ELAVL1 modulates transcriptome-wide miRNA binding in murine macrophages

Area of Science:

• Molecular Biology
• Gene Regulation
• Immunology

Background:

• Posttranscriptional gene regulation by microRNAs (miRNAs) and RNA binding proteins (RBPs) is crucial for cellular processes.
• The interplay between specific miRNAs and RBPs, such as ELAVL1 (HuR), remains incompletely understood.
• Macrophages play key roles in inflammation, angiogenesis, and tissue homeostasis.

Purpose of the Study:

• To investigate the functional interaction between the RBP ELAVL1 (HuR) and miRNAs.
• To elucidate the role of ELAVL1 in modulating miRNA binding and gene expression in macrophages.
• To understand ELAVL1's contribution to angiogenesis via miRNA antagonism.

Main Methods:

• Transcriptome-wide mapping of miRNA binding sites in wild-type and Elavl1 knockout murine bone-marrow-derived macrophages.
• Analysis of ELAVL1 proximity effects on miRNA binding and gene expression.
• Investigation of the miR-27/ELAVL1/ZFP36 regulatory axis.

Main Results:

• ELAVL1 binding near miRNA sites attenuated miRNA binding and increased gene expression.
• ELAVL1 promotes angiogenesis, partly by antagonizing miRNA function.
• ELAVL1 antagonized miR-27 binding to Zfp36 mRNA, reducing ZFP36 suppression.

Conclusions:

• ELAVL1 antagonizes miRNA activity, thereby promoting angiogenesis.
• The miR-27-ELAVL1-ZFP36 pathway synchronizes the expression of these key regulatory molecules.
• This study provides a valuable resource for studying posttranscriptional regulation in macrophages.