Translation initiation factors and active sites of protein synthesis co-localise at the leading edge of migrating MRC5 fibroblasts

Mark Willett , Michele Brocard , Alexandre Davide , Simon Morley (1)

1 Biochemistry

Cell migration is a highly controlled, essential cellular process often dys-regulated in tumour cells, dynamically controlled by the architecture of the cell. Studies involving cellular fractionation and microarray profiling have previously identified functionally distinct mRNA populations specific to cellular organelles and architectural compartments. However, the interaction between the translational machinery per se and cellular structures is relatively unexplored. To help understand the role for the compartmentalisation and localised protein synthesis in cell migration, we have used scanning confocal microscopy, immunofluorescence and a novel ribopuromycylation method to visualise translating ribosomes. Here we show that initiation factors (eIFs) localise to the leading edge of migrating MRC5 fibroblasts in a process dependent on trans-Golgi network (TGN) to plasma membrane vesicle transport. Here we show that eIF4E and eIF4GI are associated with the Golgi apparatus and membrane microdomains and that a proportion of these proteins co-localise to sites of active translation at the leading edge of migrating cells.

Mots clés: Life Sciences

Mark Willett, Michele Brocard, Alexandre Davide, Simon Morley. Translation initiation factors and active sites of protein synthesis co-localise at the leading edge of migrating MRC5 fibroblasts. Biochemical Journal, 2011, 438 (1), pp.217-227. ⟨10.1042/BJ20110435⟩. ⟨hal-00612969⟩