Cerebroventricular Microinjections of MPTP on Adult Zebrafish Induces Dopaminergic Neuronal Death, Mitochondrial Fragmentation, and Sensorimotor Impairments

Mitochondria are dynamic organelles that mediate the energetic supply to cells and mitigate oxidative stress through the intricate balance of fission and fusion. Mitochondrial dysfunction is a prominent feature within Parkinson disease (PD) etiologies. To date, there have been conflicting studies of neurotoxin impact on dopaminergic cell death, mitochondrial function and behavioral impairment using adult zebrafish. Here, we performed cerebroventricular microinjections (CVMIs) of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) on adult transgenic zebrafish that resulted in significant reductions in dopaminergic neurons within the telencephalon and olfactory bulbs (OB) of Tg(dat:eGFP) fish. Visualization of mCherry and mitochondrial gene expression analysis in Tg(dat:tom20 MLS:mCherry) fish reveal that MPTP induces mitochondrial fragmentation in dopaminergic neurons and the activation of the pink1/parkin pathway involved mitophagy. Moreover, the loss of dopaminergic neurons translated into a transient locomotor and olfactory phenotype. Taken together, these data can contribute to a better understanding of the mitochondrial impact on dopaminergic survivability.

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Faculty Opinions recommendation of Adult-onset obesity is triggered by impaired mitochondrial gene expression.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.728768996.793536505 ◽

2017 ◽

Author(s):

Michael Miller ◽

Ekta Tiwary

Keyword(s):

Gene Expression ◽

Mitochondrial Gene ◽

Mitochondrial Gene Expression ◽

Adult Onset

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Neuroprotection by Progesterone through Stimulation of Mitochondrial Gene Expression

10.21236/ada392823 ◽

2000 ◽

Author(s):

Gary Fiskum

Keyword(s):

Gene Expression ◽

Mitochondrial Gene ◽

Mitochondrial Gene Expression ◽

Stimulation Of

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Mitochondrial Glucocorticoid Receptors and Their Actions

International Journal of Molecular Sciences ◽

10.3390/ijms22116054 ◽

2021 ◽

Vol 22 (11) ◽

pp. 6054

Author(s):

Ioanna Kokkinopoulou ◽

Paraskevi Moutsatsou

Keyword(s):

Gene Expression ◽

Glucocorticoid Receptors ◽

Mitochondrial Gene ◽

Cell Types ◽

Ros Generation ◽

Mitochondrial Gene Expression ◽

Mitochondrial Energy Metabolism ◽

Bcl2 Family ◽

Cellular Processes ◽

Almost All

Mitochondria are membrane organelles present in almost all eukaryotic cells. In addition to their well-known role in energy production, mitochondria regulate central cellular processes, including calcium homeostasis, Reactive Oxygen Species (ROS) generation, cell death, thermogenesis, and biosynthesis of lipids, nucleic acids, and steroid hormones. Glucocorticoids (GCs) regulate the mitochondrially encoded oxidative phosphorylation gene expression and mitochondrial energy metabolism. The identification of Glucocorticoid Response Elements (GREs) in mitochondrial sequences and the detection of Glucocorticoid Receptor (GR) in mitochondria of different cell types gave support to hypothesis that mitochondrial GR directly regulates mitochondrial gene expression. Numerous studies have revealed changes in mitochondrial gene expression alongside with GR import/export in mitochondria, confirming the direct effects of GCs on mitochondrial genome. Further evidence has made clear that mitochondrial GR is involved in mitochondrial function and apoptosis-mediated processes, through interacting or altering the distribution of Bcl2 family members. Even though its exact translocation mechanisms remain unknown, data have shown that GR chaperones (Hsp70/90, Bag-1, FKBP51), the anti-apoptotic protein Bcl-2, the HDAC6- mediated deacetylation and the outer mitochondrial translocation complexes (Tom complexes) co-ordinate GR mitochondrial trafficking. A role of mitochondrial GR in stress and depression as well as in lung and hepatic inflammation has also been demonstrated.

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Mitochondrial Mistranslation in Brain Provokes a Metabolic Response Which Mitigates the Age-Associated Decline in Mitochondrial Gene Expression

International Journal of Molecular Sciences ◽

10.3390/ijms22052746 ◽

2021 ◽

Vol 22 (5) ◽

pp. 2746

Author(s):

Dimitri Shcherbakov ◽

Reda Juskeviciene ◽

Adrián Cortés Sanchón ◽

Margarita Brilkova ◽

Hubert Rehrauer ◽

...

