Stimulators of translation identified during a small molecule screening campaign |
| |
| Authors: | Unkyung Shin David E Williams Dima Kozakov David R Hall Dmitri Beglov Sandor Vajda Raymond J Andersen Jerry Pelletier |
| |
| Institution: | 1. Department of Biochemistry, McGill University, Montreal, Quebec H3G 1Y6, Canada;2. Departments of Chemistry and Earth, Ocean, & Atmospheric Sciences, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada;3. Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA;4. Department of Oncology, McGill University, Montreal, Quebec H3G 1Y6, Canada;5. Rosalind and Morris Goodman Cancer Research Center, McGill University, Montreal, Quebec H3G 1Y6, Canada |
| |
| Abstract: | In screening a library of natural and synthetic products for eukaryotic translation modulators, we identified two natural products, isohymenialdisine and hymenialdisine, that exhibit stimulatory effects on translation. The characterization of these compounds led to the insight that mRNA used to program the translation extracts during high-throughput assay setup was leading to phosphorylation of eIF2α, a potent negative regulatory event that is mediated by one of four kinases. We identified double-stranded RNA-dependent protein kinase (PKR) as the eIF2α kinase that was being activated by exogenously added mRNA template. Characterization of the mode of action of isohymenialdisine revealed that it directly acts on PKR by inhibiting autophosphorylation, perturbs the PKR–eIF2α phosphorylation axis, and can be modeled into the PKR ATP binding site. Our results identify a source of “false positives” for high-throughput screen campaigns using translation extracts, raising a cautionary note for this type of screen. |
| |
| Keywords: | High-throughput screens Translation PKR eIF2α Isohymenialdisine Hymenialdisine |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
