Besides just exploring the design by ourselves, we also asked other teams--QHFZ and UCAS_China--for help. As an exchange, several experiments were conducted by us to provide useful results for them.
Through this process, we did not only obtain data or parts from other teams but also established a precious friendship. Therefore, to us, collaboration is one of the most important parts of our project. Specific experiences of collaboration with other teams are elaborated below.
Collaboration Project 1:
cooperated with QHFZ to measure the influence of heavy metal ions on organisms
We shared solution samples containing heavy metal ions with QHFZ. They conducted experiments with those samples to determine the harmfulness heavy metal ions have on organisms.
In the experiments, QHFZ used innocuous Ca and Mg ions as controls while potentially harmful Pb, Hg, and Cd ions as experimental groups. Those metal ions were added to mammalian cell culture mediums, and the reaction and growing conditions of these cells were recorded.
Through the experiment, they discovered that the three more potentially harmful heavy metal ions—Pb, Hg, and Cd ions—posed more threats to the growth of cells, especially Hg and Cd ions.
To some extent, the experiment verifies the harmfulness of heavy metal ions.
Figure 1: The effect of different heavy metal on cell growth（collabration with QHFZ）
Collaboration Project 2:
cooperated with QHFZ, using RinA_p80α amplifier to improve the efficiency of Hg Sensor
One of the most important parts of NEZHA is to use the Sensor to detect the concentrations of heavy metal ions in external environments. When developing an upgraded version of the Sensor, we worked with QHFZ to leverage their project’s amplifier RinA_p80α.
This year, QHFZ’s project is to develop a device that can be used to degrade uric acid. They used RinA_p80α in their project to improve the performance of the Sensor. In collaboration with QHFZ, we also tried to incorporate RinA_p80α into our project.
In our design, RinA_p80α was placed downstream of the Sensor, controlling the expression of GFP. By employing this strategy, we were able to elevate the fluorescence value significantly.
Figure 2: RinA_p80α Design（collabration with QHFZ）
However, we found that adding the amplifier also elevates the base value, so we developed a new amplifier, further optimizing the performance of the Sensor. Our new design was also recognized by QHFZ.
Figure 3: Advanced Amplifier Design
Collaboration Project 3:
cooperated with UCAS_China, using TEV-C1434 amplifier to improve the efficiency of Hg Sensor
While cooperating with QHFZ, we also cooperated with UCAS_China. In UCAS_China’s design, they applied TEV-C1434 to design a switch responsive to temperature. In this switch, controlled by a constitutive promoter, C1434, a transcriptional inhibitory protein, represses the expression of the output signal. However, since tevS, a recognition site for TEV protease, is inserted to C1434, TEV protease can cut and inactivate C1434, permitting the expression of the output signal. Besides, because TEV protease is a fairly sensitive protein, a limited amount of TEV protease can inactivate C1434. After communicating with UCAS_China, we considered this switch a potential amplifier, so we tried to employ it in our project.
We designed the following strategy. The basic design is similar to that of UCAS_China, but the expression of TEV is regulated by Hg ions. The results of the experiment showed that the fluorescence value is elevated significantly, which proved that the design of the amplifier was also effective.