Platr4 is an ESC-specific lncRNA that exhibits its function downstream on meso/endoderm lineage commitment

The mammalian genome encodes thousands of long non-coding RNAs (lncRNAs) that are developmentally regulated and differentially expressed across tissues, suggesting possible roles in cellular differentiation. Despite this expression pattern, little is known about how lncRNAs influence lineage commitment at the molecular level. Here, we reveal that perturbation of an embryonic stem cell (ESC)-specific lncRNA, Pluripotency associated transcript 4 (Platr4), in ESCs directly influences the downstream meso/endoderm differentiation program without affecting pluripotency. We further show that Platr4 interacts with the TEA domain transcription factor 4 (Tead4) to regulate the expression of a downstream target gene crucial in the cardiac lineage program known as connective tissue growth factor (Ctgf). Importantly, Platr4 knockout mice exhibit myocardial atrophy, valve mucinous degenration associated with reduced cardiac output and sudden heart failure. Together, our findings provide evidence that Platr4 expression in undifferentiated ESCs is critical for downstream lineage differentiation, highlighting its importance in disease modeling and regenerative medicine. ### Competing Interest Statement The authors have declared no competing interest.