The +1,506 (A>C) mutation in the 3' untranslated region affects β-globin expression

Area of Science:

• Molecular Biology
• Genetics
• Hematology

Background:

• The 3' untranslated region (3'UTR) of mRNA plays a crucial role in regulating gene expression, particularly mRNA stability.
• The precise mechanisms by which 3'UTR mutations affect beta-globin mRNA stability and contribute to beta-thalassemia remain incompletely understood.

Purpose of the Study:

• To investigate the impact of a specific mutation (+1,506 A>C) in the beta-globin 3'UTR on mRNA stability and protein expression.
• To determine if this mutation destabilizes beta-globin mRNA, leading to reduced protein levels and consequently causing beta-thalassemia.

Main Methods:

• Luciferase reporter assay was employed to assess gene expression efficiency.
• Recombinant pGL4.74 vectors were constructed, incorporating either wild-type or mutant beta-globin 3'UTR sequences.
• Comparative analysis included the studied mutation alongside six other known beta-thalassemia-associated mutations in the beta-globin 3'UTR.

Main Results:

• The +1,506 (A>C) mutation in the beta-globin 3'UTR resulted in a 30.0% decrease in protein expression compared to the wild-type sequence in the luciferase assay.
• This reduction in protein expression suggests a destabilization of the beta-globin mRNA molecule.

Conclusions:

• The +1,506 (A>C) mutation in the beta-globin 3'UTR is identified as a cause of beta-thalassemia due to its mRNA destabilizing effect.
• This mutation leads to decreased beta-globin protein levels, ultimately contributing to the pathogenesis of beta-thalassemia.
• The study underscores the significance of the beta-globin 3'UTR as a critical regulatory element for protein expression.