TY  - GEN
T1  - Glucose concentration does not affect degradation of a protein that aberrantly engages the endoplasmic reticulum translocon
AU  - Broshar, Courtney L
AU  - Rubenstein, Eric M
DO  - 10.17912/micropub.biology.000248
UR  - http://beta.micropublication.org/journals/biology/micropub-biology-000248/
AB  - Approximately one third of eukaryotic proteins enter the endoplasmic reticulum (ER) en route to their subcellular or extracellular destinations (Chen et al. 2005; Choi et al. 2010). Many of these proteins use the Sec61p translocon complex to cross the ER membrane (Aviram and Schuldiner 2017). Proteins that persistently engage the translocon prevent other proteins from reaching the ER (Izawa et al. 2012; Ast et al. 2016). Thus, cells have evolved multiple quality control mechanisms to degrade proteins that aberrantly occupy this channel (Rubenstein et al. 2012; Crowder et al. 2015; Ast et al. 2016). In ER-associated degradation of translocon-associated proteins (ERAD-T), such polypeptides are targeted for destruction by homologs of the ER-resident RING (really interesting new gene) domain ubiquitin ligase Hrd1p. Deg1*-Sec62 is an engineered model translocon-associated substrate for Hrd1p in yeast (Figure 1A). Analogously, in mammalian cells, the Hrd1p homolog gp78 promotes turnover of the low-density lipoprotein (LDL) component apolipoprotein B, which stalls in the translocon if it is unable to associate with LDL lipid molecules (Fisher et al. 2011).
PY  - 2020
JO  - microPublication Biology
ER  -