Stabilization of insect cell membranes and soluble enzymes by accumulated cryoprotectants during freezing stress

0561779 - BC 2023 RIV US eng J - Článek v odborném periodiku
Grgac, Robert - Rozsypal, Jan - Des Marteaux, Lauren - Štětina, T. - Košťál, Vladimír
Stabilization of insect cell membranes and soluble enzymes by accumulated cryoprotectants during freezing stress.
Proceedings of the National Academy of Sciences of the United States of America. Roč. 119, č. 41 (2022), č. článku e2211744119. ISSN 0027-8424. E-ISSN 1091-6490
Grant CEP: GA ČR(CZ) GA19-13381S
Institucionální podpora: RVO:60077344
Klíčová slova: cryopreservation * freeze tolerance * protein stabilization
Obor OECD: Biology (theoretical, mathematical, thermal, cryobiology, biological rhythm), Evolutionary biology
Impakt faktor: 11.1, rok: 2022
Způsob publikování: Open access
https://www.pnas.org/doi/epdf/10.1073/pnas.2211744119

Most multicellular organisms are freeze sensitive, but the ability to survive freezing of the extracellular fluids evolved in several vertebrate ectotherms, some plants, and many insects. Here, we test the coupled hypotheses that are perpetuated in the literature: that irreversible denaturation of proteins and loss of biological membrane integrity are two ultimate molecular mechanisms of freezing injury in freeze-sensitive insects and that seasonally accumulated small cryoprotective molecules (CPs) stabilize proteins and membranes against injury in freeze-tolerant insects. Using the drosophilid fly, Chymomyza costata, we show that seven different soluble enzymes exhibit no or only partial loss of activity upon lethal freezing stress applied in vivo to whole freeze-sensitive larvae. In contrast, the enzymes lost activity when extracted and frozen in vitro in a diluted buffer solution. This loss of activity was fully prevented by adding low concentrations of a wide array of different compounds to the buffer, including C. costata native CPs, other metabolites, bovine serum albumin (BSA), and even the biologically inert artificial compounds HistoDenz and Ficoll. Next, we show that fat body plasma membranes lose integrity when frozen in vivo in freeze-sensitive but not in freeze-tolerant larvae. Freezing fat body cells in vitro, however, resulted in loss of membrane integrity in both freeze-sensitive and freeze-tolerant larvae. Different additives showed widely different capacities to protect membrane integrity when added to in vitro freezing media. A complete rescue of membrane integrity in freeze-tolerant larvae was observed with a mixture of proline, trehalose, and BSA.
Trvalý link: https://hdl.handle.net/11104/0341333