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Isolation and Functional Analysis of Mitochondria from Cultured Cells and Mouse Tissue
09:27

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Published on: March 23, 2015

Changes of mitochondria and relocation of the apoptosis-inducing factor during apoptosis

A Ivana Scovassi1, Cristiana Soldani, Paola Veneroni

  • 1Istituto di Genetica Molecolare, Consiglio Nazionale delle Ricerche, Pavia, Italy. scovassi@igm.cnr.it

Annals of the New York Academy of Sciences
|September 3, 2009
PubMed

Insights

Apoptosis-inducing factor (AIF) translocates to the nucleus during early apoptosis. In late apoptosis, AIF remains primarily in mitochondria, separate from fragmented chromatin.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • Apoptosis-inducing factor (AIF) is a key protein involved in programmed cell death.
  • AIF is known to translocate from mitochondria to the nucleus during apoptosis.

Purpose of the Study:

  • To investigate the spatiotemporal dynamics of AIF during apoptosis in HeLa cells.
  • To analyze the relationship between AIF localization and chromatin changes in different stages of apoptosis.

Main Methods:

  • HeLa cells were induced into apoptosis using etoposide or actinomycin D.
  • Immunolabeling techniques were used to track the localization of AIF and cytochrome c.
  • Mitochondrial structure and function were assessed.

Main Results:

  • Mitochondrial alterations and translocation of cytochrome c and AIF to the nucleus were observed in early apoptosis.
  • In late apoptosis, with fragmented chromatin, AIF immunolabeling was distinct from chromatin and localized mainly to mitochondria.

Conclusions:

  • AIF exhibits dynamic localization changes during apoptosis, moving to the nucleus in early stages.
  • AIF's localization shifts back to mitochondria in late apoptosis, independent of chromatin fragmentation.

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