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Targeting Cysteine Thiols for in Vitro Site-specific Glycosylation of Recombinant Proteins
Published on: October 4, 2017
Modulation of CTNS gene expression by intracellular thiols
Francesco Bellomo1, Serena Corallini, Anna Pastore
1Department of Nephrology and Urology, Bambino Gesù Children's Hospital and Research Institute, Rome, Italy.
Free Radical Biology & Medicine
|January 19, 2010
Summary
Nephropathic cystinosis involves cell damage linked to the cysteine/cystine (Cys/CySS) system. CTNS gene expression is influenced by cellular redox state, impacting Cys/CySS levels and disease mechanisms.
Area of Science:
- Biochemistry
- Cell Biology
- Genetics
Background:
- The cysteine/cystine (Cys/CySS) couple is a key cellular thiol/disulfide system regulating metabolic pathways and redox state.
- Nephropathic cystinosis (NC) results from CTNS gene mutations, leading to cystinosin deficiency and lysosomal cystine accumulation, causing renal cellular dysfunction.
Purpose of the Study:
- To investigate the interplay between CTNS gene expression and cellular thiol/disulfide systems (Cys/CySS and GSH/GSSG).
- To elucidate the mechanisms underlying cell damage in nephropathic cystinosis by examining the effects of CTNS gene manipulation and altered redox states.
Main Methods:
- Investigated the impact of CTNS gene overexpression and silencing on intracellular Cys/CySS and GSH/GSSG redox states.
- Analyzed changes in Cys/CySS and GSH/GSSG redox couples under conditions of extracellular Cys/CySS deprivation and altered intracellular redox environments.
- Measured CTNS mRNA levels in response to varying extracellular and intracellular redox conditions.
Main Results:
- CTNS gene overexpression did not significantly alter intracellular Cys/CySS or GSH/GSSG redox states.
- CTNS gene silencing led to increased intracellular CySS and Cys, decreased GSH and GSSG, and a mild increase in the Cys/CySS redox state.
- Extracellular Cys/CySS deprivation oxidized Cys/CySS and GSH/GSSG redox couples and upregulated CTNS mRNA levels.
- A reduced intracellular environment (lower GSH/GSSG and Cys/CySS redox potentials) downregulated CTNS mRNA levels.
- CTNS gene expression was found to be correlated with intracellular Cys levels and the Cys/CySS redox state.
Conclusions:
- Cellular redox state, particularly the Cys/CySS couple, influences CTNS gene expression.
- Altered redox homeostasis may contribute to the pathogenesis of nephropathic cystinosis.
- Understanding the relationship between CTNS and cellular redox systems provides insights into NC mechanisms and potential therapeutic targets.
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