Encyclopedia of Signaling Molecules

2018 Edition
| Editors: Sangdun Choi

TIF5 (eIF5)

  • Umadas MaitraEmail author
  • Romit Majumdar
Reference work entry
DOI: https://doi.org/10.1007/978-3-319-67199-4_614


 Tif5p (in yeast)


The translation initiation process is mediated by a series of partial reactions each of which requires the participation of a large number of protein factors collectively called eukaryotic (translation) initiation factors (eIFs). The process leads to the assembly of an 80S ribosome-bound initiator Met-tRNAi at the start AUG codon of an mRNA that is active in peptidyl transfer. According to the currently accepted view of translation initiation, the first step is the binding of the initiator Met-tRNAi to the heterotrimeric GTP-binding initiation factor eIF2 to form the Met-tRNAi•eIF2•GTP ternary complex. The ternary complex then binds to the 40S ribosomal subunit containing bound initiation factor eIF3, a process that requires two other initiation factors eIF1 and eIF1A. This interaction leads to the formation of a 43S preinitiation complex (40S•eIF3•eIF1•eIF1A•Met-tRNAi•eIF2•GTP) which is then recruited to the 5′-capped end of the mRNA via...

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© Springer International Publishing AG 2018

Authors and Affiliations

  1. 1.Department of Developmental and Molecular BiologyAlbert Einstein College of Medicine of Yeshiva UniversityBronxUSA