone family. TAC1 are a family of peptides which have similar biologic activities and share a common C-terminal sequence, phe-X-gly-leu-met-NH2, however they have distinct N-terminal sequences that convey receptor specificities. TAC1 is assumed to act as neurotransmitters which interact with nerve receptors and smooth muscle cells. TAC1 induces behavioral responses and serves as vasodilators and secretagogues.

Intein is a section of a protein which can remove itself and return the remaining segment with a peptide bond. In addition, Inteins hold an endonuclease domain which takes part in Intein proliferation. Actually, various genes have unrelated intein-coding segments inserted at altered positions and they were found in all three domains of life (eukaryotes, bacteria, and archaea) and in viruses.

SCP2 sterol-binding domain containing 1 also known as SCP2D1 contains 1 SCP2 domain. One of the diseases associated with SCP2D1 is d-bifunctional protein deficiency.

Vimentin expression in human malignant glioma cells depends on cellular density, algorithms of drug delivery and chemo/radio treatment. Vimentin and detyrosinated microtubules provide structural support for the extensive microtentacles observed in detached tumor cells and a mechanism to promote successful metastatic spread. Primary colorectal carcinomas display aberrant expression of vimentin, and have activated Notch and TGFbeta signaling pathways. Vimentin is a strong arterial substrate for transglutaminases. Transglutaminase-mediated vimentin dimerization results in a novel unifying pathway by which vasodilatory and remodeling responses may be regulated. Ablation of vimentin expression inhibits migration and invasion of colon and breast cancer cell lines. Vimentin is the main intermediate filament protein in mesenchymal cells and is therefore of value in the differential diagnosis of undifferentiated neoplasms.

Cystatin-A is the intracellular inhibitor of cysteine proteinase cathepsin B (CatB) and belongs to family 1 of the cystatin superfamily of inhibitor proteins. CSTA is a stefin that functions as a cysteine protease inhibitor, forming tight complexes with papain and the cathepsins B, H, and L. It has been proposed that extracellular CatB together with other classes of proteinases are all subjected to a cascade-like manner of activation. CatB and its inhibitor Cystatin-A are involved in degradation of extracellular matrix proteins during tissue remodeling. CSTA is one of the precursor proteins of cornified cell envelope in keratinocytes and plays a role in epidermal development and maintenance. Cystatin-A has been reported to be found in high concentrations in epithelial cells, polymorphonuclear leukocytes and lymphoid tissue. Stefins may be used as prognostic and diagnostic tools for cancer.

IFN-tau is also known as TP-1 (trophoblast protein-1) is a new class of type I IFN that is secreted by the trophoblast and is the signal for maternal recognition of pregnancy in sheep. IFN- tau has potent immunosuppressive and antiviral activities similar to other type I IFN but is less cytotoxic than IFN-alpha and IFN-beta. The current investigation concerns the effect of recombinant ovine IFN- tau (rOIFN- tau) on the modulation of MHC class I and II expression on cloned mouse cerebrovascular endothelial (CVE) cells.
IFN-tau induced tyrosine phosphorylation of Stat1 and upregulated the expression of MHC class I on CVE. One proposed action by which type I IFN reduces the relapse rate in MS is via interference with IFN-?-induced MHC class II expression. IFN- tau was shown to downregulate IFN-?-induced MHC class II expression on CVE and, hence, may be of potential therapeutic value in downregulating inflammation in the central nervous system (CNS). IFN- tau did not upregulate the expression of MHC class II on CVE. IFN- tau also inhibited the replication of Theiler's virus in CVE.

Fractalkine soluble form is chemotactic for t-cells and monocytes, but not for neutrophils. Fractalkine membrane-bound form promotes adhesion of those leukocytes to endothelial cells. Fractalkine regulates leukocyte adhesion and migration processes at the endothelium and binds to CX3CR1. Fractalkine gene is located on human chromosome 16 along with some CC chemokines known as CCL17 and CCL22.

Protein A is a cell wall component produced by several strains of Staphylococcus aureus. The recombinant Protein A is genetically engineered protein and holds 5 IgG-binding regions of protein A. Recombinant Protein A functions basically the same as native Protein A and is perfect for purification of polyclonal or monoclonal IgG antibodies. Protein A binds to human IgG1, IgG2 and IgG4, mouse IgG2a, IgG2b and IgG3 and rat IgG2c. Protein A also binds to total IgG from rabbit, pig, dog, cat, and guinea pig.

