The COG complex, the peripheral membrane oligomeric protein complex involved in intra-Golgi protein trafficking, consists of eight subunits arranged in two lobes bridged by Cog1. Cog5 is in the smaller, B lobe, bound in with Cog6-8, and is itself bound to Cog1 as well as, strongly, to Cog7 [1,2]. This domain is found at the N-terminal of COG5 and includes the LLR motif which is important to interact with COG7 [2]. Disruption of COG5-COG7 interface does not impair lobe B but causes aberrant cell surface glycosylation with major deficits in the trafficking of Golgi glycosyltransferases [2].

1: Cog1p plays a central role in the organization of the yeast conserved oligomeric Golgi complex. Fotso P, Koryakina Y, Pavliv O, Tsiomenko AB, Lupashin VV; J Biol Chem. 2005;280:27613-27623. PMID:15932880

2: Cog5-Cog7 crystal structure reveals interactions essential for the function of a multisubunit tethering complex. Ha JY, Pokrovskaya ID, Climer LK, Shimamura GR, Kudlyk T, Jeffrey PD, Lupashin VV, Hughson FM; Proc Natl Acad Sci U S A. 2014;111:15762-15767. PMID:25331899