Syntaxin-16, a putative Golgi t-SNARE.
Members of the syntaxin family of integral membrane proteins have recently been implicated as vesicle receptors on target membranes, coresponsible for the specificity of intracellular membrane traffic. So far, only a small number of different mammalian syntaxins have been identified. Here we report the cloning of three new human syntaxin cDNAs, presumably originating from alternative splicing of the same transcript. Syntaxin-16A and syntaxin-16B are identical, except that the latter contains an insertion of 21 amino acid residues. Syntaxin-16C is a truncated version of syntaxin-16A, lacking the C-terminal coiled-coil and hydrophobic regions characteristic for syntaxins. Database searches identified putative yeast, plant and nematode homologues of syntaxin-16, indicating that this protein is conserved through evolution, and syntaxin-16 belongs to a new subgroup of syntaxins. Epitope-tagged syntaxin-16A and syntaxin-16B were found to colocalize with the Golgi marker beta-COP, while syntaxin-16C was found in the cytosol. Syntaxin-16A associates posttranslationally with microsomes, and appears to be transported to the Golgi via the endoplasmic reticulum. The three syntaxin-16 forms may have differential roles in intracellular trafficking.
Simonsen
A
A
Department of Biochemistry, The Norwegian Radium Hospital, Montebello, Oslo.
Bremnes
B
B
Rønning
E
E
Aasland
R
R
Stenmark
H
H
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D006224:Cricetinae; D018076:DNA, Complementary; D004721:Endoplasmic Reticulum / Q000378:metabolism; D015870:Gene Expression; D006056:Golgi Apparatus / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism; D008861:Microsomes / Q000378:metabolism; D008969:Molecular Sequence Data; D011499:Protein Processing, Post-Translational; D051438:Syntaxin 16
D018076:DNA, Complementary; D008565:Membrane Proteins; D051438:Syntaxin 16