Feb 25, 2011

Lumenal interactions in nuclear pore complex assembly and stability

Molecular Biology of the Cell
William T YewdellC Patrick Lusk

Abstract

Nuclear pore complexes (NPCs) provide a gateway for the selective transport of macromolecules across the nuclear envelope (NE). Although we have a solid understanding of NPC composition and structure, we do not have a clear grasp of the mechanism of NPC assembly. Here, we demonstrate specific defects in nucleoporin distribution in strains lacking Heh1p and Heh2p-two conserved members of the LEM (Lap2, emerin, MAN1) family of integral inner nuclear membrane proteins. These effects on nucleoporin localization are likely of functional importance as we have defined specific genetic interaction networks between HEH1 and HEH2, and genes encoding nucleoporins in the membrane, inner, and outer ring complexes of the NPC. Interestingly, expression of a domain of Heh1p that resides in the NE lumen is sufficient to suppress both the nucleoporin mislocalization and growth defects in heh1Δpom34Δ strains. We further demonstrate a specific physical interaction between the Heh1p lumenal domain and the massive cadherin-like lumenal domain of the membrane nucleoporin Pom152p. These findings support a role for Heh1p in the assembly or stability of the NPC, potentially through the formation of a lumenal bridge with Pom152p.

  • References84
  • Citations32

References

Mentioned in this Paper

Saccharomyces cerevisiae Proteins
Establishment and Maintenance of Localization
TMPO gene
Entire Lumen of Body System
Complex (molecular entity)
Tertiary Protein Structure
ERBB2IP gene
HSP90AA1 gene
Sequence Determinations
EMD gene

Related Feeds

Cadherins and Catenins

Cadherins (named for "calcium-dependent adhesion") are a type of cell adhesion molecule (CAM) that is important in the formation of adherens junctions to bind cells with each other. Catenins are a family of proteins found in complexes with cadherin cell adhesion molecules of animal cells: alpha-catenin can bind to β-catenin and can also bind actin. β-catenin binds the cytoplasmic domain of some cadherins. Discover the latest research on cadherins and catenins here.

Adherens Junctions

An adherens junction is defined as a cell junction whose cytoplasmic face is linked to the actin cytoskeleton. They can appear as bands encircling the cell (zonula adherens) or as spots of attachment to the extracellular matrix (adhesion plaques). Adherens junctions uniquely disassemble in uterine epithelial cells to allow the blastocyst to penetrate between epithelial cells. Discover the latest research on adherens junctions here.

Adhesion Molecules in Health and Disease

Cell adhesion molecules are a subset of cell adhesion proteins located on the cell surface involved in binding with other cells or with the extracellular matrix in the process called cell adhesion. In essence, cell adhesion molecules help cells stick to each other and to their surroundings. Cell adhesion is a crucial component in maintaining tissue structure and function. Discover the latest research on adhesion molecule and their role in health and disease here.