NUMA1
NUMA1 (nuclear mitotic apparatus protein 1, also known as NUMA) is a large microtubule-binding protein that organises the spindle poles during mitosis. It is also a highly abundant structural component of the nuclear matrix in interphase cells. Browse Assay Genie's current range of NUMA1 research reagents below, or read on for the biology behind the target.
NUMA1 binds microtubules and plays a role in the formation and maintenance of the spindle poles, and in the alignment and segregation of chromosomes during mitotic cell division. It tethers the minus ends of microtubules at the spindle poles, which is critical for establishing and maintaining them. It also contributes to mitotic microtubule aster assembly and to anastral spindle assembly.
The protein also sets spindle orientation. In metaphase it forms part of a ternary complex with GPSM2 and G(i) alpha proteins. This complex regulates the recruitment and anchorage of the dynein-dynactin complex at the mitotic cell cortex above the two spindle poles. In anaphase, NUMA1 associates directly with phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) at the cell membrane of the polar cortical region. This recruits dynein-dynactin and helps regulate spindle elongation and chromosome segregation. In vitro it also binds other polyanionic phosphoinositides, including PIP, LPA and PIP3. NUMA1 is needed for correct spindle orientation in asymmetric cell divisions, and it positively regulates TNKS localisation to spindle poles in mitosis.
Outside mitosis, NUMA1 is a highly abundant component of the nuclear matrix and occupies most of the nuclear volume, where it may have a non-mitotic structural role. UniProt annotates it as required for epidermal differentiation and hair follicle morphogenesis. Its localisation spans the nucleus, centrosome, spindle pole, cell cortex and lateral cell membrane. The NUMA1 gene is the source of multiple transcript variants through alternative splicing. Chromosomal translocation between NUMA1 and the RARA (retinoic acid receptor alpha) gene has been detected in patients with acute promyelocytic leukaemia.
NUMA1 tethers microtubule minus ends at spindle poles, making it central to spindle pole formation and chromosome alignment and segregation.
With GPSM2, G(i) alpha and dynein-dynactin, NUMA1 anchors force generators at the cell cortex to orient the spindle.
NUMA1 is a highly abundant nuclear matrix component that occupies most of the nuclear volume and may have a structural role.
A NUMA1–RARA translocation has been detected in patients with acute promyelocytic leukaemia, linking the gene to disease research.
NUMA1 is a microtubule-binding protein that tethers microtubule minus ends at the spindle poles, supporting spindle pole formation, chromosome alignment and segregation. It also helps orient the mitotic spindle through dynein-dynactin, and acts as a structural component of the nuclear matrix outside mitosis.
The HGNC-approved name is nuclear mitotic apparatus protein 1, and NUMA is a recognised alias. The gene undergoes alternative splicing, which gives multiple transcript variants. Researchers searching for the NUMA1 gene or NUMA1 protein may therefore find either name in the literature.
Chromosomal translocation of NUMA1 with the RARA gene has been detected in patients with acute promyelocytic leukaemia. A mouse ortholog, Numa1, exists. Check the datasheet of any product for its validated reactivity.
Spindle orientation partners, translocation partners and mitotic regulators related to NUMA1 with products at Assay Genie.
Gene and protein annotations from HGNC, NCBI Gene and UniProt Q14980; product specifications from Assay Genie datasheets.