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Updated: Jun 11, 2025

Measuring the Osmotic Water Permeability Coefficient Pf of Spherical Cells: Isolated Plant Protoplasts as an Example
Published on: October 8, 2014
Heme-based aquareceptors
1Instytut Biologii Molekularnej i Biotechnologii, Wydział Biologii, Uniwersytet im. Adama Mickiewicza w Poznaniu.
Abstract:
How cells sense water is of fundamental importance in biology. Hygrosensation has been demonstrated in specialized sensory cells that sense extracellular moisture. Even in microorganisms, osmosensors do not sense water per se. Water-sensing mechanisms would have been necessary for organisms to migrate and survive in water-poor conditions and to evolve into multicellular organisms. Due to the potential ability of water molecules to bind to gas-binding sites in the heme-based sensing domains of gasoreceptors, I suggest that some of them could have a parallel role as protein aquareceptors. Just as gasoreceptors function in almost every cell, aquareceptors must also function in almost every cell. I think that aquareceptors must be present in the cell membrane, cytoplasm, and every organelle. I also wonder if hemoglobin could also be considered a putative aquareceptor.
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