title: Evolutionarily Conserved Sequence Features Regulate the Formation of the FG Network at the Center of the Nuclear Pore Complex.
abstract: The nuclear pore complex (NPC) is the portal for bidirectional transportation of cargos between the nucleus and the cytoplasm. While most of the structural elements of the NPC, i.e. nucleoporins (Nups), are well characterized, the exact transport mechanism is still under much debate. Many of the functional Nups are rich in phenylalanine-glycine (FG) repeats and are believed to play the key role in nucleocytoplasmic transport. We present a bioinformatics study conducted on more than a thousand FG Nups across 252 species. Our results reveal the regulatory role of polar residues and specific sequences of charged residues, named 'like charge regions' (LCRs), in the formation of the FG network at the center of the NPC. Positively charged LCRs prepare the environment for negatively charged cargo complexes and regulate the size of the FG network. The low number density of charged residues in these regions prevents FG domains from forming a relaxed coil structure. Our results highlight the significant role of polar interactions in FG network formation at the center of the NPC and demonstrate that the specific localization of LCRs, FG motifs, charged, and polar residues regulate the formation of the FG network at the center of the NPC.
authors.affiliation: Molecular Cell Biomechanics Laboratory, Departments of Bioengineering and Mechanical Engineering, University of California, Berkeley, CA 94720.
authors.forename: M
authors.initials: M
authors.lastname: Peyro
authors.affiliation: Molecular Cell Biomechanics Laboratory, Departments of Bioengineering and Mechanical Engineering, University of California, Berkeley, CA 94720.
authors.forename: M
authors.initials: M
authors.lastname: Soheilypour
authors.affiliation: Molecular Cell Biomechanics Laboratory, Departments of Bioengineering and Mechanical Engineering, University of California, Berkeley, CA 94720.
authors.forename: B L
authors.initials: BL
authors.lastname: Lee
authors.affiliation: Molecular Cell Biomechanics Laboratory, Departments of Bioengineering and Mechanical Engineering, University of California, Berkeley, CA 94720.
authors.forename: M R K
authors.initials: MR
authors.lastname: Mofrad
mesh_terms: D021581:Active Transport, Cell Nucleus / Q000235:genetics; D005075:Biological Evolution; D002467:Cell Nucleus / Q000235:genetics / Q000378:metabolism; D019295:Computational Biology / Q000379:methods; D017124:Conserved Sequence / Q000235:genetics*; D003593:Cytoplasm / Q000235:genetics / Q000378:metabolism; D005998:Glycine / Q000378:metabolism*; D022022:Nuclear Pore / Q000235:genetics* / Q000378:metabolism*; D028861:Nuclear Pore Complex Proteins / Q000378:metabolism*; D010649:Phenylalanine / Q000378:metabolism*; D017434:Protein Structure, Tertiary
chemical_list: D028861:Nuclear Pore Complex Proteins; D010649:Phenylalanine; D005998:Glycine