A Biosensor Memory Module: Cre Sensor

Analysis and imaging methods are an indispensable element of every scientific study - in a wider sense the results are only as good as their measurement methods are.

Photostimulation is one of the most important non-invasive analysis methods existing which allows researches to examine the relationship between metabolic processes, e.g. through activating a molecule via light treatment. What we want to do is to create a module in which we can do a snapshot of the activity of a sensor at any time.

We want to design a module, which is capable to make a ‘snapshot’ of sensor activity at any time, which in turn activates a promotor and changes gene expression. This snapshot is induced by a certain wavelength.

For caging we use Dronpa, a fluorescent protein. Dronpa is able to dimerise at 400nm and monomerises again at 500nm. Therefore it can be used reversibly for caging an enzyme. If a amino- and carboxy-terminus bound Dronpa dimerises, it will cover the active site of the enzyme and inactivates it this way. One can control this reversible mechanism by light.

To proof a successful activation of the enzyme a reporter is necessary. The Cre-recombinase suits well for this. Cre can be inserted into the DNA permanently as a sensor and is able to be controlled by light if bound to Dronpa. When activated, it can lead to the expression of an GFP gene construct, which is easily proofable due to its fluorescence.

This module can be used with a variety of associated enzymes and proteins to light-dependently controll these. The possible applications are plenty and the augur analytical and diagnostical value.

More information on http://2015.igem.org/Team:Tuebingen

Kevin Sabath, Nicolai von Kuegelgen, Jens Reich, Simon Huber, Nikolas Layer, Philipp Mayer, Adrian Geissler, Milena Krach, Stefanie Holz, Sarah Roffeis, Yvonne Thoma, Lisa Wellinger, Daniela Nguyen, Laura Schenkel, Katharina Sporbeck, Vivien Weber, Tim Kucera, Katerina Romanova, Viktor Beke