This is the conserved N-terminal of Syntaxin-18. Syntaxin-18 is found in the SNARE complex of the endoplasmic reticulum and functions in the trafficking between the ER intermediate compartment and the cis-Golgi vesicle. In particular, the N-terminal region is important for the formation of ER aggregates [1]. More specifically, syntaxin-18 is involved in endoplasmic reticulum-mediated phagocytosis, presumably by regulating the specific and direct fusion of the ER with the plasma or phagosomal membranes [2].

1: Syntaxin 18, a SNAP receptor that functions in the endoplasmic reticulum, intermediate compartment, and cis-Golgi vesicle trafficking. Hatsuzawa K, Hirose H, Tani K, Yamamoto A, Scheller RH, Tagaya M; J Biol Chem. 2000;275:13713-13720. PMID:10788491

2: Involvement of syntaxin 18, an endoplasmic reticulum (ER)-localized SNARE protein, in ER-mediated phagocytosis. Hatsuzawa K, Tamura T, Hashimoto H, Hashimoto H, Yokoya S, Miura M, Nagaya H, Wada I; Mol Biol Cell. 2006;17:3964-3977. PMID:16790498