RP18

Linking the Intestinal Microbiota and Energy Metabolism: A Functional Metagenomic Approach

For this research project, Mr Tomas DE WOUTERS has been recruited.

Main supervisor

Hervé M. BLOTTIERE  (INRA Jouy en Josas,  UMR 1319 Micalis)

Co-supervisor

Joël DORE (INRA Jouy en Josas,  UMR 1319 Micalis)

Duration: 36 months; This research project is funded  by ANR and is part of the MicroObes project

Start date: March 2008 to March 2011

Objective

The presented PhD project aims to study the molecular mechanisms regulating the intestinal microbiota’s impact on energy harvest and metabolism of its host.

Approach

Our main target consists in the lipoprotein lipase (LPL) inhibiting protein ANGPTL4/FIAF (Angiopoietin-like Protein4/ Fasting-Induced Adipose Factor), an angiopoietin-like protein which could be the linking factor between the microbiota and the regulation of fat storage by the host. To study the microbiota’s impact on the regulation of ANGPTL4 expression, the functional metagenomic approach was chosen. In order to find bacterial clones modulating the expression of our target gene, two metagenomic libraries (one lean and one obese subject) will be screened on stably tranfected cell lines (Caco2 and HT29).Therefore we constructed a plasmid containing the luciferase reporter gene under FIAF promoter control. The most responding bacterial clones will be selected for further mechanistic studies including the identification of the bacterial gene involved.

Deliverables

After analysing the promoter region a reporter system on the control of the ANGPTL4 promoter has to be designed and constructed.

With the obtained constructs, ANGPTL4 reporter cell lines have to be established in different intestinal epithelial cell lines and validated.

High throughput screening of metagenomic libraries will be performed and after adequate analysis, the most interesting clones will be further analysed on a molecular and functional level.