The zinc finger protein Zfpm1 modulates ventricular trabeculation through Neuregulin-ErbB signalling.

Ventricular trabeculation is one essential step for generating a functionally competent ventricular wall, while how the early trabeculae carneae forms and subsequently develops into mature chambers is poorly understood. We found that in zebrafish zfpm1-/- juvenile, cardiac function is significantly compromised, with hearts exhibiting deformed trabecular meshwork. To elucidate the mechanisms of Zfpm1 function in cardiac trabeculation, we analyzed zfpm1 mutant hearts more closely and found that loss of Zfpm1 activity resulted in over-activation of Neuregulin-ErbB signalling and abnormally elevated cardiomyocyte proliferation during cardiac trabeculae growth and modeling stages. These results implicate Zfpm1 plays a pivotal role in coordinating trabeculae patterning and growth.