Incorporation of the nuclear pore basket protein Nup153 into nuclear pore structures is dependent upon lamina assembly: evidence from cell-free extracts of Xenopus eggs

• Published in: The EMBO journal 2000-08, Vol.19 (15), p.3918-3931
• Main Authors: Smythe, Carl, Jenkins, Hazel E., Hutchison, Christopher J.
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Animals; Carrier Proteins - metabolism; Cell-Free System; Conserved Sequence; Eggs; envelopes; Humans; Intermediate Filament Proteins - isolation & purification; Intermediate Filament Proteins - metabolism; Lamin Type B; nuclear envelope; Nuclear Envelope - metabolism; Nuclear Envelope - ultrastructure; nuclear lamina; nuclear pore complex; Nuclear Pore Complex Proteins; Nuclear Proteins - isolation & purification; Nuclear Proteins - metabolism; nucleoporins; Nup153; Nup153 protein; Ovum; Precipitin Tests; Protein Binding; Xenopus
• ISSN: 0261-4189; 1460-2075
• DOI: 10.1093/emboj/19.15.3918

In cell‐free extracts of Xenopus eggs that support the assembly of replication‐competent nuclei, we found that lamin B 3 specifically associates with four polypeptides (termed SLAPs, soluble lamin associated proteins). Here, one SLAP is identified as the nuclear pore complex protein Nup153, one member of the F/GXFG motif‐containing nucleoporins. In vitro translated Nup153 and lamin B 3 co‐immunoprecipitate, and lamin B 3 interacts specifically with the C‐terminal domain of Nup153. During nuclear envelope assembly, other F/GXFG‐containing nucleoporins are incorporated into the nuclear envelope preceding lamina assembly. Incorporation of Nup153 occurs at the same time as lamina assembly. When lamina assembly is prevented using the dominant‐negative mutant XlaminBΔ2+, Nup153 does not appear at the nuclear envelope, while other F/GXFG‐containing nucleoporins and Nup93 are recruited normally. When the lamina of pre‐assembled nuclei is disrupted using the same dominant‐negative mutant, the distribution of other nucleoporins is unaffected. However, Nup153 recruitment at the nuclear envelope is lost. Our results indicate that both the recruitment and maintenance of Nup153 at the pore are dependent upon the integrity of the lamina.