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Signal-Regulatory Protein Gamma (SIRPG) belongs to the signal-regulatory protein (SIRP) family whose members are receptor-type transmembrane glycoproteins which negatively regulate the receptor tyrosine kinase-coupled signaling processes. SIRPG is also a part of the immunoglobulin superfamily.

NF-kappa-B inhibitor beta (NFKBIB) is a member of the NF-kappa-B inhibitor family, which inhibit NF-kappa-B by complexing with, and trapping it in the cytoplasm. Phosphorylation of serine residues on these proteins by kinases marks them for destruction via the ubiquitination pathway, thus allowing activation of the NF-kappa-B, which translocates to the nucleus to act as a transcription factor.

A natural cytotoxicity receptor (NCR) NKp46 has been shown to represent a novel NK cell-specific molecule involved in human NK cell activation. The natural cytotoxicity receptors (NCRs) are a recently characterized family of Ig-like activation receptors that appear to be major triggering receptors in tumor cell recognition. The three known NCRs include NKp46 and NKp30, which are expressed on circulating NKcells, and NKp44, which is expressed only on activating NK cells. NKp46 has been implicated in NK cell-mediated lysis of several autologous tumor cells, pathogen-infected cell lines and mononuclear phagocytes infected with an intracellular bacterium. The Lysis of tumor cells by NK-cells involves recognition by NKp46 of heparan sulfate moieties of membrane heparan sulfate proteoglycans. Furthermore, NKp46 is a surface receptor involved in NK-cell cell death by apoptosis. NKp46 has two extracellular Ig-like domains followed by a ~40 residue stalk region, a type I transmembrane domain, and a short cytoplasmic tail. The extracellular Ig-like domain of NKp46 (22-255aa) is purified by FPLC gel-filtration chromatography, after refolding of the isolated inclusion bodies in a redox buffer. In addition, engagement of the antigen with the monoclonal antibody stimulates intracellular calcium levels and the synthesis of cytokines. CD59 is an NKp46 coreceptor (by physical association) together they activate cytotoxicity of human NK-cells, their engagement results in tyrosine phosphorylation of CD3-zeta chains associated with NKp46. Reduced cell surface expression of NKp46 and other NK-cell receptors is linked to the impaired NK-cell cytolytic function in viremic HIV-1 infection.

Syntaxin-1, synaptobrevin, and SNAP25 cooperate to form the SNARE complex, which is needed for synaptic vesicle docking and fusion SNPH is a neuron-specific protein originally characterized as a binding partner of syntaxin-1. SNPH participates with SNAP25 for the binding to Syntaxin-1 and prevents the construction of the SNARE core complex, thus manageling free syntaxin-1 availability for the assembly of the SNARE complex and potentially regulating synaptic vesicle exocytosis. Expression Syntaphilin appears to be brain-specific. SNPH is an inhibitor of both SNARE-based fusion and dynamin-mediated endocytosis.

NRTN belongs to the GDNF family of ligands, a distant member of the TGF-beta superfamily. NRTN, a ligand used to bind to GFRA2 receptors, signals through RET and a GPI-linked coreceptor, and promotes endurance of neuronal populations, controls the size of non-neuronal cell population such as haemopoietic cells and regulate the development and maintenance of the CNS. Mutation in NRTN results in Hirschsprung Disease.

Trypsin inhibitor SPINK1 is secreted from pancreatic acinar cells into pancreatic fluid. SPINK1 has a role in inhibition of trypsin-catalyzed premature initiation of zymogens in the pancreas and the pancreatic duct. Alterations in SPINK1 gene are the cause for tropical calcific and pancreatitis hereditary pancreatitis.

Neurexophilin 1 (NXPH1) is a part of the neurexophilin family which encodes a secreted protein with a variable N terminal domain, an extremely conserved, N-glycosylated central domain, a short linker region, and a cysteine-rich Cterminal domain. NXPH1 shapes a very tight complex with alpha neurexins, a group of proteins which promote adhesion among dendrites and axons.

SRP14 is a ribonucleoprotein complex which mediates the directing of proteins to the endoplasmic reticulum. The “Alu domain” of SRP is comprised of the heterodimer of the SRP9 and SRP14 proteins that are bound to the 5' and 3' terminal sequences of SRP RNA. SRP9/14 binding may be critical to the transcription, maturation, nucleolus localization and transport of SRP RNA.

Stratifin is part of the 14-3-3 family. The 14-3-3 family of proteins plays an important regulatory function in signal transduction, checkpoint control, apoptotic and nutrient-sensing pathways. 14-3-3 proteins are highly conserved and ubiquitously expressed. There are 7 isoforms, beta, gamma, epsilon, sigma, zeta, tau and eta that have been identified in mammals. Stratifin is an epithelial cell marker that functions as a tumor suppressor whose expression can be down regulated via methylation. Failure of Stratifin expression results in a defective G2/M phase checkpoint and results in epithelial and non-epithelial tumorigenesis.

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.

FANK1 was localized in the nuclei of identical cells in the seminiferous epithelium. Depending on its nuclear localization, a gene ontology analysis proposes that FANK1 has a DNA binding activity therefor operates as a transcription factor. The extremely controlled expression of FANK1, suggests that it takes part in regulating gene expression in the transition from the meiotic phase to the haploid phase throughout spermatogenesis.

