SUN2
Description
The SUN2 (Sad1 and UNC84 domain containing 2) is a protein-coding gene located on chromosome 22.
SUN2 is a protein that plays a crucial role in the connection between the nuclear lamina and the cytoskeleton. This connection, facilitated by the LINC complex, is essential for transmitting mechanical forces across the nuclear envelope, influencing nuclear movement and positioning. SUN2 is involved in various processes including nuclear migration during development, telomere attachment to microtubules during meiosis, and selective gene expression. It also has a potential role in endocytosis through interaction with RAB5.
SUN2, as a component of the LINC complex, plays a crucial role in connecting the nuclear lamina to the cytoskeleton. This connection facilitates the transmission of mechanical forces across the nuclear envelope, ultimately influencing nuclear movement and positioning. Specifically, SUN2, alongside SYNE2, forms arrays of TAN lines which bind to F-actin cables. This interaction couples the nucleus to retrograde actin flow, impacting actin-dependent nuclear movement. SUN2 is essential for INM, nucleokinesis, and centrosome-nucleus coupling during neuronal and glial migration. It is involved in nuclear migration in retinal photoreceptor progenitors, likely associating with cytoplasmic dynein-dynactin and kinesin motor complexes. SUN2 also contributes to telomere attachment to microtubules during meiosis, potentially through the SUN1/2:KASH5 LINC complex. SUN2 anchors chromosome movement during prophase of meiosis and is involved in the selective gene expression of coding and non-coding RNAs essential for gametogenesis. It is required for telomere attachment to the nuclear envelope and gametogenesis. Additionally, SUN2 may act as a receptor for RAB5-GDP on endocytic vesicles, contributing to the activation of RAB5.
SUN2 is also known as UNC84B, rab5IP.
