The Conserved Transcription Factor Krüppel Regulates the Survival and Neurogenesis of Mushroom Body Neuroblasts inDrosophilaAdult Brains

Abstract

SummaryIn various metazoans, includingDrosophilaand humans, neural progenitors exit the cell cycle and are eliminated by the end of development, limiting adult neurogenesis. We demonstrate that inDrosophila,the conserved transcription factorKrüppel(Kr) controls neurogenic capacity of a specific subset of neuroblasts that forms the mushroom body (MBNBs), analogous to the mammalian hippocampus. TheIrregular facetmutation, which altersKrexpression, and neuroblast-specific Kr depletion allow MBNBs, but not other neuroblasts, to persist beyond development and generate neurons in adult brains. Persisting MBNBs express Imp, an RNA-binding protein that promotes neuroblast proliferation and survival. Our results underscore a critical role for Kr in the developmental control of a specific progenitor population, uncovering a novel mechanism controlling adult neurogenesis.