Related Experiment Video
Updated: Jul 6, 2025
07:26
Discrimintion and Mapping of the Primary and Processed Transcripts in Maize Mitochondrion Using a Circular RT-PCR-based Strategy
Published on: July 29, 2019
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Uncovering the Localization and Function of a Novel Read-Through Transcript 'TOMM40-APOE'
Shichen Chang1,2, Satoru Torii1, Jun Inamo3
1Department of Pathological Cell Biology, Medical Research Institute, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan.
Cells
|January 11, 2024
Summary
A novel read-through transcript, TOMM40-APOE, was identified. This mitochondrial protein, TOMM40-APOE, induces cell death, unlike its secreted counterparts, APOE3 and APOE4.
Area of Science:
- Genomics
- Molecular Biology
- Cell Biology
Background:
- Genome analysis reveals read-through transcripts skipping polyA signals.
- Understanding novel transcript variants is crucial for cellular function.
Purpose of the Study:
- Identify and characterize a new read-through transcript, TOMM40-APOE.
- Investigate the cellular localization and function of TOMM40-APOE isoforms.
Main Methods:
- cDNA amplification from THP-1 cells.
- Generation of TOMM40-APOE3 and TOMM40-APOE4 isoforms.
- Mitochondrial localization and cell death assays.
Main Results:
- TOMM40-APOE3 and TOMM40-APOE4 were successfully generated.
- Unlike secreted APOE3/APOE4, TOMM40-APOE isoforms localized to mitochondria.
- TOMM40-APOE isoforms increased cell death without affecting mitochondrial membrane potential.
Conclusions:
- The novel mitochondrial protein TOMM40-APOE exhibits cell-toxic properties.
- TOMM40-APOE isoforms represent a distinct functional class compared to secreted APOE.
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