Pluto Bioinformatics

GSE144587: A subpopulation of Periostin-expressing fibroblasts is required for cardiac muscle and neuronal maturation after birth

Bulk RNA sequencing

During the postnatal period in mammals, the cardiac muscle transitions from hyperplasic to hypertrophic growth, the extracellular matrix (ECM) undergoes remodeling, and the heart loses regenerative capacity. While ECM maturation and crosstalk between cardiac fibroblasts (CFs) and cardiomyocytes (CM) have been implicated in neonatal heart development, not much is known about specialized fibroblast heterogeneity and functions in the early postnatal period. In order to better understand CF functions in heart maturation and postnatal cardiomyocyte cell cycle arrest, we have performed gene expression profiling and ablation of postnatal CF subpopulations. Fibroblast lineages expressing Tcf21 or Periostin were traced in transgenic GFP reporter mice and their biological functions and transitions during the postnatal period were examined in sorted cells using RNAseq. A subpopulation of highly proliferative Periostin (Postn)+ CFs was found from postnatal day (P)1 to P11 but was not detected at P30. This population was less abundant and transcriptionally different from Tcf21+ resident CFs, which persist in the mature heart. The Postn+ subpopulation preferentially expresses genes related to cell proliferation and neuronal development, while Tcf21+ CFs differentially express genes related to ECM maturation at P7 and immune crosstalk at P30. Ablation of the Postn+ CFs from P0 to P6 led to altered cardiac sympathetic nerve patterning and a reduction in CM binucleation, maturation, and hypertrophic growth. Thus, postnatal CFs are heterogeneous and include a transient proliferative Postn+ subpopulation required for cardiac nerve development and cardiomyocyte maturation soon after birth. SOURCE: KATHERINE YUTZEY (katherine.yutzey@cchmc.org) - CINCINNATI CHILDREN'S HOSPITAL