Single-cell transcriptomics of neonatal mouse anterior pituitary in steady-state conditions and after transgenically inflicted local damage. Single-cell transcriptomics of neonatal mouse anterior pituitary in steady-state conditions and after transgenically inflicted local damage

The mouse pituitary gland undergoes vivid maturation immediately after birth. During this process, the local stem cell compartment shows signs of activation including elevated abundance and expression of stemness pathways when compared to adult pituitary stem cells. In addition, we found that the neonatal pituitary displays high regeneration efficiency, as occurring following diphtheria toxin (DT)-triggered endocrine cell-ablation injury using the GHCre/iDTR mouse model (expressing Cre recombinase under control of the growth hormone (Gh) promoter, as well as Cre-inducible (floxed) DT receptor (iDTR)). This regeneration is more pronounced than in older mice, which is in line with the activated (stem cell) nature of the neonatal gland. However, it is not known what molecular mechanisms underlie the stem cell activation status in the neonatal gland. Here, we set out to decode the stem cells’ phenotype during the neonatal pituitary maturation stage starting from single cell RNA-sequencing (scRNA-seq) interrogations of neonatal (postnatal day 7, PD7) normal (undamaged) and damaged pituitary (more specifically, its major endocrine anterior lobe).