Zinc-Related Proteasome Variants in Type 1 Diabetes: An in Silico-Guided Case-Control Study.

Area of Science:

• Genetics and Molecular Biology
• Immunology
• Endocrinology

Background:

• The proteasome regulates protein degradation and immune responses, and is implicated in type 1 diabetes mellitus (T1DM) pathogenesis.
• Zinc (Zn2+) is crucial for insulin granule biogenesis and influences proteasomal activity.

Purpose of the Study:

• To investigate the association between single-nucleotide polymorphisms (SNPs) in proteasomal subunits that bind Zn2+ and T1DM susceptibility.
• To explore the relationship between these SNPs and T1DM-related traits, including microvascular complications and lipid profiles.

Main Methods:

• A case-control study involving 654 T1DM patients and 573 controls from Southern Brazil.
• In silico analysis identified five SNPs in proteasomal subunit genes (PSMA6, PSMB6, PSMB9, PSMC6, PSMD3) predicted to interact with Zn2+.
• Genotyping of selected SNPs was performed using TaqMan assays.

Main Results:

• The PSMC6 rs2295825C allele was associated with reduced risk of T1DM and diabetic retinopathy, and a more favorable lipid profile.
• The PSMB9 rs17587A/A genotype correlated with higher total cholesterol and HbA1c levels.
• The PSMA6 rs1048990G allele was linked to increased diabetic kidney disease prevalence, while PSMD3 rs3087852A was associated with lower urinary albumin excretion.

Conclusions:

• The PSMC6 rs2295825 SNP may provide a protective effect against T1DM.
• Specific SNPs in PSMC6, PSMB9, PSMA6, and PSMD3 genes appear to influence lipid metabolism and the development of diabetic microvascular complications.