| First Author | Kouroku Y | Year | 2007 |
| Journal | Cell Death Differ | Volume | 14 |
| Issue | 2 | Pages | 230-9 |
| PubMed ID | 16794605 | Mgi Jnum | J:132345 |
| Mgi Id | MGI:3775718 | Doi | 10.1038/sj.cdd.4401984 |
| Citation | Kouroku Y, et al. (2007) ER stress (PERK/eIF2alpha phosphorylation) mediates the polyglutamine-induced LC3 conversion, an essential step for autophagy formation. Cell Death Differ 14(2):230-9 |
| abstractText | Expanded polyglutamine 72 repeat (polyQ72) aggregates induce endoplasmic reticulum (ER) stress-mediated cell death with caspase-12 activation and vesicular formation (autophagy). We examined this relationship and the molecular mechanism of autophagy formation. Rapamycin, a stimulator of autophagy, inhibited the polyQ72-induced cell death with caspase-12 activation. PolyQ72, but not polyQ11, stimulated Atg5-Atg12-Atg16 complex-dependent microtubule-associated protein 1 (MAP1) light chain 3 (LC3) conversion from LC3-I to -II, which plays a key role in autophagy. The eucaryotic translation initiation factor 2 alpha (eIF2alpha) A/A mutation, a knock-in to replace a phosphorylatable Ser51 with Ala51, and dominant-negative PERK inhibited polyQ72-induced LC3 conversion. PolyQ72 as well as ER stress stimulators upregulated Atg12 mRNA and proteins via eIF2alpha phosphorylation. Furthermore, Atg5 deficiency as well as the eIF2alpha A/A mutation increased the number of cells showing polyQ72 aggregates and polyQ72-induced caspase-12 activation. Thus, autophagy formation is a cellular defense mechanism against polyQ72-induced ER-stress-mediated cell death by degrading polyQ72 aggregates, with PERK/eIF2alpha phosphorylation being involved in polyQ72-induced LC3 conversion. |
