Difference between revisions of "Team:OUC-China/Project"

Background

Nowadays，quantitative has become a general trend, and of which the control of gene expression play a vital role. Until now, there’re several ways to control gene expression and consequently achieve stoichiometry and functional protein products.

Regulation of gene expression includes a wide range of mechanisms that are used by cells to increase or decrease the production of specific gene products(protein or RNA). Virtually any step of gene expression can be modulated, from transcriptional initiation, to RNA processing, and to the post-translational modification of a protein.

In eukaryotes, the modification of DNA’s chromatin structure, such as histone modifications directed by DNA methylation[1], ncRNA, or DNA-binding protein, may up or down regulate the expression of a gene.

This controls when transcription occurs and the amount of RNA be created. The mechanisms usually includes specificity factors, general transcription factors, repressors, activators, enhancers [2] and silencers.

In eukaryotes, there have some mechanisms on how much the mRNA is translated into proteins [4]. Cells do this by modulating the capping, splicing, addition of a Poly(A) Tail, the sequence-specific nuclear export rates, and, in several contexts, sequestration of the RNA transcript.

The translation of mRNA can also be controlled by a number of mechanisms[5], mostly at the level of initiation. The secondary structure of mRNA, antisense RNA binding, or protein binding[6] can all modulate the recruitment of the small ribosomal subunit.

So many regulation methods have developed to achieve gene expression on desired level. Accurate as they are, they can hardly control the relative expression of several cistrons simultaneously. They are usually performed on operon level and may not have difference influence on each cistron.

But on certain condition, it’s of vital importance to realize differential gene expression in polycistrons. For example, Team Imperial 2014 aimed to biosynthesize bacterial cellulose in E.coil, they need to transform two cistrons of different expression level into E.coil. Without efficient approaches, they did lots of jobs. They selected proper copied plasmid among 9 plasmids and then measured 15 Anderson promotors of different strength and finally selected a proper combination for the two different cistrons.

This year, OUC-iGEM team devoted to exploring a novel regulation method on post-transcriptional level to realize differential expression in a polycistron. Details see the design part.

Design

For the public, we tried to publicize synthetic biology using relatively easy language toward as many people as possible through our activities. We went to communities and tourist attractions and met people from the young to the old. With the help of our brochures, we explained basic knowledge of synthetic biology and explained the meaning of quantification in their daily lives. They then realized that basic necessities of life were closely linked to quantification, like dietary recipe. We also posted our video on website which used simple language and vivid flash to introduce what is synthetic biology and how it can make our life better.

Reference

Specific to people working on science and technology industry, we tried to promoting synthetic biology in a deeper way. Therefore, we held academic lectures in Qingdao Association for Science and Technology for a delegation from Tibet, China. Over 90 teachers participated in lectures and they had more knowledge about synthetic biology. Moreover, due to coming from Tibet where the economic and educational development is relatively backward, these teachers could bring the conception of synthetic biology to Tibet and promoted it in these remote regions.