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Updated: Jul 9, 2026
15:12
Purification of the Cystic Fibrosis Transmembrane Conductance Regulator Protein Expressed in Saccharomyces cerevisiae
Published on: May 10, 2014
CISD1 codifies a mitochondrial protein upregulated by the CFTR channel
Guillermo L Taminelli1, Verónica Sotomayor, Angel G Valdivieso
1Laboratorio de Biología Celular y Molecular, Instituto de Investigaciones Bioquímicas de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Argentina.
Biochemical and Biophysical Research Communications
|December 1, 2007
Summary
Cystic fibrosis (CF) is linked to altered gene expression. Researchers identified CISD1 as a new gene regulated by the CFTR channel, showing its expression changes with CFTR activity and potential mitochondrial involvement.
Area of Science:
- Molecular Biology
- Genetics
- Cell Biology
Background:
- Cystic fibrosis (CF) is an autosomal recessive disorder resulting from mutations in the CFTR chloride channel.
- CFTR dysfunction impacts the expression of numerous genes.
- Mitochondrial dysfunction is increasingly recognized as a factor in CF pathogenesis.
Purpose of the Study:
- To identify and characterize novel genes regulated by the CFTR chloride channel.
- To investigate the role of CISD1 in cystic fibrosis.
- To explore the potential link between CFTR, CISD1, and mitochondrial function.
Main Methods:
- Gene expression analysis (mRNA levels) in CF cells and cells with restored CFTR function.
- Pharmacological inhibition and stimulation of CFTR chloride transport activity.
- Subcellular localization studies using a CISD1-GFP chimera and PSORT II prediction.
Main Results:
- CISD1 mRNA expression is significantly down-regulated in cystic fibrosis cells.
- Ectopic expression of wild-type CFTR restores CISD1 mRNA levels in CF cells.
- Inhibition of CFTR activity reduces CISD1 mRNA, while stimulation upregulates it.
- CISD1 is localized to mitochondria, suggesting a role in mitochondrial regulation.
Conclusions:
- CISD1 is a novel CFTR-dependent gene.
- CFTR activity directly influences CISD1 expression.
- The findings suggest a potential role for CISD1 in CFTR-mediated mitochondrial dysfunction in cystic fibrosis.
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