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The nuclear pore complex (NPC) proteins (nucleoporins), Nic96p and Nup188p, are essential for normal formation of the NPC. Mutations in the Nic96p central domain block NPC formation at nonpermissive temperatures and decrease the density of the nuclear pore. Nic96p is functionally and physically linked to the Nup188p nucleoporin. Nup188p is linked to the carboxy-terminal and central domain of Nic96p. Mutations in Nup188p produce the nuclear envelope blistering phenotype due to the formation of seals over the NPC.

Nsp1p associates with the various nuclear pore complex (NPC) structures and is involved in multiple interactions at the NPC. The carboxy-terminal domain demonstrating heptad repeats of the nuclear pore protein, Nup82, binds to Nsp1p. In yeast cells where Nup82p is absent, cell growth is inhibited and a disorder is observed in the poly(A)+ RNA export.

Nup145p, Nup116p and Nup100p belong to a new class of nucleoporins that are involved in macromolecular transport. Nup145p, a yeast protein containing GLFG repeat sequences, is required for poly (A)+ RNA transport from the nucleus. Repression of Nup145p gene pronin results in nuclear accumulation of polyadenylated RNAs and cytoplasmic localization of a nuclear transporter protein.

Temperature-sensitive lethal point mutations were generated in the NOP1 yeast gene, which codes for a small nucleolar (sno) RNA-associated protein homologous to fibrillarin. Analysis of the mutations' effects on ribosome synthesis showed that NOP1 is involved in the cleavage of pre-rRNAs, methylation and pseudouuridylation of the rRNAs and assembly of the rRNAs with ribosomal proteins. It is proposed that NOP1 is required for pre-rRNA to adopt the correct conformation in order to undergo these various steps in ribosome synthesis.

A new preparation protocol for electron microscopy samples facilitated the structural analysis of yeast nuclear pore complexes (NPCs). Findings revealed that yeasts NPCs are organized based on an architecture similar to vertebrate NPCs. The study confirmed the presence of cytoplasmic fibrils and a nuclear basket within the yeast NPC. Although yeast and Xenopus NPCs have similar structural organizations, the former were found to be 15% smaller in linear dimensions, indicating that its architecture is evolutionary conserved. NSp1p, along with its interacting partners, was localized and found to reside in three subcomplexes.