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Antibodies to Snare Complex Proteins ANTIBODIES TO SNARE COMPLEX PROTEINS Antibodies to SNARE Complex Proteins Synaptophysin VAMP/Synaptobrevin SNAP-25 Syntaxin CDCrel-1 Synaptotagmin-1 Munc18-1 Synapsin-1 INTERNATIONAL VERSION www.cedarlanelabs.com/SNARE CEDARLANE® is an ISO 9001 and ISO 13485 registered company Antibodies to SNARE Complex Proteins SNARE proteins are a large protein superfamily consisting of more than 60 members in yeast and mammals. The primary role of these proteins is to mediate fusion of vesicles with their target membrane-bound compartments (such as lysosomes). The most well studied SNARE proteins are those involved in mediating synaptic vesicle docking at the pre-synaptic membrane of neurons. During this process, syntaxin-1, SNAP-25 and munc18-1 associate and form a complex at the pre-synaptic membrane. This complex interacts with synaptobrevin-2 and synaptotagmin-1 located in synaptic vesicles and initiates docking, priming and fusion at the membrane. This fusion event leads to release of the vesicle's cargo into the synaptic cleft, where it can ultimately interact with the post-synaptic neuron. Antibodies to: Synaptophysin Synaptophysin is a 38 KDa synaptic vesicle (SV) glycoprotein containing four transmembrane domains. It is present in SVs of the neuroendocrine system, brain, spinal cord, retina, adrenal medulla and at neuromuscular junctions. Synaptophysin acts as a marker for neuroendocrine tumours and has been used to study the distribution of synapses within the brain due to its ubiquity at these regions. Although the exact function of synaptophysin is still unknown, several lines of evidence suggest it may have many important roles in SV exo and endocytosis. These include regulation of SNARE assembly, fusion pore formation initiating neurotransmitter release, and activation of SV endocytosis. Additionally, it is thought that synaptophysin may have an important role in SV biogenesis. Several gene mutations in synaptophysin have been seen in families affected by X-linked intellectual disability, suggesting that dysfunction of this protein may play a role in the disease. Purified Anti-Human Synaptophysin (CL2702AP) VAMP/Synaptobrevin Staining of paraformaldehyde-fixed paraffin-embedded human cerebellum Synaptobrevins are highly conserved, small integral membrane proteins that are part of sections at 200x (A) and 400x (B) magnification with DAPI counterstain. the vesicle-associated membrane protein (VAMP) family. They are present in abundance Mouse anti-human Synaptophysin on synaptic vesicles and peptidergic secretory granules, as well as on secretory granules (CL2702AP) 1:500; Alexa Fluor 488 Goat of endocrine cells. Synaptobrevins, along with syntaxins and SNAP-25, are all proteins anti-mouse 1:500 (Molecular Probes) and Normal Goat Serum (blocking). involved in the formation of SNARE complexes. Alterations in gene expression and mutations of synaptobrevin have been observed in various neuropsychiatric disorders including ADHD, bipolar disorder, schizophrenia and major depressive disorder. In addition, synaptobrevin is cleaved and inactivated by the light chain of the tetanus toxin (TeNT); this affects stability of the SNARE core complex, thereby inhibiting neurotransmitter exocytosis. SNAP-25 Synaptosomal-associated protein 25 (SNAP-25) is a membrane-bound protein localized to the cytosolic face of the pre-synaptic membrane. SNAP-25 is one component of the SNARE core complex, which also includes syntaxin-1 and synaptobrevin-2. Through interactions with these proteins and synaptotagmin, SNAP-25 regulates vesicle docking and fusion, and subsequently neurotransmitter release. SNAP-25 exists as two alternatively spliced isoforms, SNAP-25A and SNAP-25B, that are differentially expressed in neurons and neuroendocrine cells respectively. Recent studies have shown that some mutations in SNAP-25 may predispose humans to attention deficit hyperactivity disorder (ADHD). These findings are consistent with the fact that SNAP-25 reduces Ca2+ responsiveness at glutamatergic synapses. Alterations in gene expression levels of SNAP-25 have also been observed in other neuropsychiatric disorders, including schizophrenia and epilepsy. 