Related Experiment Video

Updated: Jun 25, 2026

An In Vitro Approach to Study Mitochondrial Dysfunction: A Cybrid Model
06:05

An In Vitro Approach to Study Mitochondrial Dysfunction: A Cybrid Model

Published on: March 9, 2022

Disorders from perturbations of nuclear-mitochondrial intergenomic cross-talk

A Spinazzola1, M Zeviani

  • 1Unit of Molecular Neurogenetics, C. Besta Neurological Institute, Foundation IRCCS, Milano, Italy.

Journal of Internal Medicine
|February 5, 2009
PubMed

Insights

Mitochondrial DNA (mtDNA) relies on nuclear DNA for its function. Mutations disrupting this nuclear-mitochondrial communication cause genetic disorders affecting mtDNA levels and protein production.

Area of Science:

  • Molecular Biology
  • Genetics
  • Cell Biology

Background:

  • Mitochondria, once independent, are now integrated with the nuclear genome.
  • Mitochondrial DNA (mtDNA) relies on numerous nucleus-encoded factors for maintenance and expression.
  • The intricate relationship between nuclear and mitochondrial genomes is crucial for cellular function.

Purpose of the Study:

  • To investigate the consequences of disrupted nuclear-mitochondrial cross-talk.
  • To understand the mechanisms leading to mtDNA maintenance disorders.
  • To explore the genetic basis of Mendelian disorders affecting mitochondrial function.

Main Methods:

  • Analysis of nucleus-encoded factors essential for mtDNA integrity.
  • Investigating mutations affecting mtDNA replication and expression.
  • Studying the impact of genetic alterations on mtDNA quantity and quality.

Main Results:

  • Mutations in nucleus-encoded factors disrupt the nuclear-mitochondrial cross-talk.
  • These disruptions lead to qualitative (multiple deletions) or quantitative (depletion) alterations in mtDNA.
  • Defective translation of mtDNA-encoded respiratory chain components is observed.

Conclusions:

  • The integrity of mitochondrial DNA is critically dependent on nuclear-encoded factors.
  • Disruptions in this genetic communication cause Mendelian disorders with distinct mtDNA phenotypes.
  • Understanding these interactions is key to diagnosing and potentially treating mitochondrial diseases.

More Related Videos

Transmitochondrial Cybrid Generation Using Cancer Cell Lines07:49

Transmitochondrial Cybrid Generation Using Cancer Cell Lines

Published on: March 17, 2023

Isolation of Mitochondria for Mitochondrial Supercomplex Analysis from Small Tissue and Cell Culture Samples05:45

Isolation of Mitochondria for Mitochondrial Supercomplex Analysis from Small Tissue and Cell Culture Samples

Published on: May 3, 2024

Related Concept Videos

Animal Mitochondrial Genetics02:59

Animal Mitochondrial Genetics

Among all the organelles in an animal cell, only mitochondria have their own independent genomes. Animal mitochondrial DNA is a double-stranded, closed-circular molecule with around 20,000 base pairs. Mitochondrial DNA is unique in that one of its two strands, the heavy, or H, -strand is guanine rich, whereas the complementary strand is cytosine rich and called the light, or L, -strand. Compared to nuclear DNA, mitochondrial DNA has a very low percentage of non-coding regions and is marked by...
Mitochondrial Membranes01:45

Mitochondrial Membranes

A single mitochondrion is a bean-shaped organelle enclosed by a double-membrane system. The outer membrane of mitochondria is smooth and contains many porins - the integral membrane transporters. Porins enable free diffusion of ions and small uncharged molecules through the outer mitochondrial membrane but limit the transport of molecules larger than 5000 Daltons. Further, the outer mitochondrial membrane forms a unique structure called membrane contact sites with other subcellular organelles,...
Electron Transport Chain: Complex I and II01:46

Electron Transport Chain: Complex I and II

The mitochondrial electron transport chain (ETC) is the main energy generation system in the eukaryotic cells. However, mitochondria also produce cytotoxic reactive oxygen species (ROS) due to the large electron flow during oxidative phosphorylation. While Complex I is one of the primary sources of superoxide radicals, ROS production by Complex II is uncommon and may only be observed in cancer cells with mutated complexes.
ROS generation is regulated and maintained at moderate levels necessary...
Export of Mitochondrial and Chloroplast Genes02:19

Export of Mitochondrial and Chloroplast Genes

A eukaryotic cell can have up to three different types of genetic systems: nuclear, mitochondrial, and chloroplast. During evolution, organelles have exported many genes to the nucleus; this transfer is still ongoing in some plant species. Approximately 18% of the Arabidopsis thaliana nuclear genome is thought to be derived from the chloroplast’s cyanobacterial ancestor, and around 75% of the yeast genome derived from the mitochondria’s bacterial ancestor. This export has occurred irrespective...
Mismatch Repair01:20

Mismatch Repair

Organisms are capable of detecting and fixing nucleotide mismatches that occur during DNA replication. This sophisticated process requires identifying the new strand and replacing the erroneous bases with correct nucleotides. Mismatch repair is coordinated by many proteins in both prokaryotes and eukaryotes.
The Mutator Protein Family Plays a Key Role in DNA Mismatch Repair
The human genome has more than 3 billion base pairs of DNA per cell. Prior to cell division, that vast amount of genetic...
Mitochondria01:37

Mitochondria

Mitochondria are eukaryotic cellular organelles that are known to produce energy through a process called oxidative phosphorylation. Besides their primary function, mitochondria are involved in various cellular processes, including cell growth, differentiation, signaling, metabolism, and senescence. Age-related changes cause a decline in mitochondrial quality and integrity due to increased mitochondrial mutations and oxidative damage. Thus, aging can severely impact mitochondrial functions,...