EIF3S5 Protein, Human (GST)

EIF3S5 protein functions as a vital component of the eukaryotic translation initiation factor 3 (eIF-3) complex, crucial for multiple stages in protein synthesis initiation. This complex associates with the 40S ribosome, facilitating the recruitment of essential factors to form the 43S pre-initiation complex (43S PIC). EIF3S5 within the eIF-3 complex plays a key role in stimulating mRNA recruitment to the 43S PIC and scanning the mRNA for AUG recognition. Additionally, the eIF-3 complex, including EIF3S5, is essential for the disassembly and recycling of post-termination ribosomal complexes, preventing premature joining of the 40S and 60S ribosomal subunits before initiation. Notably, the eIF-3 complex, with EIF3S5 as a component, selectively targets and initiates the translation of a specific subset of mRNAs related to cell proliferation, including those involved in cell cycling, differentiation, and apoptosis. EIF3S5 also exhibits deubiquitinating activity on activated NOTCH1, promoting its nuclear import and thereby acting as a positive regulator of Notch signaling. These diverse functions underscore the critical role of EIF3S5 in coordinating translational initiation and cellular processes with implications for Notch signaling regulation.