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Cell cycle specific expression and nucleolar localization of human J-domain containing co-chaperone Mrj

Sanjib Dey1, Paromita Banerjee, Partha Saha

  • 1Crystallography and Molecular Biology Division, Saha Institute of Nuclear Physics, Sector I, Block AF, Bidhannagar, Kolkata, 700064, India.

Molecular and Cellular Biochemistry
|November 13, 2008
PubMed

Insights

Mammalian relative to DnaJ (Mrj) protein is upregulated during cell division (M-phase) in HeLa cells. Its localization changes throughout the cell cycle, suggesting a role in mitosis.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • J-domain containing co-chaperone Mrj (mammalian relative to DnaJ) is involved in placental development and inhibiting Huntingtin-mediated cytotoxicity.
  • Mrj interacts with keratin intermediate filaments, which are known to reorganize extensively during cell division.

Purpose of the Study:

  • To investigate the potential role of Mrj in cell cycle regulation, specifically during mitosis.
  • To determine the cell cycle-specific expression and subcellular localization of Mrj.

Main Methods:

  • Analysis of Mrj protein expression levels in different phases of the cell cycle using HeLa cells.
  • Microscopic examination of Mrj subcellular localization during interphase and mitosis.

Main Results:

  • Mrj protein expression is significantly upregulated during the M-phase (mitosis) of HeLa cells.
  • Mrj exhibits dynamic subcellular localization, being dispersed throughout the cell in late mitosis and localized to the nucleolus during interphase.

Conclusions:

  • The cell cycle-specific expression and differential subcellular localization of Mrj suggest its involvement in mitosis-related activities.
  • Mrj's activity appears to be regulated by its cell cycle-dependent expression and localization patterns.

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