Team:QHFZ-China/Future
_FUTURE_
Part 1: Uric acid (UA) degradation Firstly, we will optimize the sequence of the parts. For mUTS and HucO, the optimization will lower the background expression and improve the sensitivity to UA. The thresholds of the UA concentration to start UOX expression will be changed to any value to satisfy specific users' demands. For smUOX-Flag, the optimization will be done to increase the efficiency of secretion, so that more smUOX will be sent out of cells to degrade UA. At the same time, we will also introduce a UOX-Flag that cannot be secreted to meet the requirement of users who are allergic to UOX. Secondly, we will use genetically enhanced stem cells [1] to replace HeLa cells, and use stable transfection technique with the aid of CRISPR/Cas9 system to replace transient transfection technique. Notably, during the interview to Haoyi Wang, we knew that in the future, scientists will develop pluripotent stem cells with any possible matches, which means we will no longer need to use patients’ cells to develop iPS cells. We will add a biosafety module [2] and differentiate the stem cells into a safe cell type. At last, we will make a micro organ by the cells, load it into a room made by bio-friendly material. The organ then can be transplanted into the human body. The concept map is as the following:
Part 2: UA detection Firstly, we will optimize the sequence of the parts to make the gene circuit has a lower background, a more sensitive and rapider response to UA and a higher output. Then we will change or optimize the plasmid backbones, condition of culture, components of broth, condition of UA induction to make the response to UA more sensitive, rapider and more stable in independent repeat tests. We have got many possible optimization plan in the literatures and during human practices. At last, we will make a cell-free system to make the UA biosensor more stable and safer for users [3]. At that time, we will compare the system to the UA detector and test paper in sale. Secondly, we will finish building our hardware and improve it. The hardware will not only tell the fluorescence and the UA concentration of the sample, but can also automatically add the sample of specific volume to the reaction system, shake the tube at specific temperature. The design is realizable because iGEM team Valencia UPV 2018 has contributed a lot at such hardware . In addition, the method can also be used in hospital. To this end, the requirements are more or less different from that of a home device：accuracy is more important than any other futures. We will try to improve our system based on the application scenario. What’s more, the uric-acid-responsive regulatory system is also useful in synthetic biology. UA cannot be degraded by various microorganisms and does not influence most gene circuit, which is obviously better than some common inducers, such as arabinose, lactose, etc. We will try to study the application in this field.
Part 3: An ultimately vision Homeostasis is very important for human health. UA is only a part of human homeostasis. Here, we use UA regulation as a proof of concept. However, what we want to achieved by cell therapy is to maintain the homeostasis. We will introduce a micro organ that can control many parts about homeostasis. As people’s life prolongs and people has more requirement for health, implanting auxiliary components in body becomes a tendency. For example, pacemaker, heart stent and chip. Our assumptive replaceable homeostasis control organ will not only be helpful for the patients, but also meaningful for healthy people to alleviate the burden of their organs. To this end, more high-efficiency gene related circuits should be developed and we are looking forward to it.
[1] Yang, J., J. Li, K. Suzuki, X. Liu, J. Wu, W. Zhang, R. Ren, W. Zhang, P. Chan, J.C. Izpisua Belmonte, J. Qu, F. Tang, and G.H. Liu, Genetic enhancement in cultured human adult stem cells conferred by a single nucleotide recoding. Cell Res, 2017. 27(9): p. 1178-1181. [2] Di Stasi, A., S.K. Tey, G. Dotti, Y. Fujita, A. Kennedy-Nasser, C. Martinez, K. Straathof, E. Liu, A.G. Durett, B. Grilley, H. Liu, C.R. Cruz, B. Savoldo, A.P. Gee, J. Schindler, R.A. Krance, H.E. Heslop, D.M. Spencer, C.M. Rooney, and M.K. Brenner, Inducible apoptosis as a safety switch for adoptive cell therapy. N Engl J Med, 2011. 365(18): p. 1673-83. [3] Huang, A., P.Q. Nguyen, J.C. Stark, M.K. Takahashi, N. Donghia, T. Ferrante, A.J. Dy, K.J. Hsu, R.S. Dubner, K. Pardee, M.C. Jewett, and J.J. Collins, BioBits Explorer: A modular synthetic biology education kit. Sci Adv, 2018. 4(8): p. eaat5105.
