Long noncoding RNA HBBP1 enhances γ-globin expression through the ETS transcription factor ELK1

Area of Science:

• Genetics
• Molecular Biology
• Hematology

Background:

• Beta-thalassemia, a genetic blood disorder, results from defective adult hemoglobin (HbA) production.
• Reactivating fetal hemoglobin (HbF) is a therapeutic strategy for beta-thalassemia.
• Hemoglobin subunit beta pseudogene 1 (HBBP1) is linked to increased HbF, but its mechanism is unclear.

Purpose of the Study:

• To elucidate the mechanism by which HBBP1 influences gamma-globin expression.
• To investigate the role of HBBP1 and ELK1 in regulating HbF production.

Main Methods:

• Bioinformatics analysis to identify HBBP1's role in gamma-globin production.
• Gene overexpression studies in K562 and HUDEP-2 cells.
• Analysis of HBBP1 and ELK1 interactions and promoter activities.

Main Results:

• HBBP1 overexpression increased gamma-globin at transcript and protein levels.
• ELK1 transcription factor binds to and activates the HBBP1 promoter.
• ELK1 overexpression enhanced gamma-globin synthesis and directly activated its promoter.
• HBBP1 and ELK1 were found to interact in cells.

Conclusions:

• HBBP1 induces gamma-globin expression, at least partly, by enhancing ELK1 expression.
• This pathway provides potential targets for reactivating gamma-globin in beta-thalassemia treatment.