Mechanisms that maintain cilia orientation and membrane independence in mammalian tracheal epithelial cells and olfactory neurons elucidated

December 4, 2025

Summary of the announcement

An international joint research group led by Graduate Student Keishi Sakai of the Tokyo University of Agriculture and Technology Graduate School Graduate School of Engineering Department of Biotechnology and Life Science (at the time of research: currently Assistant Professor) and Professor Kyosuke Shinohara of the Graduate School of Institute of Engineering Division of Biotechnology and Life Science of the same university have investigated the development of Tppp3 (Tubulin Polymerization Promoting in mammalian model mice) Protein Family Member 3) By analyzing the function of genes, we have clarified the mechanism by which ciliary cells in the tracheal epithelium and olfactory epithelium tissues acquire precise orientation and independence of ciliary membrane structure, which were previously unknown. This mechanism allows cilia to grow in the right direction and perform various functions. This result is expected to lead to the elucidation of the mechanism by which respiratory abnormalities and olfactory disorders are caused in the future.

The results of this research were published in the December 1st issue of the Proceedings of the National Academy of Sciences (PNAS).
Title of the paper: Tppp3 determines basal body positioning and identity of respiratory cilia via microtubule assembly and sphingolipid homeostasis
URL: https://doi.org/10.1073/pnas.2503931122

Figure 1: Role of Tppp3 protein in tracheal and olfactory epithelial tissues. Tppp3 is responsible for the formation of microtubule structures within tracheal motile ciliated cells (top) and olfactory neurons (bottom), thereby controlling cilia orientation, membrane independence, and centrosome positioning. Genetically engineered mice lacking the Tppp3 gene exhibit phenotypes of coughing, sneezing, and olfactory impairment.

For more details, please see below.

[Press release dated December 4, 2025] Mechanisms maintaining cilia orientation and membrane independence in mammalian tracheal epithelial cells and olfactory neurons elucidated