PREGNANCY-RESPONSIVE POOLS OF ADULT NEURAL STEM CELLS FOR TRANSIENT NEUROGENESIS IN MOTHERS

Adult neural stem cells (NSCs) contribute to lifelong brain plasticity. In the adult mouse ventricular-subventricular zone, NSCs are heterogeneous and, depending on their location in the niche, give rise to different subtypes of olfactory bulb (OB) interneurons. Here we show that multiple regionally-distinct NSCs, including domains that are usually quiescent, are recruited on different gestation days during pregnancy. Synchronized activation of these adult NSC pools generates transient waves of short-lived OB interneurons, especially in layers with less neurogenesis under homeostasis. Using spatial transcriptomics, we identify molecular markers of pregnancy-associated interneurons, and show that some subsets are temporarily needed for own pup recognition. Thus, pregnancy triggers transient, yet behaviorally-relevant neurogenesis, highlighting the physiological relevance of adult stem cell heterogeneity. Overall design: Comparative analysis between four mouse brain samples; (i) one mother during perinatal care, (ii) one mother at peri-weaning, (iii) two age-matched virgins, was performed with the 10x Genomics Visium platform for fresh frozen samples. Spatial transcriptome analysis focused on the differential gene expression across these states and was performed both globally and also stratified within the corresponding spot clusters.