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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.

SDCBP2 has two class II PDZ domains. PDZ domains assist protein-protein interactions by attaching to the cytoplasmic C-terminus of transmembrane proteins, and PDZ-containing proteins mediate cell signaling and the organization of protein complexes. SDCBP2 attaches to phosphatidylinositol 4, 5-bisphosphate (PIP2) and take part in nuclear PIP2 arrangement and cell division.

Trafficking protein particle complex 4 (TRAPPC4) is part of the multisubunit TRAPP (transport protein particle) complex and interacts with SDC2. TRAPPC4 has a role in vesicular transport from endoplasmic reticulum to Golgi.

Synaptic vesicle membrane docking and fusion is mediated by SNAREs (soluble N-ethylmaleimide-sensitive factor attachment protein receptors) located on the vesicle membrane (v-SNAREs) and the target membrane (t-SNAREs). The assembled v-SNARE/t-SNARE complex consists of a bundle of four helices, one of which is supplied by v-SNARE and the other three by t-SNARE. For t-SNAREs on the plasma membrane, the protein syntaxin supplies one helix and the protein encoded by this gene contributes the other two. Therefore, SNAP25 product is a presynaptic plasma membrane protein involved in the regulation of neurotransmitter release. The synaptosomal-associated protein (SNAP-25) is an essential component of the core complex that mediates presynaptic vesicle trafficking. Thus, SNAP-25 is directly involved in the release of neurotransmitters.

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.

Synaptic vesicle membrane protein VAT-1 homolog (VAT1) is a member of the quinone oxidoreductase subfamily of zinc-containing alcohol dehydrogenase proteins. Synaptic vesicles are in charge of regulating the storage and release of neurotransmitters in the nerve terminal. VAT1 has an increased calcium ion-dependent expression in glioblastomas and on wounding, in basal keratinocytes. VAT1 is an abundant integral membrane protein of cholinergic synaptic vesicles and is believed to be involved in vesicular transport.

NAPA is part of the SNAP (Soluble NSF Attachment Protein) family. SNAPs, acting together with SNAREs (SNAP receptors) and the N-ethylmaleimide-sensitive fusion protein (NSF), are necessary for the fusion of transport vesicles to their objective membranes in synaptic transmission, intra-Golgi transport, endosome-to-endosome fusion and transcytotic vesicles-to-plasma membrane transport. NAPA is in charge of the binding of NSF and therefore the formation of a 20S fusion particle.

Adiponectin is an adipocyte specific secreted protein that circulates in the plasma. It is induced during adipocyte differentiation and its secretion is stimulated by insulin. Mouse adiponectin shares about 83% amino acid identity with that human. Adiponectin plays a role in various physiological processes such as energy homeostasis and obesity. Adiponectin is reduced in obese humans, and decreased level is associated with insulin resistance and hyperinsulinemia.

STX6 is a member of the syntaxin family and has 1 t-SNARE coiled-coil homology domain. STX6 takes part in intracellular vesicle transferring. STX6 binds EEA1 and Interacts with VPS45A, MARCH2, MARCH3 and GOPC. It is found in a complex comprising STX6, STX12, VAMP4 and VTI1A.

Syntaxin-binding protein 6 (STXBP6) binds components of the SNARE complex and takes part in regulating SNARE complex configuration. STXBP6 forms non-fusogenic complexes with SNAP25 and STX1A and modulates the formation of SNARE complexes and exocytosis.

XCL1 is a small cytokine belonging to the XC chemokine family that is also known as lymphotactin. It is located 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 another chemokine called 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.

Adiponectin is a hormone exclusively expressed from adipose tissue. Many studies demonstrate that adiponectin has direct anti-diabetic, anti-atherogenic and anti-inflammatory functions. APM-1 can increase insulin sensitivity of skeletal muscle, attenuate hepatic lipogenesis and luconeogenesis, regulate NO production in endothelial cells, inhibit proliferation of smooth muscle cells and prevent lipid accumulation of macrophage cells.
In the circulation, adiponectin is present as three different oligomeric complexes, including the high molecular weight (HMW), the middle molecular weight (MMW, also called hexamer) and low molecular weigh (MMW, also called trimer) forms 8. Different oligomeric complex of adiponectin activates different signaling pathways and exerts distinct functions.

