Longin is one of the approximately 26 components required for transporting proteins from the ER to the plasma membrane, via the Golgi apparatus. It is necessary for the steps of the transfer from the ER to the Golgi complex [1]. Longins are the only R-SNAREs that are common to all eukaryotes, and they are characterised by a conserved N-terminal domain with a profilin-like fold called a longin domain [2].

1: Identification of the yeast R-SNARE Nyv1p as a novel longin domain-containing protein. Wen W, Chen L, Wu H, Sun X, Zhang M, Banfield DK; Mol Biol Cell. 2006;17:4282-4299. PMID:16855025

2: Longins and their longin domains: regulated SNAREs and multifunctional SNARE regulators. Rossi V, Banfield DK, Vacca M, Dietrich LE, Ungermann C, D'Esposito M, Galli T, Filippini F; Trends Biochem Sci. 2004;29:682-688. PMID:15544955