Internships

Project title: Biomechanical approach of the locomotion of Drosophila larvae

RESEARCH TEAMS

Collective Animal Behavior (Centre de Recherches sur la Cognition Animale) & Team Crozatier/Vincent (Centre de Biologie du Développement)

Host institution: Centre de Biologie Intégrative (CBI) Website: http://cbi-toulouse.fr/fr/          

INFORMATION ON THE RESEARCH PROJECT

Project description:

          Our project aims at coupling a biomechanical approach (CRCA) and a genetic engineering approach (CBD to study the impact of genetic modifications of the muscle architecture on the locomotion of Drosphila larvae. Drosophila larvae move through a succession of muscular contraction waves, also called peristaltic, that propagate along their body longitudinal axis. The decoding of the genetic network involved in the identity of the dorso-lateral muscles of Drosophila larvae (Dubois et al, 2016) in the team Crozatier/Vincent (CBD) has allowed to generate viable mutant larvae in which a dorso-lateral muscle has been transformed in a dorsal muscle (Carayon et al, 2919). The use of imaging tools has further allowed to demonstrate that this transformation is sufficient to induce specific changes in the movement of the larvae. Our objective now is to analyze in details the effects of this transformation on the coordination of the muscular contraction within a larva body segment and on the propagation of the peristaltic wave on the successive segments of the larva body through the comparison of wild type flies and mutant flies. For this purpose we will use a system of high frequency macro videorecoding that has been specially designed in the CRCA for the 3D analysis of movement of walking insects and that has been recently adapted for the study of the locomotion of Drosophila larvae. Fluorescent markers will be used to visualize the muscles affected by the mutations. The coupling of imaging techniques and of a modelling approach will allow to better understand how the particular architecture of the dorsal, lateral and ventral muscles of the larvae allows to organize their peristaltic contractions and induce their movement.

References :
Dubois L, Frendo J-L, Chanut-Delalande H, Crozatier M and Vincent A. (2016). Genetic dissection of the Transcription Factor code controlling serial specification of muscle identities in Drosophila. Elife. 5. pii: e14979.

Carayon A, Bataillé L, Lebreton G, Dubois L, Pelletier A, Carrier Y,  Wystrach A, Vincent A and  Frendo J-L. (2019). Intrinsic control of muscle attachment sites matching doi: https://doi.org/10.1101/544569

Techniques that will be used by the student: 3D video recording, video analysis technique, 3D reconstruction, maintenance of Drosophila stocks

Required skills: data analysis techniques (R, Matlab)

Supervision:

Vincent FOURCASSIE, Jean-Louis FRENDO, Pierre MORETTO

E-mail: vincent.fourcassie@univ-tlse3.fr, jean-louis.frendo@univ-tlse3.fr, pierre.moretto@univ-tlse3.fr

Web page: http://cbi-toulouse.fr/fr/equipe-fourcassie, http://cbi-toulouse.fr/fr/equipe-vincent-crozatier

RESEARCH TEAM: Collective Animal Behavior (CRCA, Toulouse), Conception Bio-Inspirée (ISM, Marseille)

Description of the project:

Our project aims at appling a biomechanical approach (CRCA) to understand the efficiency of locomotion in Messor Barbarus who is known to carry heavy loads (10 times its own weight). For this purpose, we need to quantify the kinematic parameters to estimate the inertia characteristics and to determine the internal structure design (muscles and cuticle) of the ant’s body segments. We will assess the kinematics using a high frequency macro videorecoding that has been specially designed in the CRCA for the 3D analysis of gait in insect. The inertia characteristics will be estimated from dissection and modelization based on microscopic views and computed tomography of the different segments. This data will enable us to build a bio-inspired simulation of exoskeleton (CB-I).

Techniques that will be used by the student: 3D video recording, video analysis technique, 3D reconstruction, dissection.

Required skills: Dissection, data analysis techniques (Matlab), Model and simulation (Opensim)

SUPERVISION:
Pierre MORETTO, Isabelle MASSOU, Santiago ARROYAVE-TOBON.
E-mail: pierre.moretto@univ-tlse3.fr, isabelle.massou@univ-tlse3.fr, santiago.arroyave-tobon@univ-amu.fr