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Nuclear transport of protein TTC4 depends on the cell cycle

Ruslan I Dmitriev1, Irina A Okkelman, Roman A Abdulin

  • 1Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya 16/10, 117997, Moscow, Russia. enisseisk@gmail.com

Cell and Tissue Research
|April 25, 2009
PubMed

Insights

Tetratricopeptide repeat domain protein 4 (TTC4) is ubiquitously expressed and dynamically translocates between the nucleus and cytoplasm during the cell cycle, potentially linking to its tumor suppressor function.

Area of Science:

  • Molecular Biology
  • Cell Biology
  • Cancer Research

Background:

  • Tetratricopeptide repeat domain protein 4 (TTC4) is implicated as a tumor suppressor in melanocyte transformation.
  • The relationships between TTC4 and DNA replication proteins, as well as its tissue distribution and subcellular localization, remain largely uncharacterized.

Purpose of the Study:

  • To investigate the tissue distribution and subcellular localization of TTC4.
  • To explore the factors influencing TTC4's subcellular localization, particularly its relationship with the cell cycle and protein interactions.

Main Methods:

  • Reverse transcription polymerase chain reaction (RT-PCR) was used to determine murine TTC4 gene expression.
  • Subcellular localization studies were performed using overexpression and co-expression systems.
  • Endogenous TTC4 localization was analyzed across different cell cycle phases.

Main Results:

  • The murine TTC4 gene exhibits ubiquitous expression across tissues.
  • Overexpressed TTC4 localizes to the cytoplasm, but co-expression with hampin/MSL1 induces nuclear translocation.
  • Endogenous TTC4 shows cell cycle-dependent localization: predominantly nuclear in G1/S phases and distributed between nucleus and cytoplasm in G2.

Conclusions:

  • TTC4 exhibits ubiquitous expression and its subcellular localization is dynamic and cell cycle-dependent.
  • Nuclear transport of TTC4 is a complex process influenced by protein interactions and cell cycle progression.
  • The cell cycle-dependent nuclear accumulation of TTC4 suggests a potential mechanism for its tumor suppressor activity.

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