Spelling out the roles of individual nucleoporins in nuclear export of mRNA

Abstract

The Nuclear Pore Complex (NPC) represents a critical passage through the nuclear envelope for nuclear import and export that impacts nearly every cellular process at some level. Recent technological advances in the form of Auxin Inducible Degron (AID) strategies and Single-Point Edge-Excitation sub-Diffraction (SPEED) microscopy have enabled us to provide new insight into the distinct functions and roles of nuclear basket nucleoporins (Nups) upon nuclear docking and export for mRNAs. In this paper, we provide a review of our recent findings as well as an assessment of new techniques, updated models, and future perspectives in the studies of mRNA’s nuclear export.

Obtaining 3D super-resolution images by utilizing rotationally symmetric structures and 2D-to-3D transformation

“…The degree of single-molecule localization error tolerable within the algorithm is directly correlated to the radius of the symmetrical structure being evaluated. For instance, a structure with a radius of 25 nm, the approximate radius of the central channel of the nuclear pore complex [51] , [52] , [53] , [54] , is only reproducible if the localization error remains below 21 nm. It is notable that the number of 21 nm is slightly smaller than the theoretical single-molecule localization error predicted by the Rayleigh criterion [55] .…”

Application of Super-resolution SPEED Microscopy in the Study of Cellular Dynamics

“…While the various karyopherins intersect in different fashions, they must all find a balance between strong enough interactions to allow for an association and weak enough to allow for complete transport. 39 An example of this is Importin 4, one of the transport receptors utilized for the import of histones and ribosomal proteins. 47 There is still discussion regarding the most accurate model to describe the behaviors of the NPC and how it regulates nucleocytoplasmic transport.…”

“…These karyopherins facilitate transport through the NPC by interacting with the hydrophobic FG-Nups. While the various karyopherins intersect in different fashions, they must all find a balance between strong enough interactions to allow for an association and weak enough to allow for complete transport . An example of this is Importin 4, one of the transport receptors utilized for the import of histones and ribosomal proteins …”

“…The gate required for these transport processes is the NPC, one of the cell’s largest and most complex protein structures, possessing a mass ranging from 66 to 125 MDa depending on the species . The NPC is composed of approximately 30 different, highly conserved proteins called nucleoporins (Nups). − These Nups are classified into three major categories: transmembrane, structural, and phenylalanine-glycine (FG) Nups.…”

A general method for quantitative fractionation of mammalian cells

“…The transport of molecules in and out of the nucleus is mediated by nuclear pore complexes (NPCs) embedded within the NE. A single NPC is composed of multiple copies of ∼30 different proteins, termed nucleoporins (Nups; Dultz et al, 2022 ; Stewart, 2022 ; Tingey et al, 2022 ; Wing et al, 2022 ), and is essential not only for nucleocytoplasmic trafficking but also for regulating genome organization and expression ( Simon and Rout, 2014 ; Tingey et al, 2022 ). Abnormal nucleocytoplasmic localization of proteins has been linked to pathogenesis of many human diseases, such as cancer, metabolic, cardiovascular, and neurodegenerative diseases ( Chung et al, 2018 ; Holmes et al, 2019 ; McLane and Corbett, 2009 ).…”