Zbtb16 determines the fate plasticity of cardiovascular progenitors through IGF2BP3-mediated mRNA stabilization [scRNA-seq]

Cardiovascular progenitors (CPs) are responsible for generating the diverse cell populations in hearts, exhibiting significant transcriptional heterogeneity. However, the regulation of fate plasticity among heterogeneous CP subpopulations, as well as the intrinsic regulatory factors, remains poorly understood. In this study, we characterized three CP subpopulations derived from pluripotent stem cells and found that the deletion of ZBTB family protein Zbtb16 led to a profound imbalance in the branching transition trajectory of Early-CPs, redirecting them toward CPs committed to endothelial cells and cardiac fibroblasts (EC/CF-CPs) rather than that to cardiomyocytes (CM-CPs). Mechanistic studies revealed that Zbtb16 interacted with the m6A reader IGF2BP3 to post-transcriptionally recognize and stabilize the mRNAs of key genes critical for the CM-CP subpopulation determination. Collectively, our findings established Zbtb16 as a key regulator of fate plasticity of heterogeneous CP subpopulations and revealed the interplay with IGF2BP3 to impact the m6A-modified mRNA stabilization, which provided new insights into the intrinsic connections between CP subpopulation plasticity and cardiovascular multi-lineage fate determination. To investigate the subpopulation regulated by Zbtb16 at CP stage, samples from day 6 of cardiomyocyte differentiation in the D3-Ctrl and Zbtb16-KO groups were collected and analyzed by scRNA-seq.