Overview

It is known that the length of anti-sense is related to its repression efficiency (N Nakashima et al., 2006^[1]), but the detail of relations between the length of anti-sense and their repression efficiency is still unclear. In this study, we made different lengths of anti-sense sequence (Fig. 1), and measured it's repression efficiencies.

Fig. 1 Each anti-sense repress mRNA.

Our experiments of anti-sense RNA (asRNA) sequence and it's length reveals the relation. Thus our findings will be a clue for other iGEMers that wants to design their own anti-sense sequence.

Introduction

In repressing gene by anti-sense, it is important to choose anti-sense length. However, it is difficult to decide anti-sense length. Even if they are too long, it doesn’t repress target RNA effectively. The reason is because RNA polymerase takes a lot of time to synthesize them, and the diffusion rate of them is also made to be low. However, too short asRNA also has some problem. The short anti-sense cannot bind to the specific part of mRNA because it has too short complementary sequences of target RNA. In the industrial and academic places, it is hoped to use anti-sense that has suitable repression efficiency. For example, you can create knock down recombinant organisms easily by using strong anti-sense, and in iGEM, you can make a bio-devices which has a complicated gene network and require fine-tuned gene expression. Gene’s expression is not only ON or OFF. As stated above, each cases need each repression efficiency. Researchers currently try to change anti-sense repression efficiency by changing anti-sense’s binding sequence. However, it is found that this method is difficult.

In this study, we made many kinds of anti-sense which have different lengths, and are investigated to have different repression efficiency. We wanted to create the diversity of repression efficiency by making many kinds of anti-sense length. We expect this results will help you decide anti-sense sequences. It is our satisfaction that our study tells scientists and iGEMers that repressing by anti-sense is easy and acurate.