Share with friends and circle of friends with wechat scanning QR code < / P > < p > < p > surging news chief reporter he Liping < / P > < p > human eyes can see all kinds of colors in the visible light band, and ears can hear sounds in the frequency range of 20-20000 Hz, but we still don't know whether we have the sense to sense the earth's magnetic field, which is a complete mystery < p > there are 6 corresponding authors in this study, one of them is Xie can, a researcher from the high intensity magnetic field science center of Hefei Institute of material sciences, Chinese Academy of Sciences, which is the common communication unit. Xie can's laboratory, together with the team of Oldenburg University, successfully prepared the cry protein of European robins, a night migratory bird with biological activity, in the laboratory for the first time, which laid the foundation for the success of the whole research < p > Xie can is receiving the surging news（ www.thepaper.cn ）In an interview, the reporter said that the multi-party cooperation started in 2016 is only the first stage of the research on biological magnetic induction in various laboratories, "this article is also the first stage of our long-term cooperation." There is still a lot of work to be explored by its laboratory and partners in the future < p > the research team systematically and completely summarized the basic principles and supporting evidence of the free radical pair hypothesis from the aspects of physics, chemistry and biology < p > compared with the previous theoretical research, this multi-party cooperative research took the European Robin's cryptochrome 4 protein as the main research object, carried out a series of high-precision spectroscopy tests, and carried out computational biology simulation, realized the mutual verification of theory and experiment. This is the first comprehensive explanation of the photochemical magnetic sensitivity of free radicals in nocturnal migratory cryptochrome proteins, which confirms and improves the mechanism of magnetic induction by free radicals, and provides an important basis for further explanation of migratory geomagnetic orientation behavior < p > functional cry4 protein from migratory birds. In theory, under blue light, the information of external magnetic field can be transformed into the change of quantum yield of photoinduced free radical pairs in cryptochrome protein, which can be perceived by cells < p > it is worth mentioning that one of the reasons why the hypothesis of magnetic induction of free radicals has not been confirmed by experiments in birds since it was put forward in 1978 is that the recombinant expression of avian cryptochrome protein often loses its own function due to the wrong folding of the protein, and for cryptochrome, the key auxin fad is lost < p > "the biggest regret of the free radical hypothesis is that scientists have never been able to obtain experimental evidence of the magnetic sensitivity of cryptochrome protein in migratory birds. In the early attempts, some experiments were done with cryptochrome proteins from plants or non migratory animals in the laboratory, but as the most typical migratory animals, migratory birds, limited by the difficulty of purification of cryptochrome proteins from birds, have never been really studied. " Xie added < p > in this study, scientists finally obtained a functional FAD binding cryptochrome protein of migratory birds. Under the guidance of Xie can and mouritsen, Xu Jingjing expressed and purified cry4 protein of night migratory birds with biological activity by using the optimized cold shock protein expression system customized in the laboratory. Due to the presence of fad chromophore, the protein sample showed a beautiful and transparent yellow green color. Mass spectrometry analysis showed that the FAD binding rate of the protein was as high as 97%. It lays a foundation for the success of the whole research < p > the acquisition of cry4 protein in European robins is actually quite tortuous. Xie can told surging news reporters that as early as the beginning of the cooperation, that is, in April 2016, the original plan was for Xie can's laboratory to prepare protein in China, and then send it to the foreign cooperation team for the next test by air transportation < p > in previous studies on MAgr, Xie can has successfully expressed and purified MAgr and Cry proteins of homing pigeons (directional homing but non seasonal migratory birds), as well as their complexes However, the international transportation scheme is not feasible. Xie can clearly remembers that on June 9, 2016, his laboratory sent samples to Oxford University for experiment for the first time, but it was very difficult“ Long distance international transportation of protein samples requires that the protein be frozen first, and then thawed after arriving at the destination laboratory. At that time, we found a problem, whether it's cry protein, MAgr protein, or the complex of the two, all these proteins related to magnetic induction are very unstable, and extremely sensitive to temperature. During the freezing and thawing process, the activity of proteins is greatly reduced or even disappeared. " For cry4 protein in this study, after long-distance transportation and freeze-thaw process, the key fad subunit was dissociated from cry4 protein, and cry4 protein lost its activity < p > at that time, how to keep cry protein fresh was an urgent problem. Just at this time, Xu Jingjing is applying for visiting scholar of mouritsen laboratory. In November 2016, mouritsen put forward a proposal to let Xu Jingjing directly enter Xie can's laboratory to learn the whole set of protein expression and purification technology. Under the framework of cooperation, Xie can is very open, "this is also a good thing for us, because we also hope others can repeat our published articles." After more than two months of intensive "crash course", Xu Jingjing entered mouritsen laboratory < p > "it took about seven or eight months for Xu Jingjing to establish the whole system from scratch in mouritsen laboratory. The expression and purification of cry4 protein were perfectly repeated, and it also had good activity." After the completion of the key cornerstone work, hore and mouritsen could not hide their excitement. They expressed their excitement in the email sent to Xie can. At that moment, the three parties formally established a long-term cooperation“ The three of us have totally different backgrounds. Hore is a physicist, so he is mainly engaged in physical chemistry. Mouritsen is engaged in animal behavior and neurobiology. I am engaged in protein research, so each of us has his own strong points, which can complement each other. " Xie can described this tripartite cooperation in this way < p > in the next two years, Xu Jingjing usually finished protein preparation in the morning, then took the flight from Germany to Britain, arrived at Oxford University in the afternoon and went straight to the laboratory to test the performance of protein, that is, the magnetic sensitivity of free radical to photochemical reaction, together with the team members. Xie can once "experienced half a trip" during her visit to Oxford University, and "I can realize that she basically shuttled between the two countries for more than two years ?
2023-03-22 10:04:37