Circular RNA circNUP214 serves as a microRNA-31 sponge to promote the progression of myasthenia gravis through NFAT5

Area of Science:

• Immunology
• Molecular Biology
• Genetics

Background:

• Myasthenia gravis (MG) is an autoimmune neuromuscular junction disorder.
• Circular RNAs (circRNAs) are implicated in MG, but their specific roles are unclear.
• The function of circNUP214 in MG pathogenesis has not been previously investigated.

Purpose of the Study:

• To investigate the expression and function of circNUP214 in patients with acetylcholine receptor (AChR) antibody-positive myasthenia gravis.
• To elucidate the regulatory mechanism of circNUP214 involving miR-31 and NFAT5 in CD4+ T cells.

Main Methods:

• Quantitative real-time PCR (qRT-PCR) to measure circNUP214 expression in peripheral blood mononuclear cells (PBMCs) and CD4+ T cells.
• Verification of circNUP214's structure and localization.
• Confirmation of circNUP214 interaction with miR-31 and assessment of its effect on CD4+ T cell proliferation.
• Rescue experiments in Jurkat cells to validate the circNUP214/miR-31/NFAT5 ceRNA axis.

Main Results:

• circNUP214 expression was significantly higher in PBMCs and CD4+ T cells of MG patients compared to healthy controls.
• circNUP214 promoted CD4+ T cell proliferation, while its knockdown inhibited this effect.
• circNUP214 directly binds to miR-31, upregulating NFAT5 expression by sponging miR-31, forming a ceRNA regulatory axis.

Conclusions:

• circNUP214 is upregulated in AChR-positive MG patients and contributes to aberrant CD4+ T cell proliferation.
• The circNUP214/miR-31/NFAT5 axis represents a novel regulatory pathway in MG pathogenesis.
• circNUP214 may serve as a potential diagnostic biomarker or therapeutic target for myasthenia gravis.