| Full text | |
| Author(s): |
Silva, Richard C.
;
Sattlegger, Evelyn
;
Castilho, Beatriz A.
Total Authors: 3
|
| Document type: | Journal article |
| Source: | Journal of Cell Science; v. 129, n. 24, p. 4521-4533, DEC 15 2016. |
| Web of Science Citations: | 8 |
| Abstract | |
Genetic and pharmacological interventions in yeast and mammalian cells have suggested a cross-talk between the actin cytoskeleton and protein synthesis. Regulation of the activity of the translation initiation factor 2 (eIF2) is a paramount mechanism for cells to rapidly adjust the rate of protein synthesis and to trigger reprogramming of gene expression in response to internal and external cues. Here, we show that disruption of F-actin in mammalian cells inhibits translation in a GCN2-dependent manner, correlating with increased levels of uncharged tRNA. GCN2 activation increased phosphorylation of its substrate eIF2a and the induction of the integrated stress response master regulator, ATF4. GCN2 activation by latrunculin-B is dependent on GCN1 and inhibited by IMPACT. Our data suggest that GCN2 occurs in two different complexes, GCN2-eEF1A and GCN2-GCN1. Depolymerization of F-actin shifts GCN2 to favor the complex with GCN1, concomitant with GCN1 being released from its binding to IMPACT, which is sequestered by G-actin. These events might further contribute to GCN2 activation. Our findings indicate that GCN2 is an important sensor of the state of the actin cytoskeleton. (AU) | |
| FAPESP's process: | 14/17145-4 - Translational regulation mediated by GCN2: modulation by the actin cytoskeleton |
| Grantee: | Richard Cardoso da Silva |
| Support Opportunities: | Scholarships in Brazil - Post-Doctoral |
| FAPESP's process: | 14/23889-6 - GCN1 and its interactor Yih1/IMPACT: their function in and beyond translational control |
| Grantee: | Beatriz Amaral de Castilho |
| Support Opportunities: | Research Grants - Visiting Researcher Grant - International |
| FAPESP's process: | 09/52047-5 - Translational regulation mediated by elF2 in eukaryotes |
| Grantee: | Beatriz Amaral de Castilho |
| Support Opportunities: | Research Projects - Thematic Grants |