A research group led by Assistant Professor Kiyoka Wakayama of the Faculty of Life and Environmental Sciences, University of Yamanashi, and Professor Teruhiko Wakayama of the Developmental Engineering Research Center has produced a large number of freeze-dried sperms from mice subjected to temperature-load treatment from -196 ° C to 150 ° C by microinsemination. I succeeded in getting a baby.
Resistance to extreme environments such as hot / cold and vacuum has been found not only in archaea and yeast, but also in lower animals such as tardigrades and chironomids.These organisms acquire extreme tolerance by becoming dry sleep (a state in which most of the water is discharged from the body), and can sustain life until the environment improves.On the other hand, many higher animals cannot survive in extreme conditions because intracellular water crystallizes at low temperatures and protein heat denaturation occurs at high temperatures.Therefore, it has been considered that mammals including human beings are not extremely resistant.
Therefore, this time, the research group artificially created a state similar to tardigrade by freeze-drying mouse sperm, and gave freeze-dried sperm a temperature change of ultra-low temperature or high temperature.When microinsemination was performed using this sperm, we succeeded in obtaining a large number of offspring, and it is clear that even in mammals, the nucleus has a strong temperature tolerance comparable to that of lower animals. became.
This resistance ability is a very important discovery in that it can safely store mammalian gene resources for a long period of time, and in the future, it is a technology that can semi-permanently store mammalian gene resources like plant seeds. Expected to lead to development.
Paper information:[Scientific Reports] Tolerance of the freeze-dried mouse sperm nucleus to temperatures ranging from –196 ° C to 150 ° C