Ambient effects on neural stem cells: Insights from Drosophila

Neural stem cells (NSCs) play a fundamental role in generating diverse neuronal populations that contribute to the formation of intricate neural circuitry. Disturbances arising from intrinsic or extrinsic factors can alter the developmental behavior of NSCs and disrupt nervous system homeostasis. While intrinsic regulatory mechanisms have been elucidated extensively in invertebrate or vertebrate models, the regulatory mechanisms underlying extrinsic cues from the cellular environment remain poorly understood. This review synthesized recent research on cellular ambient effects, including the microenvironment, systemic environment and external factors, on NSCs in Drosophila . Key topics include spatial cues, NSC-glia interactions, long-distance regulation by tissues such as the fat body, and the external environmental stressors like irradiation or viral infection. By integrating these findings, this review provides new insights into how extrinsic signals shape NSCs and bridges gaps between foundational research and clinical translation.