Syntaxin-10 is a SNARE

Snare

Snare may refer to:* Snare trap, a kind of trap used for capturing animals* Snare drum* SNARE , a family of proteins involved in vesicle fusion* The Snares, a group of islands approximately 200 kilometres south of New Zealand...

 protein that is encoded by the STX10 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...

. This protein is found in most vertebrates (including humans) but is noticeably absent from mice. As with other SNARE proteins, STX10 facilitates vesicle fusion

Vesicle fusion

Vesicle fusion is the merging of a vesicle with other vesicles or a part of a cell membrane. In the latter case, it is the end stage of secretion from secretory vesicles, where their contents are expelled from the cell through exocytosis at the porosome...

 and thus is important for intracellular trafficking

Protein targeting

Protein targeting or protein sorting is the mechanism by which a cell transports proteins to the appropriate positions in the cell or outside of it. Sorting targets can be the inner space of an organelle, any of several interior membranes, the cell's outer membrane, or its exterior via secretion...

  of proteins and other cellular components. More specifically, STX10 has been implicated in endosome

Endosome

In biology, an endosome is a membrane-bound compartment inside eukaryotic cells. It is a compartment of the endocytic membrane transport pathway from the plasma membrane to the lysosome. Molecules internalized from the plasma membrane can follow this pathway all the way to lysosomes for...

 to Golgi trafficking of the mannose 6-phosphate receptor

Mannose 6-phosphate receptor

In the fields of biochemistry and cell biology, mannose 6-phosphate receptors are proteins that bind newly synthesized lysosomal hydrolases in the trans-Golgi network and deliver them to pre-lysosomal compartments. There are two different MPRs, one of ~300kDa and a smaller, dimeric receptor of...

 and glucose transporter type 4

GLUT4

Glucose transporter type 4, also known as GLUT4, is a protein that in humans is encoded by the GLUT4 gene. GLUT4 is the insulin-regulated glucose transporter found in adipose tissues and striated muscle that is responsible for insulin-regulated glucose translocation into the cell...

.

STX10 has been detected in the trans-Golgi

Golgi apparatus

The Golgi apparatus is an organelle found in most eukaryotic cells. It was identified in 1898 by the Italian physician Camillo Golgi, after whom the Golgi apparatus is named....

 network (TGN) by immunofluorescence

Immunofluorescence

Immunofluorescence is a technique used for light microscopy with a fluorescence microscope and is used primarily on biological samples. This technique uses the specificity of antibodies to their antigen to target fluorescent dyes to specific biomolecule targets within a cell, and therefore allows...

.

Structure and function

Human STX10 is a 249 amino acid

Amino acid

Amino acids are molecules containing an amine group, a carboxylic acid group and a side-chain that varies between different amino acids. The key elements of an amino acid are carbon, hydrogen, oxygen, and nitrogen...

 protein that has three N-terminal α-helices

Alpha helix

A common motif in the secondary structure of proteins, the alpha helix is a right-handed coiled or spiral conformation, in which every backbone N-H group donates a hydrogen bond to the backbone C=O group of the amino acid four residues earlier...

 and a single SNARE domain

Protein domain

A protein domain is a part of protein sequence and structure that can evolve, function, and exist independently of the rest of the protein chain. Each domain forms a compact three-dimensional structure and often can be independently stable and folded. Many proteins consist of several structural...

 followed by a single-pass transmembrane

Transmembrane protein

A transmembrane protein is a protein that goes from one side of a membrane through to the other side of the membrane. Many TPs function as gateways or "loading docks" to deny or permit the transport of specific substances across the biological membrane, to get into the cell, or out of the cell as...

 domain. Human STX10 is 60% identical to human STX6

STX6

Syntaxin-6 is a protein that in humans is encoded by the STX6 gene.-Interactions:STX6 has been shown to interact with SNAP23, VAMP3 and VAMP4.-Further reading:...

.

STX10 is structurally classified as a Qc-SNARE (contributes a glutamine

Glutamine

Glutamine is one of the 20 amino acids encoded by the standard genetic code. It is not recognized as an essential amino acid but may become conditionally essential in certain situations, including intensive athletic training or certain gastrointestinal disorders...

 (Q) residue in the formation of the assembled core SNARE complex) and is functionally classified as a t-SNARE

Snare

Snare may refer to:* Snare trap, a kind of trap used for capturing animals* Snare drum* SNARE , a family of proteins involved in vesicle fusion* The Snares, a group of islands approximately 200 kilometres south of New Zealand...

 (or target-SNARE which is often located in the membranes of target compartments).

Interactions

STX10 is known to interact with the t-SNAREs VTI1A

VTI1A

Vesicle transport through interaction with t-SNAREs homolog 1A is a protein that in humans is encoded by the VTI1A gene.The protein encoded by the VTI1A gene is a target-SNARE protein which is located in the membranes of target vesicle compartments....

 and STX16

STX16

Syntaxin-16 is a protein that in humans is encoded by the STX16 gene.It has been associated with pseudohypoparathyroidism type Ib.-Further reading:...

 and with the v-SNAREs VAMP3

VAMP3

Vesicle-associated membrane protein 3 is a protein that in humans is encoded by the VAMP3 gene.-Interactions:VAMP3 has been shown to interact with* BCAP31,* BVES,* SNAP23,* STX4,* STX6.-Further reading:...

 and VAMP4

VAMP4

Vesicle-associated membrane protein 4 is a protein that in humans is encoded by the VAMP4 gene.-Interactions:VAMP4 has been shown to interact with AP1M1, STX6 and STX16.-Further reading:...

. The SNARE complex of STX10, STX16

STX16

Syntaxin-16 is a protein that in humans is encoded by the STX16 gene.It has been associated with pseudohypoparathyroidism type Ib.-Further reading:...

, VTI1A, and VAMP3 are required for late endosome to Golgi trafficking of the mannose 6-phosphate receptor

Mannose 6-phosphate receptor

In the fields of biochemistry and cell biology, mannose 6-phosphate receptors are proteins that bind newly synthesized lysosomal hydrolases in the trans-Golgi network and deliver them to pre-lysosomal compartments. There are two different MPRs, one of ~300kDa and a smaller, dimeric receptor of...

. Early endosome to Golgi trafficking of Shiga toxin requires the SNARE complex of STX6

STX6

Syntaxin-6 is a protein that in humans is encoded by the STX6 gene.-Interactions:STX6 has been shown to interact with SNAP23, VAMP3 and VAMP4.-Further reading:...

, STX16, VTI1A, and VAMP3 or VAMP4.

Thus, STX10 distinguishes early endosome to Golgi trafficking from late endosome to Golgi trafficking.