Figure 8. Schematic representation of transcriptomic and phenotypic changes occurring during postnatal β-cell maturation.

Weaning coincides with major modifications of microRNA and mRNA expression in pancreatic islets. The decrease of miR-17-5p and miR-181b-5p and the concomitant increase of miR-29b-3p are inversely correlated with expression changes of directly and indirectly targeted genes essential to achieve full β-cell maturation (highlighted). These modifications allow the acquisition of glucose-induced insulin secretion (GSIS) and reduce β-cell proliferation to define the size of the adult β-cell mass.