High impact information on CUE1

• Here, a membrane-bound component of the ubiquitin system, Cue1p, was identified [1].
• The region required for monoubiquitin binding mapped to the Vps9 CUE domain, a sequence previously identified by database searches as similar to parts of the yeast Cue1 and mammalian Tollip proteins [2].
• Degradation further requires the activity of Cue1p-assembled Ubc7p, and its own catalytic site cysteine [3].
• The Mps2-1p mutant protein level is markedly reduced compared to wild-type Mps2p, and deletion of CUE1 restores the level of Mps2-1p to nearly wild-type levels [4].
• Cells lacking UBC7, CUE1, or DOA10 were cold sensitive, suggesting that these ERAD proteins have a role in cold adaptation, perhaps through effects on sterol biosynthesis [5].

Anatomical context of CUE1

• Yeast strains lacking UBC7, CUE1, or DOA10 also assembled aberrant karmellae (ordered arrays of membranes surrounding the nucleus that assemble when HMGR is expressed at high levels) [5].

Physical interactions of CUE1

• Cue1p interacts with the ERAD E2 Ubc7p in vivo [6].

Other interactions of CUE1

• Cue1p has been shown to recruit the soluble ubiquitin-conjugating enzyme, Ubc7p, to the cytoplasmic face of the ER membrane where it can ubiquitinate its substrates and target them for degradation by the proteasome [4].

References