Keyword(s):

Gene Expression ◽

Metabolic Response ◽

Mitochondrial Gene ◽

Tca Cycle ◽

Brain Mitochondria ◽

Mitochondrial Gene Expression ◽

Rna Seq ◽

The Tca Cycle ◽

Neurological Phenotype

Mitochondrial misreading, conferred by mutation V338Y in mitoribosomal protein Mrps5, in-vivo is associated with a subtle neurological phenotype. Brain mitochondria of homozygous knock-in mutant Mrps5V338Y/V338Y mice show decreased oxygen consumption and reduced ATP levels. Using a combination of unbiased RNA-Seq with untargeted metabolomics, we here demonstrate a concerted response, which alleviates the impaired functionality of OXPHOS complexes in Mrps5 mutant mice. This concerted response mitigates the age-associated decline in mitochondrial gene expression and compensates for impaired respiration by transcriptional upregulation of OXPHOS components together with anaplerotic replenishment of the TCA cycle (pyruvate, 2-ketoglutarate).

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Regulation of nuclear and mitochondrial gene expression by contractile activity in skeletal muscle.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(17)42482-3 ◽

1986 ◽

Vol 261 (1) ◽

pp. 376-380 ◽

Cited By ~ 15

Author(s):

R S Williams ◽

S Salmons ◽

E A Newsholme ◽

R E Kaufman ◽

J Mellor

Keyword(s):

Gene Expression ◽

Skeletal Muscle ◽

Contractile Activity ◽

Mitochondrial Gene ◽

Mitochondrial Gene Expression

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Contribution of PGC-1α to Obesity- and Caloric Restriction-Related Physiological Changes in White Adipose Tissue

International Journal of Molecular Sciences ◽

10.3390/ijms22116025 ◽

2021 ◽

Vol 22 (11) ◽

pp. 6025

Author(s):

Masaki Kobayashi ◽

Yusuke Deguchi ◽

Yuka Nozaki ◽

Yoshikazu Higami

Keyword(s):

Adipose Tissue ◽

Caloric Restriction ◽

White Adipose Tissue ◽

Mitochondrial Gene ◽

Energy Resource ◽

Peroxisome Proliferator ◽

Physiological Changes ◽

Mitochondrial Gene Expression ◽

Peroxisome Proliferator Activated Receptor ◽

White Adipocytes

Peroxisome proliferator-activated receptor γ coactivator-1 α (PGC-1α) regulates mitochondrial DNA replication and mitochondrial gene expression by interacting with several transcription factors. White adipose tissue (WAT) mainly comprises adipocytes that store triglycerides as an energy resource and secrete adipokines. The characteristics of WAT vary in response to systemic and chronic metabolic alterations, including obesity or caloric restriction. Despite a small amount of mitochondria in white adipocytes, accumulated evidence suggests that mitochondria are strongly related to adipocyte-specific functions, such as adipogenesis and lipogenesis, as well as oxidative metabolism for energy supply. Therefore, PGC-1α is expected to play an important role in WAT. In this review, we provide an overview of the involvement of mitochondria and PGC-1α with obesity- and caloric restriction-related physiological changes in adipocytes and WAT.

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Quantitative proteomics revealed C6orf203/MTRES1 as a factor preventing stress-induced transcription deficiency in human mitochondria

Nucleic Acids Research ◽

10.1093/nar/gkz542 ◽

2019 ◽

Vol 47 (14) ◽

pp. 7502-7517 ◽

Cited By ~ 6

Author(s):

Anna V Kotrys ◽

Dominik Cysewski ◽

Sylwia D Czarnomska ◽

Zbigniew Pietras ◽

Lukasz S Borowski ◽

...

Keyword(s):

Gene Expression ◽

Rna Binding ◽

Mitochondrial Gene ◽

Binding Activity ◽

Stress Conditions ◽

Mitochondrial Rna ◽

Mitochondrial Gene Expression ◽

Compensatory Mechanisms ◽

Temporary Reduction ◽

Mitochondrial Transcription

AbstractMaintenance of mitochondrial gene expression is crucial for cellular homeostasis. Stress conditions may lead to a temporary reduction of mitochondrial genome copy number, raising the risk of insufficient expression of mitochondrial encoded genes. Little is known how compensatory mechanisms operate to maintain proper mitochondrial transcripts levels upon disturbed transcription and which proteins are involved in them. Here we performed a quantitative proteomic screen to search for proteins that sustain expression of mtDNA under stress conditions. Analysis of stress-induced changes of the human mitochondrial proteome led to the identification of several proteins with poorly defined functions among which we focused on C6orf203, which we named MTRES1 (Mitochondrial Transcription Rescue Factor 1). We found that the level of MTRES1 is elevated in cells under stress and we show that this upregulation of MTRES1 prevents mitochondrial transcript loss under perturbed mitochondrial gene expression. This protective effect depends on the RNA binding activity of MTRES1. Functional analysis revealed that MTRES1 associates with mitochondrial RNA polymerase POLRMT and acts by increasing mitochondrial transcription, without changing the stability of mitochondrial RNAs. We propose that MTRES1 is an example of a protein that protects the cell from mitochondrial RNA loss during stress.

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