Publications by authors named "Michael F Rexach"

Nuclear pore complexes (NPCs) gate the only conduits for nucleocytoplasmic transport in eukaryotes. Their gate is formed by nucleoporins containing large intrinsically disordered domains with multiple phenylalanine-glycine repeats (FG domains). In combination, these are hypothesized to form a structurally and chemically homogeneous network of random coils at the NPC center, which sorts macromolecules by size and hydrophobicity.

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The nuclear pore complex (NPC) provides the sole aqueous conduit for macromolecular exchange between the nucleus and the cytoplasm of cells. Its diffusion conduit contains a size-selective gate formed by a family of NPC proteins that feature large, natively unfolded domains with phenylalanine-glycine repeats (FG domains). These domains of nucleoporins play key roles in establishing the NPC permeability barrier, but little is known about their dynamic structure.

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A highly sensitive, equilibrium-based binding assay termed "Bead Halo" was used here to identify and characterize interactions involving components of the nucleocytoplasmic transport machinery in eukaryotes. Bead Halo uncovered novel interactions between the importin Kap95 and the nucleoporins (nups) Nic96, Pom34, Gle1, Ndc1, Nup84, and Seh1, which likely occur during nuclear pore complex biogenesis. Bead Halo was also used to characterize the molecular determinants for binding between Kap95 and the family of nups that feature multiple phenylalanine-glycine motifs (FG nups).

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Nuclear pore complexes (NPCs) form aqueous conduits in the nuclear envelope and gate the diffusion of large proteins between the cytoplasm and nucleoplasm. NPC proteins (nucleoporins) that contain phenylalanine-glycine motifs in filamentous, natively unfolded domains (FG domains) line the diffusion conduit of the NPC, but their role in the size-selective barrier is unclear. We show that deletion of individual FG domains in yeast relaxes the NPC permeability barrier.

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Nucleoporins with phenylalanine-glycine repeats (FG Nups) function at the nuclear pore complex (NPC) to facilitate nucleocytoplasmic transport. In Saccharomyces cerevisiae, each FG Nup contains a large natively unfolded domain that is punctuated by FG repeats. These FG repeats are surrounded by hydrophilic amino acids (AAs) common to disordered protein domains.

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The death of yeast treated with hydrogen peroxide (H(2)O(2)) shares a number of morphological and biochemical features with mammalian apoptosis. In this study, we report that the permeability of yeast nuclear envelopes (NE) increased during H(2)O(2)-induced cell death. Similar phenomena have been observed during apoptosis in mammalian tissue culture cells.

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