AI Article Synopsis
- The mitotic spindle apparatus is made up of microtubule networks anchored by kinetochores organized from centrosomes, with astral microtubules helping align the spindle during cell division.
- Researchers found that the protein RGS2, which relies on another protein called Nek7, is crucial for spindle formation and maintaining spindle structure during mitosis.
- Depletion of RGS2 leads to problems like delayed mitosis, incorrect chromosome alignment, and misorientation of the spindle, indicating that Nek7 and RGS2 work together to ensure proper spindle organization.
Article Abstract
The mitotic spindle apparatus is composed of microtubule (MT) networks attached to kinetochores organized from 2 centrosomes (a.k.a. spindle poles). In addition to this central spindle apparatus, astral MTs assemble at the mitotic spindle pole and attach to the cell cortex to ensure appropriate spindle orientation. We propose that cell cycle-related kinase, Nek7, and its novel interacting protein RGS2, are involved in mitosis regulation and spindle formation. We found that RGS2 localizes to the mitotic spindle in a Nek7-dependent manner, and along with Nek7 contributes to spindle morphology and mitotic spindle pole integrity. RGS2-depletion leads to a mitotic-delay and severe defects in the chromosomes alignment and congression. Importantly, RGS2 or Nek7 depletion or even overexpression of wild-type or kinase-dead Nek7, reduced γ-tubulin from the mitotic spindle poles. In addition to causing a mitotic delay, RGS2 depletion induced mitotic spindle misorientation coinciding with astral MT-reduction. We propose that these phenotypes directly contribute to a failure in mitotic spindle alignment to the substratum. In conclusion, we suggest a molecular mechanism whereupon Nek7 and RGS2 may act cooperatively to ensure proper mitotic spindle organization.
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| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4614950 | PMC |
| http://dx.doi.org/10.4161/15384101.2014.994988 | DOI Listing |
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