2 www.cedarlanelabs.com – ANTIBODIES TO SNARE COMPLEX PROTEINS FROM CEDARLANE Syntaxin Syntaxin-1 is a 35 KDa integral membrane protein that possesses a single C-terminal transmembrane domain, a SNARE domain (H3) and an N-terminal regulatory domain (Habc). Two isoforms of syntaxin 1 have been identified, syntaxin-1A and syntaxin-1B. Syntaxin-1A localizes to nerve terminals of sensory neurons and nerve fibres reaching small blood vessels; syntaxin-1B is localized to motor end plates and muscle spindles. Deficits in syntaxin-1 phosphorylation by CK2 were observed in several cases of schizophrenia. Lower levels of phosphorylation were shown to reduce binding of syntaxin-1 to SNAP-25 and Munc18-1, leading to decreased SNARE complex formation. Also, the expression level of syntaxin-1A was seen to correlate with intelligence in individuals with the neurodevelopmental disorder Williams syndrome. CDCrel-1 Purified Anti-Human Syntaxin CDCrel-1/Septin-5 (Sept5) belongs to the septin family of nucleotide binding GTPases. (CL2706AP) Septins were originally described in yeast as cell division cycle regulatory proteins Staining of paraformaldehyde-fixed paraffin-embedded human cerebellum involved in cytokinesis and the regulation of cytoskeletal organization. Sept5 is sections at 200x (A) and 400x (B) expressed in cells of the nervous system and is seen to associate primarily with vesicles magnification with DAPI counterstain. and membranes through its interaction with the SNARE domain of syntaxin-1A. Through Mouse anti-human Syntaxin (CL2706AP) 1:500; Alexa Fluor 488 Goat anti-mouse its interaction with syntaxin-1A, Sept5 acts to inhibit exocytosis, possibly by regulating 1:500 (Molecular Probes) and Normal vesicle targeting and/or fusion. Recently it was shown that Sept5 is phosphorylated Goat Serum (blocking). by cyclin-dependent kinase 5 (Cdk5)–p35, decreasing its binding to syntaxin-1A. This suggests that Cdk5 can modulate synaptic vesicle release by regulating the interactions between Sept5 and syntaxin-1A. Synaptotagmin-1 Synaptotagmin-1 is a synaptic vesicle membrane protein that belongs to the synaptotagmins family; it is characterized by an N-terminal transmembrane region Purified Anti-Human Syntaxin (TMR), a variable linker, and two C-terminal C2-domains. Synaptotagmin-1, the first (CL2707AP) synaptotagmin studied, is an abundant synaptic vesicle protein that binds Ca2+ and Staining of paraformaldehyde-fixed 2+ paraffin-embedded human cerebellum phospholipids via both of its C2 domains and is essential for fast Ca -triggered sections at 400x magnification with DAPI neurotransmitter release. counterstain. Mouse anti-human Syntaxin (CL2707AP) 1:500; Alexa Fluor 488 Goat anti-mouse 1:500 Molecular Probes) and Normal Goat Serum (blocking). Munc18-1 Syntaxin-binding protein 1 (STXBP1) or munc18-1 is an abundant neuronal protein that tightly binds to synaptic fusion protein syntaxin, and functions in synaptic vesicle docking and fusion. Munc18-1 modulates neurotransmission through its interaction with syntaxin 1 and is thought to help restrict fusion of vesicles to specific sites of the plasma membrane. Deletion of munc18-1 leads to defects in secretory vesicle docking and the absence of neurotransmitter release. Defects in munc18-1 are the cause of epileptic encephalopathy early infantile type 4 (EIEE4). Affected individuals have neonatal or infantile onset of seizures and suppression-bursts. Purified Anti-Human CDCrel-1/Septin 5 (CL2708AP) Staining of paraformaldehyde-fixed paraffin-embedded human cerebellum sections at 400x magnification with DAPI counterstain. Mouse anti-human CDCrel-1/Septin 5 (CL2708AP) 1:500; Alexa Fluor 488 Goat anti-mouse 1:500 (Molecular Probes) and Normal Goat Serum (blocking). continued on next page ANTIBODIES TO SNARE COMPLEX PROTEINS FROM CEDARLANE – www.cedarlanelabs.com 3 Antibodies to SNARE Complex Proteins Synapsin-1 Synapsin-1 plays a key role in synaptic plasticity in brain. This effect is due in large part to the ability of the synapsins to regulate the availability of synaptic vesicles for release. In addition to its role in plasticity, the expression of synapsin-1 is a precise indicator of synapse formation. Thus, synapsin-1 immunocytochemistry provides a valuable tool for the study of synaptogenesis. The role of synapsin in synaptic plasticity and in synaptogenesis is regulated by phosphorylation. Immunostaining of cultured rat Western blot of hippocampal (Hipp) lysate caudate neurons with anti-synapsin-1 (10 μg) showing specific immunolabeling (CLN254AP) and anti-MAP showing of the ~78 KDa synapsin I doublet protein. punctate distribution of synapsin (green) and MAP (red). Specificity Format Clone Isotype Species Reactivity Applications Size Cat. # Synaptophysin Purified SP15 Mouse IgM Human WB, E, F 200 µg CL2702AP VAMP/Synaptobrevin Purified SP10 Mouse IgM Human WB, E, F 200 µg CL2703AP SNAP-25 Purified SP12 Mouse IgG1 Human WB, E, F 200 µg CL2705AP Biotin SP12 Mouse IgG1 Human WB, E, F 100 µg CL2705B FITC SP12 Mouse IgG1 Human F 100 µg CL2705F Syntaxin Purified SP6 Mouse IgG1 Human WB, E, F 200 µg CL2706AP Biotin SP6 Mouse IgG1 Human WB, E, F 100 µg CL2706B FITC SP6 Mouse IgG1 Human F 100 µg CL2706F Purified SP8 Mouse IgG1 Human WB, E, F 200 µg CL2707AP Biotin SP8 Mouse IgG1 Human WB, E, F 100 µg CL2707B FITC SP8 Mouse IgG1 Human F 100 µg CL2707F CDCrel-1 Purified SP18 Mouse
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