Ninein - Centrosome Marker Antibody - #DF13256

Centrosomal protein required in the positioning and anchorage of the microtubule minus-end in epithelial cells. May also act as a centrosome maturation factor. May play a role in microtubule nucleation, by recruiting the gamma-tubulin ring complex to the centrosome. Overexpression does not perturb nucleation or elongation of microtubules but suppresses release of microtubules. Required for centriole organization and microtubule anchoring at the mother centriole.

Phosphorylated by AURKA/Aurora kinase A and PKA kinases but not CK2 or AURKB/ Aurora kinase B.

Cytoplasm>Cytoskeleton>Microtubule organizing center>Centrosome. Cytoplasm>Cytoskeleton>Microtubule organizing center>Centrosome>Centriole.
Note: Component of the core centrosome. Arranged in a tubular conformation with an open and a closed end within the centrosome. In the mother centrosome, it localizes at both ends of the centrosome tube, including the site of centrosome duplication, while in the daughter centrosome it is present only at the closed end. Requires PCM1 for centrosome localization. Localizes to the subdistal appendage region of the centriole in a DCTN1-dependent manner.

Cytoplasm.
Note: Seems to have a dominant-negative effect on localization of other isoforms, promoting their dissociation from the centrosome.

Ubiquitous. Highly expressed in heart and skeletal muscle. Isoform 1 is more expressed than isoform 5.

Homooligomer. Interacts with GSK3B/GSK3-beta via its C-terminal domain. Interacts with C14ORF166, such interaction may prevent its phosphorylation by GSK3B. Interacts with AUNIP (via N-terminus). Identified in a complex with AUNIP and AURKA. Interacts with CCDC120. Interacts (via C-terminus) with CEP250 (By similarity). Interacts with CEP170 (By similarity). Interacts with the gamma-tubulin ring complex component TUBGCP3 (By similarity). Interacts with gamma-tubulin (By similarity). Isoform 6 does not interact with CEP170 or CEP250 (By similarity).

There is conflicting information regarding the regions required for centrosomal localization. One study shows that the region 1601-1682 is necessary and sufficient for targeting to the centrosome (PubMed:12927815). Another study shows that a separate region, 1291-1575, is important for centrosomal localization (PubMed:15190203). However, a third study shows that the coiled-coil region (373-1885) is not sufficient for centrosomal localization and instead localizes to cytoplasmic speckles (By similarity). The observed differences might be due to oligomerization of the longer coiled-coil domain-containing sequence, which would mask the shorter centrosomal targeting sequences (By similarity).

The N-terminal domain is important for targeting to the mother centriole, although it is not sufficient by itself for centrosomal localization.