Year: 2025
Type: article
Abstract: The choroid plexus (ChP) epithelium secretes cerebrospinal fluid (CSF) and signaling factors that influence brain development. In addition to classical secretory pathways, the ChP also employs apocrine secretion, in which large cytoplasmic portions bud from the apical surface in structures called aposomes. Although historically underappreciated, recent imaging and molecular studies demonstrate that this process is calcium-dependent and regulated by neuromodulators such as serotonin. Apocrine secretion contributes distinct cytoplasmic cargo-proteins, organelles, and signaling molecules-to the CSF, with evidence for developmental roles in neurogenesis and progenitor cell differentiation. This review synthesizes structural, functional, and proteomic data supporting ChP apocrine secretion, compares it to other epithelial release mechanisms, and highlights outstanding questions about its regulation and physiological roles. By focusing on this unconventional and understudied mode of secretion, we provide a framework for understanding how ChP-mediated cargo release shapes the CSF environment and contributes to brain development.
Source: Fluids and Barriers of the CNS
Authors: Ya’el Courtney, Maria K. Lehtinen
Institutions: Boston Children's Hospital, Harvard University
Language: English
Subfield: Cellular and Molecular Neuroscience
Field: Neuroscience
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $3,390
Funders: National Science Foundation, Howard Hughes Medical Institute, New York Stem Cell Foundation, Harvard University, Simons Foundation Autism Research Initiative, National Institutes of Health, Intellectual and Developmental Disabilities Research Center, National Institute on Drug Abuse, National Institute of Neurological Disorders and Stroke, Eunice Kennedy Shriver National Institute of Child Health and Human Development
OpenAlex ID: W4412475755