SUN1

This gene is a member of the unc-84 homolog family and encodes a nuclear nuclear envelope protein with an Unc84 (SUN) domain. The protein is involved in nuclear anchorage and migration. Alternatively spliced transcript variants have been described.

Full Name

Sad1 and UNC84 domain containing 1

Function

As a component of the LINC (LInker of Nucleoskeleton and Cytoskeleton) complex involved in the connection between the nuclear lamina and the cytoskeleton (PubMed:18039933, PubMed:18396275).
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 (By similarity).
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 (By similarity).
Involved in telomere attachment to nuclear envelope in the prophase of meiosis implicating a SUN1/2:KASH5 LINC complex in which SUN1 and SUN2 seem to act at least partial redundantly (By similarity).
Required for gametogenesis and involved in selective gene expression of coding and non-coding RNAs needed for gametogenesis (By similarity).
Helps to define the distribution of nuclear pore complexes (NPCs) (By similarity).
Required for efficient localization of SYNE4 in the nuclear envelope (By similarity).
May be involved in nuclear remodeling during sperm head formation in spermatogenesis (By similarity).
May play a role in DNA repair by suppressing non-homologous end joining repair to facilitate the repair of DNA cross-links (PubMed:24375709).

Biological Process

Biological Process centrosome localizationIEA:Ensembl
Biological Process homologous chromosome pairing at meiosisIEA:Ensembl
Biological Process meiotic attachment of telomere to nuclear envelopeIEA:Ensembl
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 nucleokinesis involved in cell motility in cerebral cortex radial glia guided migrationIEA:Ensembl
Biological Process spermatogenesisIEA:UniProtKB-KW

Cellular Location

Nucleus inner membrane
At oocyte MI stage localized around the spindle, at MII stage localized to the spindle poles.

Topology

Nuclear: 1-288
Helical: 289-308
Perinuclear space: 309-785

PTM

The disulfide bond with KASH domain-containing nesprins is required for stability of the respective LINC complexes under tensile forces.