SUN2
SUN2 (Sad1 and UNC84 domain containing 2, also known as UNC84B) is an inner nuclear membrane protein and a component of the LINC complex. It connects the nuclear lamina to the cytoskeleton and helps transmit mechanical force across the nuclear envelope. Browse Assay Genie's current range of SUN2 research reagents below, or read on for the biology behind the target.
SUN2 is an inner nuclear membrane protein that forms part of the LINC (LInker of Nucleoskeleton and Cytoskeleton) complex. By interacting with the luminal KASH domain of nesprins in the outer nuclear membrane, such as SYNE1, it forms a bridge across the nuclear envelope. This gives a direct connection between the nuclear lamina and the cytoskeleton, and contributes to nuclear positioning and cellular rigidity. The complex transmits mechanical forces across the nuclear envelope and supports nuclear movement.
In one well-described arrangement, SYNE2 and SUN2 assemble into arrays called transmembrane actin-associated nuclear (TAN) lines. These bind F-actin cables and couple the nucleus to retrograde actin flow during actin-dependent nuclear movement. SUN2 is required for interkinetic nuclear migration and is essential for nucleokinesis and centrosome-nucleus coupling during radial neuronal migration in the cerebral cortex and during glial migration. It is also needed for nuclear migration in retinal photoreceptor progenitors, which implicates cytoplasmic dynein-dynactin and kinesin motor complexes and probably B-type lamins. SUN1 and SUN2 appear to act redundantly in these settings.
In meiosis, the SUN1/2:KASH5 LINC complex couples telomeres to microtubules, anchors chromosome movement in prophase and is required for telomere attachment to the nuclear envelope and for gametogenesis. SUN2 is also involved in selective expression of coding and non-coding RNAs needed for gametogenesis. It may also act on endocytic vesicles as a receptor for RAB5-GDP and take part in RAB5 activation. The SUN2 gene belongs to the SUN family, was formerly named unc-84 homolog B (C. elegans), and has a mouse ortholog, Sun2.
SUN2 is a LINC complex component that transmits mechanical forces across the nuclear envelope, making it central to studies of nucleus-cytoskeleton coupling.
SUN2 supports nuclear movement, interkinetic nuclear migration and nucleokinesis in neuronal, glial and retinal photoreceptor progenitor cells.
With KASH5, SUN2 couples telomeres to microtubules and attaches them to the nuclear envelope, which is required for gametogenesis.
SUN2 may act on endocytic vesicles as a receptor for RAB5-GDP and take part in RAB5 activation.
SUN2 is an inner nuclear membrane protein in the LINC complex. It links the nuclear lamina to the cytoskeleton through nesprins, helping to transmit mechanical force, position the nucleus and move it during cell migration. It also anchors telomeres during meiosis.
SUN2 is also known as UNC84B, and its HGNC full name is Sad1 and UNC84 domain containing 2. UniProt calls the protein SUN domain-containing protein 2. A previous gene name was unc-84 homolog B (C. elegans).
SUN1 and SUN2 are both inner nuclear membrane proteins that form LINC complexes with nesprins. In nuclear migration in photoreceptor progenitors and in meiotic telomere coupling, they seem to act redundantly or at least partly redundantly. SUN2 has a mouse ortholog, Sun2.
Other SUN family proteins and LINC complex components with research reagents at Assay Genie.
Gene and protein annotations from HGNC, NCBI Gene and UniProt Q9UH99; product specifications from Assay Genie datasheets.