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Synaptotagmin
Synaptotagmins (SYTs) constitute a family of membrane-trafficking proteins that are characterized by an N-terminal transmembrane region (TMR), a variable linker, and two C-terminal C2 domains - C2A and C2B. There are 17 isoforms in the mammalian synaptotagmin family. There are several C2-domain containing protein families that are related to synaptotagmins, including transmembrane (Ferlins, Extended-Synaptotagmin (E-Syt) membrane proteins, and MCTPs) and soluble (RIMS1 and RIMS2, UNC13D, synaptotagmin-related proteins and B/K) proteins. The family includes synaptotagmin 1, a Ca2+ sensor in the membrane of the pre-synaptic axon terminal, coded by gene SYT1. Functions Based on their brain/endocrine distribution and biochemical properties, in particular C2 domains of certain synaptotagmins bound to calcium, synaptotagmins were proposed to function as calcium sensors in the regulation of neurotransmitter release and hormone secretion. Although synaptotagmins share a similar domain st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Syt1
Synaptotagmin-1 is a protein that in humans is encoded by the ''SYT1'' gene. Function Synaptotagmins are integral membrane proteins of synaptic vesicles thought to serve as sensors for calcium ions (Ca2+) in the process of vesicular trafficking and exocytosis. Calcium ion binding to synaptotagmin I participates in triggering neurotransmitter release at the synapse. OMIM] SYT1 is the master switch responsible for allowing the human brain to release neurotransmitters. SYT1 senses calcium ion concentrations as low as 10 ppm and subsequently signals the SNARE complex to open fusion pores. * Interactions SYT1 has been shown to interact with SNAP-25, STX1A Syntaxin-1A is a protein that in humans is encoded by the ''STX1A'' gene. Function Synaptic vesicles store neurotransmitters that are released during calcium-regulated exocytosis. The specificity of neurotransmitter release requires the localiz ... and S100A13. Clinical Significance Mutations in the ''SYT1'' gene cause ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SYT1
Synaptotagmin-1 is a protein that in humans is encoded by the ''SYT1'' gene. Function Synaptotagmins are integral membrane proteins of synaptic vesicles thought to serve as sensors for calcium ions (Ca2+) in the process of vesicular trafficking and exocytosis. Calcium ion binding to synaptotagmin I participates in triggering neurotransmitter release at the synapse. OMIM] SYT1 is the master switch responsible for allowing the human brain to release neurotransmitters. SYT1 senses calcium ion concentrations as low as 10 ppm and subsequently signals the SNARE complex to open fusion pores. * Interactions SYT1 has been shown to interact with SNAP-25, STX1A Syntaxin-1A is a protein that in humans is encoded by the ''STX1A'' gene. Function Synaptic vesicles store neurotransmitters that are released during calcium-regulated exocytosis. The specificity of neurotransmitter release requires the localiz ... and S100A13. Clinical Significance Mutations in the ''SYT1'' gene cause ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Complexin
Complexin (also known as synaphin) refers to a one of a small set of eukaryotic cytoplasmic neuronal proteins which binds to the SNARE protein complex (''SNAREpin'') with a high affinity. These are called synaphin 1 and 2. In the presence of Ca2+, the transport vesicle protein synaptotagmin displaces complexin, allowing the SNARE protein complex to bind the transport vesicle to the presynaptic membrane. Complexin acts as both an inhibitor and a facilitator of synaptic vesicle fusion and neurotransmitter release. In one conformation, it clamps ''SNAREpin'' complexes, preventing vesicle fusion, while in a different conformation it releases the ''SNAREpins'', allowing synaptotagmin to trigger fusion. Whereas complexin is not necessary for synaptic vesicle exocytosis, it does increase neurotransmitter release by 60–70% as demonstrated by complexin gene knockout in mice. A number of human neurological diseases have been linked to a deficiency of complexin. Synaphin can promote exo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SNARE (protein)
SNARE proteins – " SNAP REceptor" – are a large protein family consisting of at least 24 members in yeasts, more than 60 members in mammalian cells, and some numbers in plants. The primary role of SNARE proteins is to mediate vesicle fusion – the fusion of vesicles with the target membrane; this notably mediates exocytosis, but can also mediate the fusion of vesicles with membrane-bound compartments (such as a lysosome). The best studied SNAREs are those that mediate the neurotransmitter release of synaptic vesicles in neurons. These neuronal SNAREs are the targets of the neurotoxins responsible for botulism and tetanus produced by certain bacteria. Types SNAREs can be divided into two categories: ''vesicle'' or ''v-SNAREs'', which are incorporated into the membranes of transport vesicles during budding, and ''target'' or ''t-SNAREs'', which are associated with nerve terminal membranes. Evidence suggests that t-SNAREs form stable subcomplexes which serve as guides f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
