Figure 3.

SUN- and KASH-domain proteins interact in the NE lumen to form LINC (Links Nucleoskeleton and Cytoskeleton) complexes. SUN-domain proteins span the INM and dimerize; each nucleoplasmic domain binds lamins and each SUN-domain in the NE lumen binds the KASH domain of an ONM-embedded KASH protein, which binds actin, centrosomes/microtubules, or plectin/intermediate filaments in the cytoplasm. Only one KASH domain partner of a SUN dimer is depicted. SUN proteins also bind, potentially via Him-8, the pairing centers of meiotic chromosomes. Many additional nesprin isoforms reside elsewhere, including the INM; e.g., human nesprins-1α and -2β in the INM bind lamins and emerin (not shown).