Zijl Sebastiaan, Hiratsuka Toru, Mobasseri Atefeh, Ebrahimkutty Mirsana, Börmel Mandy, Garcia-Manyes Sergi, Watt Fiona M
Centre for Gene Therapy and Regenerative Medicine, King's College London, 28th Floor, Tower Wing, Guy's Hospital, Great Maze Pond, London SE1 9RT, UK.
Department of Molecular Oncology, Graduate School of Medicine, Osaka University, Osaka 541-8567, Japan.
J Cell Sci. 2025 Sep 1;138(17). doi: 10.1242/jcs.264242. Epub 2025 Sep 8.
To gain insights into the human epidermal stem cell niche, we have previously identified micron-scale topographical substrates that regulate differentiation of spread keratinocytes. On one substrate (S1), cells interact with circular topographies and differentiation is stimulated; on the other (S2), cells interact with triangular topographies and differentiation is inhibited. Cell stiffness on S1 and S2 was similar, and nuclear localisation of the mechano-sensitive transcriptional regulator YAP1 was decreased on S1 and S2 compared to on flat substrates. However, cells on S2 exhibited reduced cell volume, leading us to explore the potential for volume-regulated differentiation. Treatment with polyethylene glycol decreased cell volume and inhibited differentiation under a range of conditions. Conversely, deionized water increased cell volume and stimulated differentiation. Bulk RNA sequencing identified several substrate-responsive genes, including aquaporins and ion channels. A membrane permeable Ca2+ chelator and an inhibitor of the water channel aquaporin 3 blocked volume-induced differentiation. These studies identify cell volume as a mechanism by which keratinocyte-niche interactions regulate terminal differentiation.
为深入了解人类表皮干细胞生态位，我们之前已鉴定出可调节铺展角质形成细胞分化的微米级地形底物。在一种底物（S1）上，细胞与圆形地形相互作用，分化受到刺激；在另一种底物（S2）上，细胞与三角形地形相互作用，分化受到抑制。S1和S2上细胞的硬度相似，与在平坦底物上相比，机械敏感转录调节因子YAP1在S1和S2上的核定位降低。然而，S2上的细胞体积减小，这促使我们探索体积调节分化的可能性。聚乙二醇处理在一系列条件下减小了细胞体积并抑制了分化。相反，去离子水增加了细胞体积并刺激了分化。大量RNA测序鉴定出了几个底物反应基因，包括水通道蛋白和离子通道。一种膜通透性Ca2+螯合剂和水通道水通道蛋白3的抑制剂阻断了体积诱导的分化。这些研究确定细胞体积是角质形成细胞与生态位相互作用调节终末分化的一种机制。
