Fig. 1: Structural characterization of the snRNA export complex.
From: Structural basis for the synergistic assembly of the snRNA export complex
a, Schematic representation of the PHAX domain structure. The positions of the ARS2 (ARM) and CBC-binding regions (W118) are shown. b, A schematic model of snRNA export mediated by the snRNA export complex assembled in the nucleus and disassembled in the cytoplasm. c,d, The Superdex 200 gel filtration elution profile (c) and SDS-PAGE analysis (d) of fractions 1–12 of the snRNA complex reconstituted with capped U1 snRNA. The five proteins co-elute in the first peak highlighted with the red rectangle in d. L, input sample loaded onto the column; M, Mw marker. e, Overlay of Superdex 200 gel filtration elution profiles of the snRNA complex reconstitutions with a short capped 14-nt RNA using phosphorylated (P-PHAX) or unmodified PHAX. The complex elutes in fractions highlighted in red. f,g, SDS-PAGE analysis of fractions 1–12 of the gel filtration elution profiles shown in e using P-PHAX (f) and unmodified PHAX (g). The red rectangle shows fractions containing the snRNA export complex. In g, the complex formation is less efficient and CBC co-elutes mostly with PHAX in fractions 8 and 9. h, The cryo-EM map used to build the snRNA export complex structure containing a 14-nt capped RNA. The map is colored according to the molecules location in the structure: CBP80 is in light blue, CBP20 in blue, capped RNA in gray, PHAX in dark brick, CRM1 in yellow and Ran in violet. i, Ribbon representation of the snRNA export complex. RNA and GTP are shown as sticks.