Chemokine (C motif) ligand (XCL1) is a small cytokine belonging to the XC chemokine family that is also known as lymphotactin. It 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 another chemokine called XCL2, whose geneis found at the same locus on chromosome 1. XCL1 induces it chemotactic function by binding to a chemokine receptor called XCR1.

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.

Cysteine-rich PDZ-binding protein, also known as CRIPT, takes part in the cytoskeletal anchoring of DLG4 in excitatory synapses.

SORBS3 is an SH3 domain-containing adaptor protein. The existence of SH3 domains in the SORBS3 protein have a role in its capability to attach to other cytoplasmic molecules and contribute to cystoskeletal organization, cell adhesion and migration, signaling, and gene expression. Various transcript variants encoding different isoforms are known for this gene.

Syndecan 2 (SDC2) is a conserved family of heparan- and chondroitin-sulfate carrying transmembrane protein. Syndecan 2 is a cell membrane proteoglycan which modulates the activity and dynamics of some growth factor receptors and integrins. SDC2 is expressed in HSCs (hepatic stellate cells), a key cell type involved in matrix deposition in liver fibrotic disorders. SDC2 is implicated in the formation of specialized membrane domains and serves as a direct link between the extracellular environment and the organization of the cortical cytoplasm.

Synaptonemal complex central element protein 3 (SYCE3) is key component of the transverse central element of synaptonemal complexes (SCS). The synaptonemal complex is a protein structure which forms between homologous chromosomes (2 pairs of sister chromatids) during meiosis and is assumed to mediate chromosome pairing, synapsis, and recombination (crossing-over). The SYCE3 protein is essential for chromosome loading of the central element-specific SCS proteins, as well as for initiating synapsis between homologous chromosomes. SYCE3 is also vital for fertility.

Synaptobrevin-2 or VAMP2 is a protein that has a proline-rich N-terminal part, highly conserved hydrophilic domain, a transmembrane anchor and a C-terminal.VAMP2 found in the transmembrane region of the cell, in the cytoplasmic surface of the synaptic vesicle. The protein is mainly found in the Langerhans islets in the pancreas and glomerular cells in the kidney. A SNARE complex is created within the protein’s N-terminal domain and the target membrane-associated T.

α-Synuclein (amino acids 1-140), an acidic neuronal protein of 140 amino acids, is extremely heat-resistant and is natively unfolded with an extended structure primarily composed of random coils. α-synuclein has been suggested to be implicated in the pathogenesis of Parkinson’s disease and related neurodegenerative disorders, and more recently, to be an important regulatory component of vesicular transport in neuronal cells. Moreover, recent studies have shown that α-synuclein has chaperone activity and that this activity is lost upon removing its C-terminal acidic tail (amino acids 96-140).

PSMG4 is a chaperone protein that enhances assembly of the 20S proteasome. PSMG4 cooperates with alpha and beta subunits of the 20S proteasome and with PSMG3 but disconnects when the POMP is recruited before the formation of half-proteasomes.

MAP1LC3B is a member of the MAP1 LC3 family. MAP1LC3B is a subunit of neuronal microtubule-associated MAP1A and MAP1B proteins, that are involved in microtubule assembly and important for neurogenesis. In addition, MAP1LC3B takes part in formation of autophagosomal vacuoles and is expressed mainly in heart, testis, brain and skeletal muscle.

SNAP23 is a non-neuronal SNAP25 protein homologue and a target SNARE ubiquitously expressed on the plasma membrane and other intracellular membranes. SNAP23 is involved in exocytotic membrane fusion in most cells that do not express SNAP-25. SNAP23 is an essential component of the high affinity receptor for the general membrane fusion machinery and an crucial regulator of transport vesicle docking and fusion. SNAP23 is phosphorylated in platelets through cell activation during a protein kinase C-related mechanism at two or more sites. SNAP23, the ubiqitously expressed homologue of SNAP25, interacts directly with ubiquitous kinesin heavy chain (uKHC). SNAP-23 is expressed in human eosinophils and is a candidates for association with VAMP-2 during docking, which is followed by exocytosis.

NANOG is a multidomain homeobox transcription factor which functions to maintain the undifferentiated state of pluripotent stem cells. NANOG expression counteracts the differentiation-promoting signals induced by the extrinsic factors LIF, Stat3 and BMP. Once NANOG expression is downregulated, cell differentiation can proceed. Proteins which regulate NANOG expression include transcription factors Oct4, SOX2, FoxD3, and Tcf3 and tumor suppressor p53.