BIO472A - Modal de Biologie (2023-2024)

Experimentation is central to progress in biology. It enables working hypotheses to be tested. Thanks to cycles of hypothesis verification and refinement, we end up with predictive models, despite the great complexity of the objects studied: living beings.

We cannot guarantee that a student will be registered for a specific theme. The distribution of students is based on supply and demand. The following themes are likely to be opened:

- Bioluminescence:

The chemical energy extracted from organic molecules by living beings can be transformed into thermal energy, mechanical energy, electrical energy, and even light energy. This last property is more widespread than we think since it exists in several hundred species as diverse as bacteria, fungi and animals. We will study the green fluorescent protein (GFP) of the jellyfish Aequorea victoria. We will use the tools of genetic engineering, biochemistry and biophysics to understand the origin of this fluorescence and how to exploit it in various biotechnological fields. Firefly tail luciferin will also be discussed to understand the origin and mechanism of its bioluminescence.

-Antibodies: from immune defense to clinical diagnosis:

Antibodies, central molecules in the humoral immune response, play an essential role in the prevention of infections. Moreover, thanks to their precise characterization, they have also become essential tools for research, medical diagnosis and therapy, in particular anti-cancer. This Modal aims to characterize the biochemical properties of antibodies as well as to illustrate several examples of the use of antibodies in research and medical diagnosis. The use of a large number of classical techniques of biochemistry and biology also make this Modal an excellent introduction to laboratory work.

- Intracellular imaging:

The organization and dynamics of the cytoskeleton play an essential role in many eukaryotic cell life processes, such as migration, division or intracellular transport. The objective of this Modal is to observe the different components of the cytoskeleton (microtubule and actin filaments) inside human cells. It is an opportunity to introduce multiple techniques in cell biology (culture of human cells, immunocytochemistry, transfection), microscopy and digital modeling.

- Cloning:

This modal allows you to discover the key tools and techniques used daily in laboratories. Baker's yeast dihydrofolate reductase (DHFR) is an essential protein conserved in all eukaryotes. Thanks to its key role in cell growth and metabolism, DHFR is of pharmacological interest. It is the target of the few drugs that are used for the treatment of a wide spectrum of diseases. We will clone the gene coding for the eukaryotic DHFR in a bacterium, we will induce its expression and we will purify the protein produced. Finally, an enzymatic test will make it possible to functionally characterize the purified protein.

-Synthetic biology: design and construction of synthetic genetic oscillators:

Synthetic biology aims to design and build artificial life forms that perform a given function. Gene regulatory networks are sets of genes that interact with each other and with other molecules, via their expression products, allowing mutual control of their expression levels. One possible approach to synthetic biology is to modify existing genetic networks or design new ones, opening the way to the design of new biological functions. This is a very active area of ​​research with many potential applications. The purpose of this Modal is the study and fabrication of synthetic genetic oscillators, that is to say networks of unnatural genes with an oscillating behavior. It uses the following methods and techniques: modeling of gene networks, genetic engineering, cell culture, fluorescence microscopy, image analysis.