Triadic!

Light is very common in our daily life, but using light as the signal to regulate gene expression is a new concept. Recently, more and more researchers choose light as an experimental regulatory factor. Due to its easy-to-control process and accurately adjustable characteristics, light attracts more and more biologists as an emerging experiment tool.

There are numerous light controlled gene expression systems, and each of them has its feature and the most suitable occasion to use. Relatively, there are less light controlled systems that allow people to use 2 or more lights simultaneously and independently. This year we intend to use light to regulate gene expressions on genomic level, so if we can find 3 light controlled systems that can work together and not interfere with each other, our goal will be easier to realize.

After lots of paper-reading work and discussion, we finally select red, green, and blue light gene regulated systems. These 3 systems involve 3 light colors, every 2 of which have small overlapping range of wavelength. With help of professors majoring in physics and electronic engineering, we calculate the light intensity needed and did some hardware design and testing work.The energy distribution versus wavelength under different currents of three lights is shown below. And three vertical lines with different colors mean the excitation wavelength of different light sensing proteins.

From this figure we can see that there is no overlap between red and green light and there is a little overlapping area between green and blue light. However, if we take the excitation wavelength of green and blue light sensing proteins into consideration, we can find that the overlapping area will not affect the performance of our system.

Looking around, we live in such a colorful world. All of these brilliant colors are formed by three primary colors. In our project, we also wish to use red, green, and blue light to weave a shining picture, a blueprint showing a bright future of the new application of our project.