miR-195 competes with HuR to modulate stim1 mRNA stability and regulate cell migration

Area of Science:

• Cell Biology
• Molecular Biology
• Biochemistry

Background:

• Stromal interaction molecule 1 (Stim1) is crucial for store-operated calcium entry (SOCE) and intestinal epithelial repair.
• Mechanisms controlling Stim1 expression, particularly post-transcriptional regulation, are not well understood.

Purpose of the Study:

• To elucidate the post-transcriptional mechanisms regulating Stim1 expression.
• To identify factors that associate with the stim1 3'-untranslated region (3'-UTR) and influence Stim1 mRNA stability.

Main Methods:

• Investigated the interaction of microRNA-195 (miR-195) and HuR with the stim1 3'-UTR.
• Assessed the impact of miR-195 and HuR on stim1 mRNA decay and stability.
• Examined the effects of manipulating miR-195 and HuR levels on Stim1 expression and cell migration in wound healing models.

Main Results:

• miR-195 and HuR compete for binding to the stim1 3'-UTR.
• miR-195 binding destabilizes stim1 mRNA, promoting its decay, while HuR binding enhances mRNA stability.
• Overexpression of miR-195 reduced Stim1 levels and inhibited wound-induced cell migration, effects rescued by HuR.

Conclusions:

• Stim1 expression is controlled by a post-transcriptional mechanism involving the interplay between miR-195 and HuR.
• This regulatory axis fine-tunes Stim1 levels and influences critical cellular processes like epithelial repair.