1. Assessing eukaryotic initiation factor 4F subunit essentiality by CRISPR-induced gene ablation in the mouse
- Author
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Marilène Paquet, Regina Cencic, Jennifer Chu, Jerry Pelletier, Nahum Sonenberg, Akiko Yanagiya, Francis Robert, and Patrick Senechal
- Subjects
Pharmacology ,Regulation of gene expression ,0303 health sciences ,EIF4G ,EIF4E ,Cell Biology ,EIF4A1 ,Biology ,EIF4G3 ,Cell biology ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,Eukaryotic initiation factor 4F ,chemistry.chemical_compound ,0302 clinical medicine ,chemistry ,030220 oncology & carcinogenesis ,Eukaryotic initiation factor ,eIF4A ,Molecular Medicine ,Molecular Biology ,030304 developmental biology - Abstract
Eukaryotic initiation factor (eIF) 4F plays a central role in the ribosome recruitment phase of cap-dependent translation. This heterotrimeric complex consists of a cap binding subunit (eIF4E), a DEAD-box RNA helicase (eIF4A), and a large bridging protein (eIF4G). In mammalian cells, there are two genes encoding eIF4A (eIF4A1 and eIF4A2) and eIF4G (eIF4G1 and eIF4G3) paralogs that can assemble into eIF4F complexes. To query the essential nature of the eIF4F subunits in normal development, we used CRISPR/Cas9 to generate mouse strains with targeted ablation of each gene encoding the different eIF4F subunits. We find that Eif4e, Eif4g1, and Eif4a1 are essential for viability in the mouse, whereas Eif4g3 and Eif4a2 are not. However, Eif4g3 and Eif4a2 do play essential roles in spermatogenesis. Crossing of these strains to the lymphoma-prone Eμ-Myc mouse model revealed that heterozygosity at the Eif4e or Eif4a1 loci significantly delayed tumor onset. Lastly, tumors derived from Eif4e∆38 fs/+/Eμ-Myc or Eif4a1∆5 fs/+/Eμ-Myc mice show increased sensitivity to the chemotherapeutic agent doxorubicin, in vivo. Our study reveals that eIF4A2 and eIF4G3 play non-essential roles in gene expression regulation during embryogenesis; whereas reductions in eIF4E or eIF4A1 levels are protective against tumor development in a murine Myc-driven lymphoma setting.
- Published
- 2021