Table 1.
ER-phagy cargo receptors and functions
| FAM134B | RTN3L (RTN3 isoform e) |
SEC62 | CCPG1 | ATL3 | TEX264 | Atg39 (S.c.) |
Atg40 (S.c.) |
|
|---|---|---|---|---|---|---|---|---|
| Canonical isoform (NP_) |
001030022 | 001252518 | 003253 | 004739 | 056274 | 001123356 | 013415 | 014795 |
| Size (a.a.) | 497 | 1032 | 399 | 757 | 541 | 313 | 398 | 256 |
| LIR/AIM | 455-FELL-468 | 217-YSKV-220 248-FEVI-251 342-WDLV-345 555-FEEL-558 790-YDIL-793 |
363-FEMI-366 | 14-WTVI-17 | 192-YGRL-195 390-FKQL-393 |
273-FEEL-276 | 8-WNLV-11 | 242-YDFM-245 |
| FIR/Atg11BR | 18-SHEGSDIEMLNS-29 101-SDDSDIVTLE-110 |
52-DVLS NTSS-59 |
||||||
| ER sub-region | Sheet | Tubular | 192-YGRL-195 390-FKQL-393 |
Tubular (3-way junctions) | Nuclear envelope | Peripheral | ||
| ER anchor |
RHD | RHD | Two TM | Single pass TM | Two TM | Single pass TM | Single pass TM | RHD-like |
| Membrane reshaping activity? | RHD | RHD | Dynamin-like GTPase | RHD-like | ||||
| Stimulus | Nutrient starvation | Nutrient starvation | Recovery from UPR | UPR | Nutrient starvation | Nutrient starvation | Rapamycin | Rapamycin |
| Protein targets in ER-phagy? | PC clearance Mutant NPC1 |
Small role in PC clearance? | UPR induced chaperones | Exocrine enzymes & chaperones in pancreas Role in PC clearance? |
Broad rang Selectivity evident |
|||
| Altered in disease? |
Expression (HSAN II) |
Amplified (cancer) |
Point mutation (HSAN I) |
n/a | n/a |
Summary of the characteristics of the eight well-characterized ER-phagy receptors discussed in this review. All proteins are human isoforms except for those marked (S.c.) for yeast Saccharomyces cerevisiae. Abbreviations: a.a., amino acids; RHD, reticulon-homology domain; TM, transmembrane; HSAN, hereditary sensory neuropathy; UPR, unfolded protein response; PC, procollagen; ERLAD, ER-to-lysosome associated degradation; NP, NCBI Reference Sequence prefix. n/a, not applicable.