Optogenetic tool has broad prospects on synthetic biology, and the CcaS-CcaR system, which is developed from cyanobacteria has made obvious achievements, thus more and more teams are willing to use this system in their own projects. In the past two years, we have spent a great deal of time using it in our projects and accumulated a lot of experience (see more information in our previous wikis). This year, we collaborated with WHU-China and SDU-CHINA who use this system in project and sharing the experience how we regulated the expression of CcaS and CcaR protein to control this optogenetic tool and what we achieved.
We cooperated with the high school team, Worldshaper-Wuhan. We shared some information about our project and had several discussions then determined to have an experiment about the lncRNA IL7-AS in multiple cell lines. LncRNA IL7-AS is a newly discovered lncRNA, which might be a potential diagnostic biomarker and therapeutic target for renal cell carcinoma. Through this experiment, firstly, we want to know if the IL7-AS has tissue specificity to distinguish between cancer cells and healthy cells or not. Secondly, we want to explore its applicability for which this biomarker can be widely utilized to detect tumours. The Worldshaper-Wuhan team successfully demonstrated that IL7-AS has speciality and universality. There were significant expression differences among 293T (the healthy cell), 769-P (the adenocarcinoma cell) and 786-O (the adenocarcinoma cell) cell lines. The expression in 769-P and 786-O were higher than that of 293T, showing speciality and universality of IL7-AS. Through our team's suggestions and Worldshaper-Wuhan's experiment, their project improved and we also got a new biomarker and therapeutic target for future projects.
After the information we got from meetings and public investigation, we thought it’s necessary to enhance the targeting of engineered Salmonella we used, we designed a fuse protein which called OmpA-RGD to achieve this goal. RGD is a well-studied tumor homing tripeptide that specifically binds to alpha v beta 3 (αvβ3) integrin, which is widely overexpressed on cancer cells. So there’s a cell line called MDA-MB-231 surface displaying αvβ3 needed for our further targeting and safety experiments, with the great help of NAU-CHINA , we had channels to get this cell line from Shanghai Institute of Biochemistry and Cell Biology.
When we submitted our parts, we got the help of HUST-iGEM. HUST-iGEM helped us dry down our plasmid DNA in 96 well plate format, label our plate with our team name and submission number, and eventually send it by express. We are extremely grateful for their help.
We also took part in the iGEM EurAisan Meetup, where we shared our ideas and learned a lot. At the meeting, we had friendly communications with many iGEMers and gained a lot of advice during this meetup. They suggested more possible delivery vehicles to our project and a more logical poster design. We took part in a quiz competition and were award the prize for best collaboration quiz with our buddy team SFLS_Shenzhen. After the meetup, we're still talking on WeChat.
In August, we participated in the biggest iGEMer communication conference in China——Conference of China iGEMer Community (CCiC). During this meeting we communicated with teams tracking on therapy and reflected more about our project. For further collaboration,we met the captain of WHU-China and talked about the experience of our optogenetic tool.