LINC complexes are formed by coupling of KASH (Klarsicht, ANC-1, and Syne/Nesprin Homology) and SUN (Sad1 and UNC-84) proteins from the inner and outer nuclear membranes (INM and ONM, respectively). the formation of LINC complexes by KASH and SUN proteins at the nuclear envelope (NE) establishes the physical linkage between the cytoskeleton and nuclear lamina, which is instrumental for the mechanical force transmission from the cytoplasm to the nuclear interior, and is essential for cellular processes such as nuclear positioning and migration, centrosome-nucleus anchorage, and chromosome dynamics. This entry represents an HTH domain found in SUN2 that forms a three-helix bundle to lock the SUN domain in an inactive conformation acting as an inhibitory component.

1: Coiled-Coil Domains of SUN Proteins as Intrinsic Dynamic Regulators. Nie S, Ke H, Gao F, Ren J, Wang M, Huo L, Gong W, Feng W; Structure. 2016;24:80-91. PMID:26688217

2: Structure of Sad1-UNC84 homology (SUN) domain defines features of molecular bridge in nuclear envelope. Zhou Z, Du X, Cai Z, Song X, Zhang H, Mizuno T, Suzuki E, Yee MR, Berezov A, Murali R, Wu SL, Karger BL, Greene MI, Wang Q; J Biol Chem. 2012;287:5317-5326. PMID:22170055