Division of Nephrology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
Department of Biochemistry and Cell Biology, School of Medicine, Kyungpook National University, Taegu, Republic of Korea.
Biochimie. 2021 Sep;188:52-60. doi: 10.1016/j.biochi.2021.04.006. Epub 2021 Apr 21.
Aquaporins (AQPs) are water channel proteins facilitating passive transport of water and other small molecules across biomembranes. Regulation of osmotic homeostasis via AQPs is accompanied by dynamic participation of various cellular signaling pathways. Recently emerging evidence reveals that functional roles of AQPs are further extended from the osmotic regulation via water permeation into the cell proliferation and differentiation. In particular, anomalous expression of AQPs has been demonstrated in various types of cancer cells and cancer stem-like cells and it has been proposed as markers for proliferation and progression of cancer cells. Thus, a more comprehensive view on AQPs could bring a great interest in the cell stemness accompanied by the expression of AQPs. AQPs are broadly expressed across tissues and cells in a cell type- and lineage-specific manner during development via spatiotemporal transcriptional regulation. Moreover, AQPs are expressed in various adult stem cells and cells associated with a stem cell niche as well as cancer stem-like cells. However, the expression and regulatory mechanisms of AQP expression in stem cells have not been well understood. This review highlighted the AQPs expression in stem cell niches/stem cells and the involvement of AQPs in the cell proliferation and signaling pathways associated with cell stemness.
水通道蛋白（AQP）是一种促进生物膜被动转运水和其他小分子的水通道蛋白。AQP 通过调节渗透平衡，伴随各种细胞信号通路的动态参与。最近出现的证据表明，AQP 的功能作用进一步从水渗透的渗透调节扩展到细胞增殖和分化。特别是，AQP 在各种类型的癌细胞和癌症干细胞样细胞中的异常表达已经被证明，并被提议作为癌细胞增殖和进展的标志物。因此，对 AQP 的更全面的认识可能会对伴随 AQP 表达的细胞干性产生极大的兴趣。AQP 在发育过程中通过时空转录调控，以细胞类型和谱系特异性的方式广泛表达于组织和细胞中。此外，AQP 还在各种成体干细胞以及与干细胞龛相关的细胞和癌症干细胞样细胞中表达。然而，AQP 在干细胞中的表达和调控机制尚不清楚。本综述强调了 AQP 在干细胞龛/干细胞中的表达以及 AQP 在与细胞干性相关的细胞增殖和信号通路中的参与。
