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RecQ helicase expression in patients with telomeropathies
João Paulo L Silva1, Flávia S Donaires1, Fernanda Gutierrez-Rodrigues2
1Department of Medical Imaging, Hematology, and Oncology, Ribeirão Preto Medical School, University of São Paulo, Av. Bandeirantes, 3900 - 7 o andar, sala 743 - HCRP, Ribeirão Preto, SP, 14049-900, Brazil.
Molecular Biology Reports
|June 14, 2024
Summary
Telomeropathy patients show reduced expression of RecQ helicases, crucial for DNA repair and telomere maintenance. This downregulation affects multiple DNA repair genes, offering insights into disease mechanisms.
Area of Science:
- Genetics
- Molecular Biology
- Cell Biology
Background:
- Telomeropathies are inherited disorders linked to telomere maintenance gene variants.
- RecQ and RTEL1 helicases are vital for unwinding telomeric structures and preventing replication defects.
- Germline variants in RTEL1 are a known cause of telomeropathies.
Purpose of the Study:
- To investigate the expression of RecQ and RTEL1 helicase genes in telomeropathy patients.
- To determine if RecQ helicase expression is altered in peripheral blood mononuclear cells (PBMCs) of patients.
Main Methods:
- Examined mRNA expression levels of RecQ helicases (RECQL1, BLM, WRN, RECQL4, RECQL5) and RTEL1.
- Analyzed gene expression in PBMCs from human telomeropathy patients.
- Assessed expression of DNA damage repair genes and RecQ functional partners.
Main Results:
- Significant downregulation of all RecQ helicase mRNA expression levels observed in patients' primary cells.
- RTEL1 mRNA expression was not significantly altered.
- Fifteen additional genes involved in DNA damage repair and RecQ partnership were also downregulated.
Conclusions:
- RecQ helicase gene expression is downregulated in PBMCs of telomeropathy patients.
- The findings suggest a broader impact on DNA repair pathways in these patients.
- This downregulation is not due to general cellular exhaustion.
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