SUN1 (MIM 607723) and SUN2 are inner nuclear membrane (INM) proteins that play a major role in nuclear-cytoplasmic connection by formation of a 'bridge' across the nuclear envelope, known as the LINC complex, via interaction with the conserved luminal KASH domain of nesprins (e.g., SYNE1\; MIM 608441) located in the outer nuclear membrane (ONM). The LINC complex provides a direct connection between the nuclear lamina and the cytoskeleton, which contributes to nuclear positioning and cellular rigidity (summary by Haque et al., 2010 [PubMed 19933576]).[supplied by OMIM, Nov 2010].
Borrego-Pinto, Jegou, Osorio, Auradé, Gorjánácz, Koch, Mattaj, Gomes: "Samp1 is a component of TAN lines and is required for nuclear movement." in: Journal of cell science, Vol. 125, Issue Pt 5, pp. 1099-105, (2012) (PubMed).
Haque, Mazzeo, Patel, Smallwood, Ellis, Shanahan, Shackleton: "Mammalian SUN protein interaction networks at the inner nuclear membrane and their role in laminopathy disease processes." in: The Journal of biological chemistry, Vol. 285, Issue 5, pp. 3487-98, (2010) (PubMed).