RNA-binding protein PCBP2 regulates pancreatic β cell function and adaptation to glucose

Area of Science:

• Endocrinology
• Molecular Biology
• Diabetes Research

Background:

• Glucose is vital for pancreatic beta cell function, but mechanisms linking nutrient sensing to cellular adaptation in type 2 diabetes (T2D) are unclear.
• Beta cells alter mRNA metabolism in response to hyperglycemia, a key feature of T2D.

Purpose of the Study:

• To investigate the role of the RNA-binding protein PCBP2 in maintaining beta cell function under basal and hyperglycemic conditions.
• To elucidate the mechanisms by which PCBP2 influences insulin secretion and beta cell adaptation.

Main Methods:

• Studied PCBP2 expression in mouse islets exposed to elevated glucose.
• Performed transcriptomic analysis on Pcbp2-deficient beta cells.
• Assessed insulin secretion, calcium flux, and insulin granule exocytosis.

Main Results:

• PCBP2 expression increased with glucose and was essential for adapting insulin secretion.
• PCBP2 deficiency impaired genes in the insulin secretory pathway, leading to defects in calcium flux, insulin granule function, and secretion amplification.
• PCBP2 was downregulated in human islets from T2D donors and affected genes linked to T2D.

Conclusions:

• PCBP2 is essential for basal and glucose-adaptive gene programs in beta cells.
• PCBP2 plays a critical role in maintaining beta cell function and insulin secretion, suggesting its potential as a therapeutic target for T2D.