Journal Article

Structural and functional analysis of mRNA export regulation by the nuclear pore complex

Lin, Daniel H., Jette, Claudia A., Correia, Ana R., Cai, Sarah W., Hoelz, André, Huber, Ferdinand M.

2018

Overview

The nuclear pore complex (NPC) controls the passage of macromolecules between the nucleus and cytoplasm, but how the NPC directly participates in macromolecular transport remains poorly understood. In the final step of mRNA export, the DEAD-box helicase DDX19 is activated by the nucleoporins Gle1, Nup214, and Nup42 to remove Nxf1•Nxt1 from mRNAs. Here, we report crystal structures of Gle1•Nup42 from three organisms that reveal an evolutionarily conserved binding mode. Biochemical reconstitution of the DDX19 ATPase cycle establishes that human DDX19 activation does not require IP 6 , unlike its fungal homologs, and that Gle1 stability affects DDX19 activation. Mutations linked to motor neuron diseases cause decreased Gle1 thermostability, implicating nucleoporin misfolding as a disease determinant. Crystal structures of human Gle1•Nup42•DDX19 reveal the structural rearrangements in DDX19 from an auto-inhibited to an RNA-binding competent state. Together, our results provide the foundation for further mechanistic analyses of mRNA export in humans. The export of mRNA to the cytosol depends on the nuclear pore complex (NPC) and the activation of the helicase DDX19, but their interplay in humans remains poorly understood. Here, the authors present a structural and functional analysis of DDX19 activation, revealing how the human NPC regulates mRNA export.

• Publisher: Nature Publishing Group UK,Nature Publishing Group,Nature Portfolio
• Subject: 14/63 / 631/378/1689/364 / 631/45/535/1266 / 631/80/389/2029 / 631/80/389/2052 / 82/16 / 82/29 / 82/80 / 82/83 / Activation / Active Transport, Cell Nucleus / Adenosine triphosphatase / Binding / Chaetomium - genetics / Chaetomium - metabolism / Crystal structure / Cytoplasm / DEAD-box RNA Helicases - chemistry / DEAD-box RNA Helicases - genetics / DEAD-box RNA Helicases - metabolism / DNA helicase / Exports / Functional analysis / Fungal Proteins - chemistry / Fungal Proteins - genetics / Fungal Proteins - metabolism / Homology / Humanities and Social Sciences / Humans / Macromolecules / Models, Biological / Models, Molecular / mRNA / multidisciplinary / Mutation / Nuclear Pore - chemistry / Nuclear Pore - genetics / Nuclear Pore - metabolism / Nuclear Pore Complex Proteins - chemistry / Nuclear Pore Complex Proteins - genetics / Nuclear Pore Complex Proteins - metabolism / Nucleocytoplasmic Transport Proteins - chemistry / Nucleocytoplasmic Transport Proteins - genetics / Nucleocytoplasmic Transport Proteins - metabolism / Nucleoporins / Phytic Acid - metabolism / Recombinant Proteins - chemistry / Recombinant Proteins - genetics / Recombinant Proteins - metabolism / Ribonucleic acid / RNA / RNA Transport / RNA, Messenger - chemistry / RNA, Messenger - genetics / RNA, Messenger - metabolism / Saccharomyces cerevisiae - genetics / Saccharomyces cerevisiae - metabolism / Saccharomyces cerevisiae Proteins - chemistry / Saccharomyces cerevisiae Proteins - genetics / Saccharomyces cerevisiae Proteins - metabolism / Science / Science (multidisciplinary) / Structure-function relationships / Thermal stability