NEAT1 scaffolds RNA-binding proteins and the Microprocessor to globally enhance pri-miRNA processing

Area of Science:

• Molecular Biology
• Genetics
• RNA Biology

Background:

• MicroRNA (miRNA) biogenesis is crucial for gene regulation.
• RNA-binding proteins (RBPs) modulate miRNA processing, but typically affect limited targets.
• The NONO-PSF heterodimer and the long noncoding RNA NEAT1 are involved in nuclear organization.

Purpose of the Study:

• To investigate the global role of the NONO-PSF heterodimer in pri-miRNA processing.
• To determine the impact of the long noncoding RNA NEAT1 on miRNA biogenesis.
• To elucidate the mechanism by which NEAT1 influences pri-miRNA processing.

Main Methods:

• RNA-binding protein immunoprecipitation (RIP) in HeLa cells.
• Analysis of pri-miRNA expression and processing.
• RNA pull-down assays and interaction studies.
• Investigation of NEAT1 structure-function relationships.

Main Results:

• The NONO-PSF heterodimer binds numerous expressed pri-miRNAs.
• NONO-PSF globally enhances pri-miRNA processing via the Drosha-DGCR8 Microprocessor.
• NEAT1 significantly impacts global pri-miRNA processing.
• NEAT1 recruits the NONO-PSF heterodimer and other RBPs, with specific RNA elements attracting the Microprocessor.

Conclusions:

• The NONO-PSF heterodimer plays a global role in enhancing pri-miRNA processing.
• NEAT1 acts as a scaffold, organizing RBPs and pri-miRNAs to facilitate efficient miRNA biogenesis.
• A 'bird nest' model is proposed where NEAT1 orchestrates nuclear miRNA processing.