TBCB is a member of the Microtubules family. Biosynthesis of functional microtubules include the involvement of a number of chaperones, termed Tubulin folding cofactors A (TBCA), B (TBCB), C (TBCC), D (TBCD) and E (TBCE), which operate on folding intermediates downstream of the cytosolic chaperon, known as TCP. The 244 amino acid cytoplasmic protein TBCB has one CAP-Gly domain and is universally expressed. TBCB takes part in the regulation of tubulin heterodimer dissociation and operates as a negative regulator of axonal growth.

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.

CBX1 is an enriched heterochromatin which belongs to the heterochromatin protein family. The centromeres related CBX1 identifies and binds histone H3 tails methylated at 'Lys-9', causing epigenetic repression. Collaboration with lamin B receptor (LBR) can impact the relations between the heterochromatin and the inner nuclear membrane. CBX1 has a vital part in the epigenetic control of chromatin structure and gene expression.

Peptidyl-prolyl cis-trans isomerase FKBP1B (FKBP1B) belongs to the immunophilin protein family which has a role in immunoregulation and basic cellular processes involving protein folding and trafficking. FKBP1B is a cis-trans prolyl isomerase which binds the immunosuppressants FK506 and rapamycin. FKBP1B is extremely similar to the FK506-binding protein 1A. The physiological role of FKBP1B is thought to be in excitation-contraction coupling in cardiac muscle.

CTK-19 is a member of the keratin family. The keratins are intermediate filament proteins responsible for the structural integrity of epithelial cells and are subdivided into cytokeratins and hair keratins. The type I cytokeratins consist of acidic proteins which are arranged in pairs of heterotypic keratin chains. Unlike its related family members, this smallest known acidic cytokeratin is not paired with a basic cytokeratin in epithelial cells. It is specifically expressed in the periderm, the transiently superficial layer that envelopes the developing epidermis. The type I cytokeratins are clustered in a region of chromosome 17q12-q21.

Guanine nucleotide-binding protein G(z) subunit alpha (GNAZ) belongs to the G protein subfamily which mediates signal transduction in pertussis toxin-insensitive systems. GNAZ has a role in maintaining the ionic balance of perilymphatic and endolymphatic cochlear fluids. G proteins are involved as modulators or transducers in a variety of transmembrane signaling systems.

Calcium-binding protein P22 is a phosphoprotein that binds to the sodium-hydrogen exchangers (NHEs). CHP is an essential cofactor which maintains the physiological activity of NHE family members. CHP has protein sequence resemblance to calcineurin B and it is also identified to be an endogenous inhibitor of calcineurin activity.CHP is necessary for constitutive membrane traffic. CHP Inhibits GTPase-stimulated Na(+)/H(+) exchange. CHP inhibits calcineurin phosphatase activity. Required for activity of SLC9A1/NHE1.

Clathrin light chain B (CLTB) is a member of the clathrin light chain family. Clathrin is a protein that has a key role in the formation of coated vesicles. CLTB functions as the key structural component of the lattice-type cytoplasmic face of coated pits and vesicles which capture certain macromolecules during receptor-mediated endocytosis. CLTB forms a triskelion form comprised of 3 clathrin heavy chains and 3 light chains. When the triskelia interact they form a polyhedral pattern which encircles the vesicle. CME (Clathrin-mediated endocytosis) controls numerous cellular physiological processes such as the internalization of growth factors and receptors, entry of pathogens, and synaptic transmission.

MAP3K12 Binding Inhibitory Protein 1 (MBIP) is a part of the ATAC complex which consists of histones H3 and H4 with a histone acetyltransferase activity. MBIP inhibits the MAP3K12 activity in order to induce the activation of the JNK/SAPK pathway.

XIAP Associated Factor 1 (XAF1) is a protein which binds to and counteracts the inhibitory effect of a member of the IAP (inhibitor of apoptosis) protein family. IAP proteins bind to and inhibit caspases which are activated in the course of apoptosis. The ratio of IAPs and proteins which interfere with their activity, such as the XAF1 protein, influence the progress of the apoptosis signaling pathway. Additionally, XAF1 inhibits anti-caspase activity of BIRC4. XAF1 induces cleavage and inactivation of BIRC4 independent of caspase activation. Furthermore, XAF1 mediates TNF-alpha-induced apoptosis and is involved in apoptosis in trophoblast cells.

Retinoblastoma binding protein 4 (RBBP4) is a ubiquitously expressed nuclear protein which is a member of a highly conserved subfamily of WD-repeat proteins. RBBP4 is present in protein complexes involved in histone acetylation and chromatin assembly. In addition, RBBP4 is part of co-repressor complexes, which is a fundamental component of transcriptional silencing. RBBP4 is observed among several cellular proteins which bind directly to a retinoblastoma protein to regulate cell proliferation. RBBP4 also is a part of the Mi-2 complex which is implicated in chromatin remodeling and transcriptional repression connected with histone deacetylation.

YWHAB belongs to the 14-3-3 family of proteins which are in charge for signal transduction by binding to phosphoserine-containing proteins. YWHAB is found in both plants and mammals. YWHAB protein interacts with RAF1 and CDC25 phosphatases,thus linking mitogenic signaling and the cell cycle machinery. YWHAB is an adapter protein involved in the regulation of a large spectrum of both general and specialized signaling pathway. YWHAB binds to a large number of proteins by recognition of a phosphoserine or phosphothreonine motif. Binding generally results in the modulation of the activity of the binding partner.

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.