Syntaxin-10 (STX10) is a

SNARE 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 fu ...

protein that is encoded by the ''STX10''

gene In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a ba ...

. 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 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. Vesicles c ...

and thus is important for intracellular

trafficking Smuggling is the illegal transportation of objects, substances, information or people, such as out of a house or buildings, into a prison, or across an international border, in violation of applicable laws or other regulations. There are various ...

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

endosome Endosomes are a collection of intracellular sorting organelles in eukaryotic cells. They are parts of endocytic membrane transport pathway originating from the trans Golgi network. Molecules or ligands internalized from the plasma membrane can ...

to Golgi trafficking of the

mannose 6-phosphate receptor The mannose 6-phosphate receptors (MPRs) are transmembrane glycoproteins that target enzymes to lysosomes in vertebrates. Mannose 6-phosphate receptors bind newly synthesized lysosomal hydrolases in the trans-Golgi network (TGN) and deliver th ...

and glucose transporter type 4. STX10 has been detected in the trans- Golgi network (TGN) by

immunofluorescence Immunofluorescence is a technique used for light microscopy with a fluorescence microscope and is used primarily on microbiological samples. This technique uses the specificity of antibodies to their antigen to target fluorescent dyes to specif ...

Structure and function

Human STX10 is a 249

amino acid Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha am ...

protein that has three

N-terminal The N-terminus (also known as the amino-terminus, NH2-terminus, N-terminal end or amine-terminus) is the start of a protein or polypeptide, referring to the free amine group (-NH2) located at the end of a polypeptide. Within a peptide, the ami ...

α-helices The alpha helix (α-helix) is a common motif in the secondary structure of proteins and is a right hand-helix conformation in which every backbone N−H group hydrogen bonds to the backbone C=O group of the amino acid located four residues ear ...

and a single SNARE

domain Domain may refer to: Mathematics *Domain of a function, the set of input values for which the (total) function is defined **Domain of definition of a partial function **Natural domain of a partial function **Domain of holomorphy of a function * Do ...

followed by a single-pass

transmembrane A transmembrane protein (TP) is a type of integral membrane protein that spans the entirety of the cell membrane. Many transmembrane proteins function as gateways to permit the transport of specific substances across the membrane. They frequentl ...

domain. Human STX10 is 60% identical to human STX6. STX10 is structurally classified as a Qc-SNARE (contributes a

glutamine Glutamine (symbol Gln or Q) is an α-amino acid that is used in the biosynthesis of proteins. Its side chain is similar to that of glutamic acid, except the carboxylic acid group is replaced by an amide. It is classified as a charge-neutral, ...

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

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

Interactions

STX10 is known to interact with the t-SNAREs

VTI1A Vesicle transport through interaction with t-SNAREs homolog 1A is a protein that in humans is encoded by the ''VTI1A'' gene In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of ...

and

STX16 Syntaxin-16 is a protein that in humans is encoded by the ''STX16'' gene. It has been associated with pseudohypoparathyroidism type Ib. Losing this gene causes loss of methylation at GNAS1 exon A/B. Interactions STX16 has been shown to inter ...

and with the v-SNAREs

VAMP3 Vesicle-associated membrane protein 3 is a protein that in humans is encoded by the ''VAMP3'' gene. Function Synaptobrevins/VAMPs, syntaxins, and the 25-kD synaptosomal-associated protein are the main components of a protein complex involved i ...

and

VAMP4 Vesicle-associated membrane protein 4 is a protein that in humans is encoded by the ''VAMP4'' gene. Function Synaptobrevins/VAMPs, syntaxins, and the 25-kD synaptosomal-associated protein SNAP25 are the main components of a protein complex inv ...

. The SNARE complex of STX10,

, VTI1A, and VAMP3 are required for late endosome to Golgi trafficking of the

. Early endosome to Golgi trafficking of Shiga toxin requires the SNARE complex of STX6, STX16, VTI1A, and VAMP3 or VAMP4. Thus, STX10 distinguishes early endosome to Golgi trafficking from late endosome to Golgi trafficking.

References

External links

PDBe-KB
provides an overview of all the structure information available in the PDB for Human Syntaxin-10 (STX10) {{gene-19-stub