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UXT (Ubiquitously Expressed Transcript) causes mitochondrial aggregation

Tijuana N Moss1, Amy Vo, Wallace L McKeehan

  • 1Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, Texas A&M Health Science Center, Texas Medical Center, Houston, TX 77030, USA.

In Vitro Cellular & Developmental Biology. Animal
|June 8, 2007
PubMed

Insights

Ubiquitously expressed transcript (UXT) causes mitochondria to aggregate and invade the nucleus, leading to cell death. This study reveals UXT

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • Mitochondria are crucial for cellular energy and apoptosis.
  • Mitochondrial distribution is regulated by the cytoskeleton.
  • Perinuclear mitochondrial aggregation is linked to cell death.

Purpose of the Study:

  • To investigate the role of ubiquitously expressed transcript (UXT) in mitochondrial distribution and cell death.
  • To understand the mechanism by which UXT influences mitochondrial aggregation.

Main Methods:

  • Overexpression of green fluorescent protein-tagged UXT (GFP-UXT) in mammalian cells.
  • Observation of GFP-UXT localization and distribution patterns over time.
  • Correlation of GFP-UXT aggregation with mitochondrial and LRPPRC aggregation.

Main Results:

  • GFP-UXT exhibited four distinct distribution patterns correlating with protein levels and time.
  • UXT overexpression led to progressive mitochondrial aggregation, starting in the cytosol and culminating in nuclear invasion.
  • GFP-UXT aggregates were found to coincide with aggregates of mitochondria and LRPPRC.

Conclusions:

  • Increasing UXT concentrations promote progressive mitochondrial aggregation.
  • UXT may contribute to cell death by associating with LRPPRC, affecting mitochondrial distribution and nuclear integrity.

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