NCBI Summary:
This gene encodes a 50-kD subunit of dynactin, a macromolecular complex consisting of 10-11 subunits ranging in size from 22 to 150 kD. Dynactin binds to both microtubules and cytoplasmic dynein. It is involved in a diverse array of cellular functions, including ER-to-Golgi transport, the centripetal movement of lysosomes and endosomes, spindle formation, chromosome movement, nuclear positioning, and axonogenesis. This subunit is present in 4-5 copies per dynactin molecule. It contains three short alpha-helical coiled-coil domains that may mediate association with self or other dynactin subunits. It may interact directly with the largest subunit (p150) of dynactin and may affix p150 in place.
General function
Cytoskeleton
Comment
Cellular localization
Cytoplasmic
Comment
Ovarian function
Comment
Expression regulated by
Comment
Ovarian localization
Oocyte
Comment
PAR-1 and the microtubule-associated proteins CLASP2 and dynactin-p50 have specific localisation on mouse meiotic and first mitotic spindles Moore CA, et al .
The site of second meiotic division, marked by the second polar body, is an important reference point in the early mouse embryo. To study its formation, we look at the highly asymmetric meiotic divisions. For extrusion of the small polar bodies during meiosis, the spindles must be located cortically. The positioning of meiotic spindles is known to involve the actin cytoskeleton, but whether microtubules are also involved is not clear. In this study we investigated the patterns of localisation of microtubule regulatory proteins in mouse oocytes. PAR-1 is a member of the PAR (partitioning-defective) family with known roles in regulation of microtubule stability and spindle positioning in other model systems. Here we show its specific localisation on mouse meiotic and first mitotic spindles. In addition, the microtubule-associated proteins CLASP2 (a CLIP associating protein) and dynactin-p50 are found on kinetochores and a subset of microtubule-organising centres. Thus we show specific localisation of microtubule regulatory proteins in mouse oocytes, which could indicate roles in meiotic spindle organisation.