Natively Unfolded FG Repeats Stabilize the Structure of the Nuclear Pore Complex

Publication date: Available online 12 October 2017
Source:Cell
Author(s): Evgeny Onischenko, Jeffrey H. Tang, Kasper R. Andersen, Kevin E. Knockenhauer, Pascal Vallotton, Carina P. Derrer, Annemarie Kralt, Christopher F. Mugler, Leon Y. Chan, Thomas U. Schwartz, Karsten Weis
Nuclear pore complexes (NPCs) are ∼100 MDa transport channels assembled from multiple copies of ∼30 nucleoporins (Nups). One-third of these Nups contain phenylalanine-glycine (FG)-rich repeats, forming a diffusion barrier, which is selectively permeable for nuclear transport receptors that interact with these repeats. Here, we identify an additional function of FG repeats in the structure and biogenesis of the yeast NPC. We demonstrate that GLFG-containing FG repeats directly bind to multiple scaffold Nups in vitro and act as NPC-targeting determinants in vivo. Furthermore, we show that the GLFG repeats of Nup116 function in a redundant manner with Nup188, a nonessential scaffold Nup, to stabilize critical interactions within the NPC scaffold needed for late steps of NPC assembly. Our results reveal a previously unanticipated structural role for natively unfolded GLFG repeats as Velcro to link NPC subcomplexes and thus add a new layer of connections to current models of the NPC architecture.

Graphical abstract

Teaser

In addition to forming the permeability barrier, FG repeats in nucleoporins contribute structurally to nuclear pore biogenesis and function.


from # All Medicine by Alexandros G. Sfakianakis via Alexandros G.Sfakianakis on Inoreader http://ift.tt/2xD3pcY
via IFTTT