Synaptic Ras GTPase activating protein 1 homolog (rat), also known as SYNGAP1, is a protein

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...

 which in humans is encoded by the SYNGAP1 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...

. SYNGAP1 is a ras GTPase-activating protein that is critical for cognition and synapse

Chemical synapse

Chemical synapses are specialized junctions through which neurons signal to each other and to non-neuronal cells such as those in muscles or glands. Chemical synapses allow neurons to form circuits within the central nervous system. They are crucial to the biological computations that underlie...

 function. Mutations in humans cause mental retardation.

Function

Unc51.1

ULK2

Unc-51-like kinase 2 also known as ULK2 is an enzyme which in humans is encoded by the ULK2 gene. The gene is located within the Smith-Magenis syndrome region on chromosome 17.- Structure and function :...

 and SynGAP function cooperatively in axon

Axon

An axon is a long, slender projection of a nerve cell, or neuron, that conducts electrical impulses away from the neuron's cell body or soma....

 formation. SynGAP1 regulated AMPA receptor

AMPA receptor

The α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor is a non-NMDA-type ionotropic transmembrane receptor for glutamate that mediates fast synaptic transmission in the central nervous system . Its name is derived from its ability to be activated by the artificial glutamate analog AMPA...

 trafficking and excitatory transmission. SynGAP1 affects these characteristics by regulating the MAP kinase signaling pathway

MAPK/ERK pathway

The MAPK/ERK pathway is a chain of proteins in the cell that communicates a signal from a receptor on the surface of the cell to the DNA in the nucleus of the cell. The signal starts when a growth factor binds to the receptor on the cell surface and ends when the DNA in the nucleus expresses a...

.

Clinical significance

Several mutations in the SYNGAP1 gene were identified as the cause of mental retardation. Mental retardation is sometimes associated with syndromes of other defects caused by the same gene, but SYNGAP1-associated mental retardation is not; it is therefore called non-syndromic mental retardation. Since neither of the parents of children with this condition have the mutation, this means it was a sporadic mutation that occurred during division of the parents' gametes (meiosis

Meiosis

Meiosis is a special type of cell division necessary for sexual reproduction. The cells produced by meiosis are gametes or spores. The animals' gametes are called sperm and egg cells....

) or fertilization of the egg. It is a dominant mutation, which means that the individual will be retarded if only one allele

Allele

An allele is one of two or more forms of a gene or a genetic locus . "Allel" is an abbreviation of allelomorph. Sometimes, different alleles can result in different observable phenotypic traits, such as different pigmentation...

 is mutated.

Interactions

SYNGAP1 has been shown to interact

Protein-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 DLG3

DLG3

Disks large homolog 3 also known as neuroendocrine-DLG or synapse-associated protein 102 is a protein that in humans is encoded by the DLG3 gene...

 and ULK1

ULK1

Serine/threonine-protein kinase ULK1 is an enzyme that in humans is encoded by the ULK1 gene.-Interactions:ULK1 has been shown to interact with GABARAPL2, GABARAP, SYNGAP1 and SDCBP.-Further reading:...

.

Further reading