RANKL binds to tnfrsf11b/opg and to tnfrsf11a/rank. Osteoclast differentiation and activation factor. Augments the ability of dendritic cells to stimulate naive t-cell proliferation. May be an important regulator of interactions between t-cells and dendritic cells and may play a role in the regulation of the t-cell-dependent immune response. sRANKL may also play an important role in enhanced bone-resorption in humoral hypercalcemia of malignancy.

Oncostatin M is a member of a cytokine family that includes leukemia-inhibitory factor, granulocyte colony-stimulating factor, and interleukin 6. This gene encodes a growth regulator which inhibits the proliferation of a number of tumor cell lines. It regulates cytokine production, including IL-6, G-CSF and GM-CSF from endothelial cells.

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.

26S proteasome complex subunit DSS1 (SHFM1) has been suggested as a candidate gene for the autosomal dominant form of the heterogeneous limb developmental disorder split hand/split foot malformation type 1. SHFM1 is a subunit of the 26S proteasome which plays a part in ubiquitin-dependent proteolysis. SHFM1 binds and stabilizes BRCA2 and is therefore involved in the control of R-loop-associated DNA damage and thus transcription-associated genomic instability. Furthermore, SHFM1 may have a role in the completion of the cell cycle. SHFM1 is a component of the TREX-2 complex (transcription and export complex 2), comprised of at least ENY2, GANP, PCID2, DSS1, and either centrin CETN2 or CETN3.

ST6GAL1 also known as ST6 Beta-Galactosamide Alpha-2,6-Sialyltranferase 1, is part of the glycosyltransferase family 29. ST6GAL1 is a type II membrane protein which catalyzes the transfer of sialic acid from CMP-sialic acid to galactose-containing substrates. Furthermore, ST6GAL1 is normally found in the Golgi however it can be proteolytically processed to a soluble form, ST6GAL1 is also involved in the generation of the cell-surface carbohydrate determinants as well differentiation antigens HB-6, CD75, and CD76.

PPIH is a part of the peptidyl-prolyl cis-trans isomerase (PPIase) family. PPIases catalyze the cis-trans isomerization of proline imidic peptide bonds in oligopeptides and increase protein folding. PPIH enzyme is a precise factor of the complex that comprises pre-mRNA processing factors PRPF3, PRPF4, and PRPF18, as well as U4/U5/U6 tri-snRNP. PPIH possess PPIase activity and acts as a protein chaperone that mediates the interactions between different proteins inside the spliceosome.

Recombinant Human Sonic Hedgehog is part of a small group of secreted proteins that are vital for development in both vertebrates and invertebrates. 3 mammalian hedgehog genes (sonic, desert, Indian) share about 60% homology. The Human Sonic Hedgehog is 99% homologous to the mouse gene. Sonic HedgeHog is a protein that is vital in guding the early embryo. It has been associated as the major inductive signal in patterning of the ventral neural tube, the anterior-posterior limb axis, and the ventral somites. Sonic HedgeHog binds to the patched receptor, which functions in association with smoothened, to activate the transcription of target genes. In the absence of sonic HedgeHog, patched receptor represses the constitutive signaling activity of smoothened. Sonic HedgeHog also regulates another factor, the gli oncogene. Sonic HedgeHog intercellular signal is essential for a various patterning events during development: signal produced by the notochord that induces ventral cell fate in the neural tube and somites, and the polarizing signal for patterning of the anterior-posterior axis of the developing limb bud. Sonic HedgeHog exhibits both floor plate- and motor neuron-inducing activity. Mutations in a long-range Sonic HedgeHog enhancer located in an intron of the limb region 1 gene result in preaxial polydactyly.

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.

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.

Lysostaphin, an endopeptidase specific for the cell wall peptidoglycan of staphylococci, is an extremely potent anti-staphylococcal agent. Lysostaphin is used as a research and diagnostic tool. Because it lyses staphylococci efficiently, it is widely used when preparing staphylococcal DNA or other cellular components for genetic and biochemical studies and for the preparation of protoplasts for transformation. Preparation and analysis of bacterial DNA has become a powerful tool used by clinical and other microbiologists in epidemiological studies aimed at tracing sources of infection or bacterial contamination.