Dynamic alternative polyadenylation during iPSC differentiation into cardiomyocytes

Area of Science:

• Molecular Biology
• Genetics
• Developmental Biology

Background:

• Alternative polyadenylation (APA) is a crucial post-transcriptional regulatory mechanism in eukaryotes.
• APA is linked to various traits and diseases, but its role in cell differentiation is poorly understood.

Purpose of the Study:

• To systematically characterize APA profiles during induced pluripotent stem cell (iPSC) to cardiomyocyte differentiation.
• To identify dynamic APA patterns and regulatory factors involved in this process.

Main Methods:

• Analysis of RNA-seq data from 16 time points of iPSC to cardiomyocyte differentiation.
• Fuzzy c-means clustering to identify APA patterns.
• Linear mixed-effects modeling to determine regulatory roles of genes like TIA1.
• Construction of a miRNA-APA interaction network.

Main Results:

• Identified 950 differential APA events and five distinct dynamic APA patterns.
• 3'UTR progressive lengthening was the predominant pattern, with associated genes enriched in cell cycle and mRNA metabolism pathways.
• TIA1 was identified as a key regulator of APA events, including those affecting cardiac function.
• Another APA pattern showed rapid response to stimuli, causing 3'UTR shortening.
• A miRNA-APA network revealed potential hub miRNAs regulating cardiomyocyte differentiation.

Conclusions:

• The study reveals complex APA mechanisms governing iPSC to cardiomyocyte differentiation.
• Findings provide insights into APA regulation and its role in cell differentiation, particularly in cardiac development.
• Identified TIA1 and specific miRNAs as key players in regulating APA during cardiomyocyte differentiation.