Plant SUN domain proteins

We have recently reported the identification and characterization of Sad1/UNC84 (SUN) domain proteins in various plant species. In animals and yeasts, SUN domain proteins are localized at the inner nuclear membrane and form a bridge across the nuclear envelope (NE) by interacting with outer nuclear membrane-localized Klarsicht/Anc-1/Syne-1 homology (KASH) domain proteins. This bridge physically connects cytoskeletal elements with chromatin and nucleoskeletal components. These multiprotein complexes are essential for various cellular and nuclear processes. The identification of SUN domain proteins provides the first evidence of putative NE bridging complexes in plants. Here we speculate on the composition and functions of these in regards to our current understanding of plant SUN domain proteins.