Cell Rep. 2024 Jun 5;43(6):114331. doi: 10.1016/j.celrep.2024.114331

The evolutionarily conserved choroid plexus contributes to the homeostasis of brain ventricles in zebrafish

Inyoung Jeong¹, Søren N Andreassen², Linh Hoang³, Morgane Poulain⁴, Yongbo Seo⁵, Hae-Chul Park⁵, Maximilian Fürthauer⁴, Nanna MacAulay², Nathalie Jurisch-Yaksi⁶

Affiliations
¹Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, Erling Skjalgsons Gate 1, 7491 Trondheim, Norway.
²Department of Neuroscience, University of Copenhagen, Blegdamsvej 3, 2200 Copenhagen, Denmark.
³Cellular and Molecular Imaging Core Facility (CMIC), Norwegian University of Science and Technology, Erling Skjalgsons Gate 1, 7491 Trondheim, Norway.
⁴Université Côte d’Azur, CNRS, Inserm, iBV, 28 Avenue Valrose, 06108 Nice cedex 2, France.
⁵Department of Biomedical Sciences, Korea University College of Medicine, Seoul 02841, Republic of Korea.
⁶Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, Erling Skjalgsons Gate 1, 7491 Trondheim, Norway.

Abstract

The choroid plexus (ChP) produces cerebrospinal fluid (CSF). It also contributes to brain development and serves as the CSF-blood barrier. Prior studies have identified transporters on the epithelial cells that transport water and ions from the blood vasculature to the ventricles and tight junctions involved in the CSF-blood barrier. Yet, how the ChP epithelial cells control brain physiology remains unresolved. We use zebrafish to provide insights into the physiological roles of the ChP. Upon histological and transcriptomic analyses, we identify that the zebrafish ChP is conserved with mammals and expresses transporters involved in CSF secretion. Next, we show that the ChP epithelial cells secrete proteins into CSF. By ablating the ChP epithelial cells, we identify a reduction of the ventricular sizes without alterations of the CSF-blood barrier. Altogether, our findings reveal that the zebrafish ChP is conserved and contributes to the size and homeostasis of the brain ventricles.

DOI: 10.1016/j.celrep.2024.114331