Multi-isomeric modular protein which forms a linking network between organelles and the actin cytoskeleton to maintain the subcellular spatial organization. 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. May be involved in nucleus-centrosome attachment and nuclear migration in neural progenitors implicating LINC complex association with SUN1/2 and probably association with cytoplasmic dynein-dynactin motor complexes; SYNE1 and SYNE2 may act redundantly. Required for centrosome migration to the apical cell surface during early ciliogenesis. May be involved in nuclear remodeling during sperm head formation in spermatogenesis; a probable SUN3:SYNE1/KASH1 LINC complex may tether spermatid nuclei to posterior cytoskeletal structures such as the manchette. Core component of LINC complexes which are composed of inner nuclear membrane SUN domain-containing proteins coupled to outer nuclear membrane KASH domain-containing nesprins. SUN and KASH domain-containing proteins seem to bind each other promiscuously; however, differentially expression of LINC complex constituents can give rise to specific assemblies. At least SUN1/2-containing core LINC complexes are proposed to be hexameric composed of three protomers of each KASH and SUN domain-containing protein. The SUN2:SYNE1/KASH1 LINC complex is a heterohexamer; the homotrimeric cloverleave-like conformation of the SUN domain is a prerequisite for LINC complex formation in which three separate SYNE1/KASH1 peptides bind at the interface of adjacent SUN domains. Self-associates. Interacts with SYNE3. Interacts with SPAG4/SUN4. May interact with MUSK. Interacts with F-actin via its N-terminal domain. Interacts with EMD and LMNA in vitro. Interacts (via KASH domain) with TMEM258 (PubMed:28716842). The largest part of the protein is cytoplasmic, while its C-terminal part is associated with the nuclear envelope, most probably the outer nuclear membrane. In skeletal and smooth muscles, a significant amount is found in the sarcomeres. In myoblasts, relocalized from the nuclear envelope to the nucleus and cytoplasm during cell differentiation. Expressed in HeLa, A431, A172 and HaCaT cells (at protein level). Widely expressed. Highly expressed in skeletal and smooth muscles, heart, spleen, peripheral blood leukocytes, pancreas, cerebellum, stomach, kidney and placenta. Isoform GSRP-56 is predominantly expressed in heart and skeletal muscle (at protein level). The KASH domain, which contains a transmembrane domain, mediates the nuclear envelope targeting and is involved in the binding to SUN1 and SUN2 through recognition of their SUN domains. The disulfid bond with SUN1 or SUN2 is required for stability of the respective LINC complex under tensile forces. The disease is caused by variants affecting the gene represented in this entry. The disease is caused by variants affecting the gene represented in this entry. The disease is caused by variants affecting the gene represented in this entry. Lost in uterus, cervix, kidney, lung, thyroid and pancreas carcinomas, already at early tumor stages. Muscle-specific. Interacts with TRPV2. Belongs to the nesprin family. Truncated N-terminus. Extended N-terminus. Contaminating sequence. Sequence of unknown origin. Chimeric cDNA. Truncated N-terminus. Truncated N-terminus. Enaptin entry