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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.

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.

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.

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.

SNAP-25 is an necessary element of the core complex that is responsible for presynaptic vesicle trafficking. Thus, SNAP-25 is directly involved in the release of neurotransmitters and this protein exists as two alternative isoforms, SNAP25A and SNAP25B which differ by 9 amino acids in central portion of these proteins.

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.

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.

Synaptotagmin-11 (SYT11) protein may be involved in Ca2+-dependent exocytosis of secretory vesicles through Ca2+ and phospholipid binding to the C2 domain or may function as Ca2+ sensors in the process of vesicular trafficking and exocytosis.

Vesicle-Associated Membrane Protein 7 (VAMP7) is a member of the synaptobrevin family. VAMP7 is a transmembrane protein, which is a member of the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) family. VAMP7 is involved in the targeting and/or fusion of transport vesicles to their target membrane during transport of proteins from the early endosome to the lysosome. VAMP7 localizes to late endosomes and lysosomes and is involved in the fusion of transport vesicles to their target membranes. VAMP7 is essential for heterotypic fusion of late endosomes with lysosomes and homotypic lysosomal fusion. It is also necessary for calcium regulated lysosomal exocytosis. In addition, VAMP7 is involved in the export of chylomicrons from the endoplasmic reticulum to the cis Golgi. Furthermore, VAMP7 is needed for exocytosis of mediators during eosinophil and neutrophil degranulation, and target cell killing by natural killer cells.

VAMP3 is present in recycling endosomes and endosome-derived vesicles. VAMP3 has been implicated in recycling of transferrin receptors to the plasma membrane, secretion of alpha-granules in platelets, recycling of T-cell receptors to the immunological synapses, and membrane trafficking during cell migration. VAMP-3 is present in human platelets and necessary for granule secretion. Synaptobrevins are the main components of a protein complex involved in the docking and/or fusion of synaptic vesicles with the presynaptic membrane. VAMP3 high homology to other VAMPs in its broad tissue distribution and subcellular localization is shown to be the human equivalent of the rodent cellubrevin. In platelets the protein resides on a compartment that is not mobilized to the plasma membrane on calcium or thrombin stimulation.

Synaptobrevin 2 which is an 18 kDa integral membrane protein localized to the cytoplasmic surface of synaptic vesicle, consists of a proline-rich N-terminal region, a highly conserved hydrophilic domain, followed by a transmembrane anchor and a C-terminal. Synaptobrevin 2 is predominantly expressed in Langerhans islets and glomerular cells. The N-terminal domain of the protein (residues 1-89) forms a specific SNARE complex with the target membrane-associated t- or Q-SNAREs syntaxin 1 and SNAP-25.

Microtubule-associated protein tau (MAPT or Tau) is a protein that stabilizes microtubules. MAPT is abundant in neurons in the central nervous system and is less common elsewhere. When MAPT is defective, and no longer stabilizes microtubules properly, it can result in dementias, such as Alzheimer's disease.

SYT13 belongs to the great synaptotagmin protein family which contain 2 domains: cytoplasmic C terminus with two tandem C2 domains (C2A and C2B) and extracellular N-terminal transmembrane domain. Synaptotogmin family members have dissimilar biochemical properties and developmental profiles, and patterns of tissue distribution. Additionally, Synaptotogmins formulate homo- and heteromeric complexes with each other. Synaptotagmins operate as membrane traffickers in multicellular organisms.

GABARAP is a ligand-gated chloride channel that mediates inhibitory neurotransmission. GABARAP is highly positively charged in its N-terminus and shares sequence similarity with light chain-3 of microtubule-associated proteins 1A and 1B. GABARAP clusters neurotransmitter receptors by mediating interaction with the cytoskeleton.

