2026-06-02 茨城大学
TisIBP8 による乾燥ストレス保護作用の模式図。高活性氷晶結合タンパク質 TisIBP8 を発現する線虫では、乾燥ストレス後の生存率が向上し、筋細胞の損傷や細胞膜構造の乱れが抑えられていることがわかった（WTは野生型線虫）。このことから、TisIBP8 は細胞膜を安定化することで、乾燥による細胞ダメージを軽減する可能性が示された。
＜関連情報＞
- https://www.ibaraki.ac.jp/news/n/2026/06/02014931.html
- https://febs.onlinelibrary.wiley.com/doi/10.1002/2211-5463.70274
過剰に活性化した氷結合タンパク質は、線虫Caenorhabditis elegansの細胞膜を安定化させ、脱水ストレスに対する耐性を向上させる Hyperactive ice-binding proteins stabilize cell membranes and improve resistance to dehydration stress in Caenorhabditis elegans
Daiki Shimose, Kotaro Ozaki, Ryohei Kuriyama, Yuka Ikemoto, Kazuhiro Mio, Yuji C. Sasaki, Tatsuya Arai, Sakae Tsuda, Yoichi Shinkai, Masahiro Kuramochi
FEBS Open Bio Published: 21 May 2026
DOI:https://doi.org/10.1002/2211-5463.70274
Abstract
Ice-binding proteins (IBPs) are known to modulate ice growth and promote freezing tolerance and have recently attracted attention due to their cell-protective functions under freezing or low-temperature conditions. In this study, we demonstrate that IBP expression improves resistance to dehydration stress in Caenorhabditis elegans. After 30 min of drying, transgenic worms expressing a high-activity fungal IBP (TisIBP8) showed a modest but significant increase in survival compared with wild-type worms. Furthermore, imaging revealed reduced muscle-cell damage in the TisIBP8-expressing worms while synchrotron radiation infrared microspectroscopy showed membrane structural changes during dehydration were attenuated by TisIBP8 expression. These findings suggest that IBPs exert protective effects by stabilizing cell membranes independent of ice binding, therefore broadening the potential applications of IBPs for biological preservation under nonfreezing stress conditions.
