title: Syntaxin 12, a member of the syntaxin family localized to the endosome.
abstract: We have cloned a new member of the syntaxin family of proteins. The open reading frame encodes a polypeptide of 272 amino acids with potential coiled-coil domains and a C-terminal hydrophobic tail. Northern blot analysis showed that the transcript is fairly ubiquitous. A soluble recombinant form of the polypeptide without the hydrophobic region binds to alpha-SNAP (soluble N-ethylmaleimide-sensitive factor attachment protein) and syndet/SNAP-23 in vitro. Polyclonal antibody raised against the recombinant protein recognized a 39-kDa protein in the membrane fraction of cell lysates. Indirect immunofluorescence studies using the polyclonal antibody showed that the protein is localized to intracellular membrane structures. Selective permeabilization studies with digitonin and saponin indicate that the epitope(s) recognized by the antibody is expose to the cytoplasm, consistent with the predicted orientation characteristic of SNAP receptor molecules. Morphological alterations of the staining pattern of the protein with brefeldin A and wortmannin treatment indicate that the protein is localize to the endosome. The cDNA we have cloned apparently corresponded to three previously described expressed sequence tags named as syntaxins 12, 13, and 14, respectively. We therefore propose to retain the name syntaxin 12 for this protein.
authors.affiliation: Membrane Biology Laboratory, Institute of Molecular and Cell Biology, Singapore 117609, Republic of Singapore.
authors.forename: B L
authors.initials: BL
authors.lastname: Tang
authors.forename: A E
authors.initials: AE
authors.lastname: Tan
authors.forename: L K
authors.initials: LK
authors.lastname: Lim
authors.forename: S S
authors.initials: SS
authors.lastname: Lee
authors.forename: D Y
authors.initials: DY
authors.lastname: Low
authors.forename: W
authors.initials: W
authors.lastname: Hong
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D002460:Cell Line; D003001:Cloning, Molecular; D011992:Endosomes / Q000378:metabolism*; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D011485:Protein Binding; D050765:Qa-SNARE Proteins; D050600:SNARE Proteins; D033921:Vesicular Transport Proteins
chemical_list: D008565:Membrane Proteins; D050765:Qa-SNARE Proteins; D050600:SNARE Proteins; D033921:Vesicular Transport Proteins; C111366:syntaxin 12, rat