Séminaire Département de Biologie - Dr Felix WEIS

le 16 mars 2016 à 14h00

Felix WEIS, MRC Laboratory of Molecular Biology, Cambridge, UK.

Visualising late steps in cytoplasmic 60S subunit maturation

Ribosome biogenesis is a fundamental process that provides all living cells with
the protein synthesis machinery. Recent data indicate that defective ribosome
maturation predisposes to the development of human diseases including cancers.
Specifically, the nascent 60S ribosomal subunit undergoes an ordered series of
final maturation steps in the cytoplasm to become competent to enter translation,
including release of biogenesis factors, loading of ribosomal proteins and
acquisition of the mature conformation of the ribosomal RNA.

In particular, SBDS and the GTPase EFL1 cooperate to evict the anti-association
factor eIF6, while the release of the nuclear export factor Nmd3 by the GTPase
Lsg1 is coupled to uL16 incorporation. However, the underlying mechanisms and
timing of these two steps remain poorly understood.

Using the latest advances in single-particle cryo-electron microscopy, we have
visualised the structures of late pre-60S particles at subnanometre resolution. Our
data provide new insights into the mechanism and timing of eIF6 and Nmd3
release that is corrupted in leukaemia-associated ribosomopathies.

Lieu(x) : Ecole Polytechnique, Amphithéâtre Grégory

Contact : Yves Mechulam  (yves.mechulam at polytechnique.edu)