Schematic representation of the NUP98, smgGDS, NRG, and NRG2 proteins. Vertical arrowheads represent breakpoints in NUP98 and smgGDS. FG, FG (phenylalanine-glycine) repeat-rich areas; GLEBS, GLEBS (Gle2p-binding motif) -like motif48; NRM, nucleoporin RNA binding motif; ARMADILLO, tandem armadillo repeats.