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Steroidogenic factor 1 (NR5A1) maintains centrosome homeostasis in steroidogenic cells by restricting centrosomal

Chia-Yih Wang1, Yung-Hsin Kao, Pao-Yen Lai

  • 1Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan.

Molecular and Cellular Biology
|November 21, 2012
PubMed

Insights

Steroidogenic factor 1 (SF-1) prevents centrosome overduplication by inhibiting DNA-dependent protein kinase (DNA-PK) signaling within the centrosome, ensuring cell survival and proper cell division.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Nuclear Receptors

Background:

  • Steroidogenic factor 1 (SF-1) is crucial for adrenogenital cell development.
  • SF-1's role in cell survival, particularly its mechanism in preventing apoptosis, requires further elucidation.
  • SF-1 also plays a role in centrosome homeostasis beyond its nuclear functions.

Purpose of the Study:

  • To investigate the mechanism by which SF-1 regulates cell survival.
  • To determine SF-1's role in centrosome homeostasis and its impact on cell division.
  • To elucidate SF-1's interaction with DNA-dependent protein kinase (DNA-PK) signaling in the centrosome.

Main Methods:

  • Investigated SF-1 localization and function in centrosomes using knockout mouse models.
  • Analyzed the interaction of SF-1 with Ku70/80 and DNA-PKcs in the centrosome.
  • Assessed the impact of SF-1 depletion on centrosomal Akt, CDK2/cyclin A activation, and centrosome overduplication.
  • Examined nuclear DNA damage response and centriole biogenesis upon SF-1 depletion.

Main Results:

  • SF-1 sequesters Ku70/80 in the centrosome, preventing DNA-PKcs recruitment and activation.
  • SF-1 depletion leads to aberrant centrosomal DNA-PK activation, activating Akt and CDK2/cyclin A, resulting in centrosome overduplication.
  • Centrosome overduplication due to SF-1 loss is rescued by inhibiting DNA-PK, Ku70/80, cyclin A, CDK2, or Akt.
  • SF-1 depletion does not affect nuclear DNA damage response or centriole biogenesis.

Conclusions:

  • SF-1 controls centrosome homeostasis by inhibiting aberrant centrosomal DNA-PK signaling.
  • SF-1's centrosomal function is critical for preventing centrosome overduplication and ensuring cell survival.
  • This study reveals a novel role for SF-1 in regulating cell division through centrosomal pathways distinct from nuclear DNA damage responses.

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