Table 1.

Summary of processes, TRAP expression, possible TRAP function(s) and effects.

processes	TRAP expressions	TRAP functions	effects
co-translation protein translocation [26,28–30,32,38,40–42,47]	Sec61 and TRAP stoichiometric ratio 1 : 1	– assists Sec61 open state – chaperone: interaction with substrate	substrate-dependent
unfolded protein response (UPR) [62,69,70]	TRAP overexpressed	– chaperone: protein maturation – recognition of unfolded proteins	↑UPR
ER-associated protein degradation (ERAD) [62,69,70]	TRAP silencing	– secondary effect of UPR – retro-translocation	↓ERAD
protein glycosylation [61]	– TRAP δ absent – TRAP α, β, γ underexpressed	– chaperone: assists protein modification – interaction with OST – OST substrate of TRAP	ssr4 CDG: under-glycosylated