VAMP4 belongs to the synaptobrevin family who are involved in docking and/or fusion of vesicles with cell membrane. VAMP4 is enriched in the trans-Golgi network and may be a factor in the trans-Golgi network-to-endosome transport. VAMP4 is involved in the pathway which functions to eliminate an inhibitor (most likely synaptotagmin-4) of calcium-triggered exocytosis during the maturation of secretory granules. Synaptobrevins, syntaxins, and SNAP25 are the chief components of a protein complex involved in the docking and/or fusion of synaptic vesicles with the presynaptic membrane.

Synaptotagmin-3 (SYT3) is a member of the synaptotagmin family. SYT3 is involved in Ca(2+)-dependent exocytosis of secretory vesicles through Ca(2+) and phospholipid binding to the C2 domain or may function as Ca(2+) sensors in the process of vesicular trafficking and exocytosis.

SAP18 is a component of the histone deacetylase complex which has a significant role in the regulation of eukaryotic gene expression. SAP18 directly interacts with SIN3 and enhances SIN3-mediated transcriptional repression once bound to the promoter. SAP18 plays an important part in gene-specific recruitment of the HDAC complex by a number of transcription factors including Gli, GAGA, and Bicoid. Histone acetylation is significant in the regulation of eukaryotic gene expression. Histone acetylation and deacetylation is catalyzed by multisubunit complexes. SAP18 is a component of the histone deacetylase complex, which includes SIN3, SAP30, HDAC1, HDAC2, RbAp46, RbAp48, and other polypeptides. SAP18 is a component of a splicing-dependent multiprotein EJC (exon junction complex) placed at splice junction on mRNAs.

MAPT is a neuronal microtubule associated protein localized mostly on axons.
MAPT promotes tubulin polymerisation and stabilizes microtubules, however it also serves to connect certain signalling pathways to the cytoskeleton. MAPT, in its hyperphosphorylated form, is the main part of paired helical filaments (PHF) and neurofibrillary lesions in Alzheimer''s disease (AD) brain.

Microtubule-associated protein tau (MAPT or Tau) is a protein that stabilizes microtubules. MAPT is abundant in neurons in the central nervous system and is less common elsewhere. When MAPT is defective, and no longer stabilizes microtubules properly, it can result in dementias, such as Alzheimer's disease.

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.

Synaptotagmin-4 (SYT4) is a part of the synaptotagmin proteins family. Synaptotagmins are a large gene family of synaptic vesicle type III integral membrane proteins that operate as regulators of both exocytosis and endocytosis and are involved in neurotransmitter secretion from small secretory vesicles. SYT4 is expressed in neuronal tissues, and has the highest mRNA levels in the hippocampus. The proximity of the SYT4 gene to markers of several psychiatric disorders implies an involvement of SYT4 in human disease such as pheochromocytoma, and parkinson's disease.

Microtubule-associated proteins 1A/1B light chain 3 beta 2 (MAP1LC3B2) is a member of the MAP1LC3 family. MAP1LC3B2 is a subunit of neuronal microtubule-associated MAP1A and MAP1B proteins, which are involved in microtubule assembly and essential for neurogenesis. The MAP1LC3B2 protein is possibly involved in formation of autophagosomal vacuoles (autophagosomes). MAP1LC3B2 is expressed primarily in the heart, testis, brain and skeletal muscle.

MAPRE2 (RP1 or EB2) is an evolutionarily conserved protein, which associates with the tips of growing microtubules, and regulates microtubule dynamics and their interactions with intracellular structures. The EB proteins regulate microtubule function through CLIP proteins. MAPRE2 shares noteworthy homology to the adenomatous polyposis coli (APC) protein-binding EB1 gene family. MAPRE2 is necessary for spindle symmetry during mitosis. MAPRE2 is believed to have a role in the tumorigenesis of colorectal cancers and the proliferative control of normal cells.

GABARAPL1 [Gamma-aminobutyric acid (GABA) receptor-associated protein-like 1] is a member of the MAP1 LC3 family. GABARAPL1 increases cell surface expression of kappa type opioid receptor through facilitating anterograde intracellular trafficking of the receptor.