The eukaryotic translation initiation factor 3f (eIF3f) interacts physically with the alpha 1B-adrenergic receptor and stimulates adrenoceptor activity

Abstract

BackgroundeIF3f is a multifunctional protein capable of interacting with proteins involved in different cellular processes, such as protein synthesis, DNA repair, and viral mRNA edition. In human cells, eIF3f is related to cell cycle and proliferation, and its deregulation compromises cell viability.ResultsWe here report that, in native conditions, eIF3f physically interacts with the alpha 1B-adrenergic receptor, a plasma membrane protein considered as a proto-oncogene, and involved in vasoconstriction and cell proliferation. The complex formed by eIF3f and alpha 1B-ADR was found in human and mouse cell lines. Upon catecholamine stimulation, eIF3f promotes adrenoceptor activity in vitro, independently of the eIF3f proline- and alanine-rich N-terminal region.ConclusionsThe eIF3f/alpha adrenergic receptor interaction opens new insights regarding adrenoceptor-related transduction pathways and proliferation control in human cells. The eIf3f/alpha 1B-ADR complex is found in mammals and is not tissue specific.

Nuclear control of lung cancer cells migration, invasion and bioenergetics by eukaryotic translation initiation factor 3F

“…EIF3F was recently discovered in the nucleus of human cancer cells and was proposed to participate in DNA-related functions [7,8,13]. This localization is in agreement with EIF3F interactome analyses that revealed 20 EIF3Finteracting proteins located in the nucleus (Supplementary information Table S1).…”

“…These proteins are involved in the regulation of the cell cycle (GO:0007049), nuclear division (GO:0000280) and organelle organization (GO:0006996), as well as transcription-factor binding (GO:0001025), suggesting a possible nuclear role for EIF3F in the regulation of gene expression. Accordingly, Gutiérrez-Fernández et al [8] proposed that EIF3F has the ability to interact with different proteins located in the nucleus due to the presence of a Mpr1/Pad N-terminal motif that mediates protein-protein interactions and that promotes the assembly of large complexes. Therefore, we hypothesized that the participation of EIF3F in the cancer cells malignancy could involve unknown nuclear mechanisms that require partnering with unidentified proteins including genetic regulators of carcinogenesis.…”

eIF3f depletion impedes mouse embryonic development, reduces adult skeletal muscle mass and amplifies muscle loss during disuse

“…A gain in this factor causes apoptosis in proliferating cells and hypertrophy in differentiated muscle cells, whereas a loss causes malignancy in several cells and atrophy in differentiated muscle cells (Marchione et al 2013(Marchione et al , 2015Sanchez et al 2013). As reported previously for other eIF3 subunits, different interacting cofactors would explain a such discrepancy in eIF3f activity (Moretti et al 2010;Walter et al 2012;Wen et al 2012;Gutiérrez-Fernández et al 2015).…”