Figure 1.

nmd3ΔC14 is trapped in the nucleus and impairs 60S subunit export. (A) Wild-type (WT) and nmd3ΔC14 strains were cultured in YPD to midlog phase and subjected to indirect immunofluorescence for visualization of endogenous Nmd3 localization. The effect of nmd3ΔC14 on nuclear export of the 60S subunit was monitored by Rpl25-eGFP. The nmd3l505a allele has an effect similar to that of nmd3ΔC14 on blocking nuclear export of the 60S subunit, as monitored by Rpl25-eGFP. (B) Cartoon of the primary structure of Nmd3. CC: Cys-x₂-Cys repeats that comprise zinc-binding motifs. Dark gray indicate regions to which mutations that disrupt 60S binding map (Hedges et al., 2006). Amino acid sequence of the C-terminus of Nmd3 with the residues deleted in the nmd3ΔC14 mutant shown in light gray. An alignment of NESs of Nmd3 from various organisms is shown. The canonical leucine-rich NES sequence is shown with two examples from PKI and HIV-1 Rev. (Φ, hydrophobic residues (L,M,I,V); X, any amino acid). Gray bars highlight conserved residues. Sc, S. cerevisiae; Dm, Drosophila melanogaster; and Hs, Homo sapiens. Numbers indicate amino acid positions.