The proper balance between symmetric and asymmetric stem cell division is crucial both to maintain a population of stem cells and to prevent tumorous overgrowth. Neural stem cells in the Drosophila optic lobe originate within a polarised neuroepithelium, where they divide symmetrically. Neuroepithelial cells are transformed into asymmetrically dividing neuroblasts in a precisely regulated fashion. This cell fate transition is highly reminiscent of the switch from neuroepithelial cells to radial glial cells in the developing mammalian cerebral cortex. To identify the molecules that mediate the transition, we microdissected neuroepithelial cells and compared their transcriptional profile with similarly obtained optic lobe neuroblasts. We find genes encoding members of the Notch pathway expressed in neuroepithelial cells. We show that Notch mutant clones are extruded from the neuroepithelium and undergo premature neurogenesis. A wave of proneural gene expression is thought to regulate the timing of the transition from neuroepithelium to neuroblast. We show that the proneural wave transiently suppresses Notch activity in neuroepithelial cells, and that inhibition of Notch triggers the switch from symmetric, proliferative division, to asymmetric, differentiative division.
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http://dx.doi.org/10.1242/dev.051250 | DOI Listing |
Commun Biol
December 2024
Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610213, China.
Mammals suffer permanent hearing impairment from the loss of auditory hair cells due to their inability to regenerate. In contrast, lower vertebrates exhibit extraordinary capacity for hair cell regeneration and hearing restoration, but the mechanisms remain unclear. Here we characterize the single-cell atlas of Xenopus laevis inner ear and perform a comprehensive comparison with mouse model.
View Article and Find Full Text PDFTransl Cancer Res
November 2024
Department of Pharmacy, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China.
Background: High incidence and mortality rates underscore lung cancer as a significant global health issue. Understanding the molecular mechanisms driving its progression is crucial for developing effective treatments. This study explores a potential molecular regulator that may contribute to the progression of non-small cell lung cancer (NSCLC) by utilizing bioinformatics analyses and laboratory experiments, aiming to provide insights that could inform future therapeutic strategies.
View Article and Find Full Text PDFAdv Sci (Weinh)
December 2024
Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin, 300072, China.
Integrated biochemical and biophysical signals regulate embryonic development. Correct neural tube formation is critical for the development of central nervous system. However, the role of microgravity in neurodevelopment and its underlying molecular mechanisms remain unclear.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
December 2024
Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine, University of Southern California, Los Angeles CA 90033.
Pediatr Dev Pathol
December 2024
Department of Pathology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.
Tumors are increasingly defined by molecular alterations but approach to cases with discordant histologic and molecular features is unclear. Myxoid glioneuronal tumor (MGNT), histologically similar to dysembryoplastic neuroepithelial tumor (DNET), is characterized by dinucleotide mutations in gene (K385L or K385I). Here, we report K385L mutation in a neonatal high-grade glioma.
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