SUN2

SUN2 (Sad1 And UNC84 Domain Containing 2) is a protein coding gene. Diseases associated with SUN2 include Emery-Dreifuss Muscular Dystrophy and Emerinopathy. Among its related pathways are Cell Cycle, Mitotic and Meiosis. Gene Ontology annotations related to this gene include identical protein binding and lamin binding. An important paralog of this gene is SUN1.

Full Name

Sad1 And UNC84 Domain Containing 2

Function

As a component of the LINC (LInker of Nucleoskeleton and Cytoskeleton) complex, involved in the connection between the nuclear lamina and the cytoskeleton. The nucleocytoplasmic interactions established by the LINC complex play an important role in the transmission of mechanical forces across the nuclear envelope and in nuclear movement and positioning. Specifically, SYNE2 and SUN2 assemble in arrays of transmembrane actin-associated nuclear (TAN) lines which are bound to F-actin cables and couple the nucleus to retrograde actin flow during actin-dependent nuclear movement. Required for interkinetic nuclear migration (INM) and essential for nucleokinesis and centrosome-nucleus coupling during radial neuronal migration in the cerebral cortex and during glial migration. Required for nuclear migration in retinal photoreceptor progenitors implicating association with cytoplasmic dynein-dynactin and kinesin motor complexes, and probably B-type lamins; SUN1 and SUN2 seem to act redundantly. The SUN1/2:KASH5 LINC complex couples telomeres to microtubules during meiosis; SUN1 and SUN2 seem to act at least partial redundantly. Anchors chromosome movement in the prophase of meiosis and is involved in selective gene expression of coding and non-coding RNAs needed for gametogenesis. Required for telomere attachment to nuclear envelope and gametogenesis. May also function on endocytic vesicles as a receptor for RAB5-GDP and participate in the activation of RAB5.

Biological Process

Biological Process centrosome localizationISS:UniProtKB
Biological Process meiotic cell cycleIEA:UniProtKB-KW
Biological Process mitotic spindle organizationManual Assertion Based On ExperimentTAS:UniProtKB
Biological Process nuclear envelope organizationManual Assertion Based On ExperimentIGI:MGI
Biological Process nuclear matrix anchoring at nuclear membraneManual Assertion Based On ExperimentIDA:UniProtKB
Biological Process nuclear migrationManual Assertion Based On ExperimentTAS:UniProtKB
Biological Process nuclear migration along microfilamentISS:UniProtKB
Biological Process positive regulation of cell migrationISS:UniProtKB

Cellular Location

Nucleus inner membrane
Nucleus envelope
Endosome membrane

Topology

Nuclear: 1-212
Helical: 213-233
Perinuclear space: 234-717

PTM

The disulfide bond with SYNE2 is required for stability of the SUN2:SYNE2/KASH2 LINC complex under tensile forces though not required for the interaction. The disulfide bond is proposed to be conserved in LINC complexes involved in force transmission.