Synaptophysin
Encyclopedia
Synaptophysin also known as the major synaptic vesicle protein p38 is a protein
that in humans is encoded by the SYP gene
.
(Xp11.23-p11.22). It is 12,406 bases in length and lies on the Crick (minus) strand. The encoded protein has 313 amino acids with a predicted molecular weight of 33.845 kDa
.
glycoprotein
with four transmembrane domains weighing 38kDa. It is present in neuroendocrine cells
and in virtually all neurons in the brain
and spinal cord
that participate in synaptic transmission. It acts as a marker for neuroendocrine tumors, and its ubiquity at the synapse has led to the use of synaptophysin immunostaining for quantification of synapses.
The exact function of the protein is unknown: it interacts with the essential synaptic vesicle protein synaptobrevin
, but when the synaptophysin gene is experimentally inactivated in animals, they still develop and function normally. Recent research has shown, however, that elimination of synaptophysin in mice creates behavioral changes such as increased exploratory behavior, impaired object novelty recognition, and reduced spatial learning.
with AP1G1
and SIAH2
.
Protein
Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...
that in humans is encoded by the SYP gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
.
Genomics
The gene is located on the short arm of X chromosomeX chromosome
The X chromosome is one of the two sex-determining chromosomes in many animal species, including mammals and is common in both males and females. It is a part of the XY sex-determination system and X0 sex-determination system...
(Xp11.23-p11.22). It is 12,406 bases in length and lies on the Crick (minus) strand. The encoded protein has 313 amino acids with a predicted molecular weight of 33.845 kDa
Atomic mass unit
The unified atomic mass unit or dalton is a unit that is used for indicating mass on an atomic or molecular scale. It is defined as one twelfth of the rest mass of an unbound neutral atom of carbon-12 in its nuclear and electronic ground state, and has a value of...
.
Molecular biology
The protein is a synaptic vesicleSynaptic vesicle
In a neuron, synaptic vesicles store various neurotransmitters that are released at the synapse. The release is regulated by a voltage-dependent calcium channel. Vesicles are essential for propagating nerve impulses between neurons and are constantly recreated by the cell...
glycoprotein
Glycoprotein
Glycoproteins are proteins that contain oligosaccharide chains covalently attached to polypeptide side-chains. The carbohydrate is attached to the protein in a cotranslational or posttranslational modification. This process is known as glycosylation. In proteins that have segments extending...
with four transmembrane domains weighing 38kDa. It is present in neuroendocrine cells
Endocrine system
In physiology, the endocrine system is a system of glands, each of which secretes a type of hormone directly into the bloodstream to regulate the body. The endocrine system is in contrast to the exocrine system, which secretes its chemicals using ducts. It derives from the Greek words "endo"...
and in virtually all neurons in the brain
Brain
The brain is the center of the nervous system in all vertebrate and most invertebrate animals—only a few primitive invertebrates such as sponges, jellyfish, sea squirts and starfishes do not have one. It is located in the head, usually close to primary sensory apparatus such as vision, hearing,...
and spinal cord
Spinal cord
The spinal cord is a long, thin, tubular bundle of nervous tissue and support cells that extends from the brain . The brain and spinal cord together make up the central nervous system...
that participate in synaptic transmission. It acts as a marker for neuroendocrine tumors, and its ubiquity at the synapse has led to the use of synaptophysin immunostaining for quantification of synapses.
The exact function of the protein is unknown: it interacts with the essential synaptic vesicle protein synaptobrevin
Synaptobrevin
Synaptobrevins are small integral membrane proteins of secretory vesicles with molecular weight of 18 kilodalton that are part of the vesicle-associated membrane protein family....
, but when the synaptophysin gene is experimentally inactivated in animals, they still develop and function normally. Recent research has shown, however, that elimination of synaptophysin in mice creates behavioral changes such as increased exploratory behavior, impaired object novelty recognition, and reduced spatial learning.
Interactions
Synaptophysin has been shown to interactProtein-protein interaction
Protein–protein interactions occur when two or more proteins bind together, often to carry out their biological function. Many of the most important molecular processes in the cell such as DNA replication are carried out by large molecular machines that are built from a large number of protein...
with AP1G1
AP1G1
AP-1 complex subunit gamma-1 is a protein that in humans is encoded by the AP1G1 gene.-Interactions:AP1G1 has been shown to interact with RABEP1, AP1B1, Synaptophysin, AP1M1, NECAP2, AP1S1 and AP1GBP1.-Further reading:...
and SIAH2
SIAH2
E3 ubiquitin-protein ligase SIAH2 is an enzyme that in humans is encoded by the SIAH2 gene.-Interactions:SIAH2 has been shown to interact with PEG10, Synaptophysin, PEG3 and VAV1.-Further reading:...
.