Motor Neuron Development And Circuitry In The Adult Leg

          Adult fruit flies walk using six legs that move in a highly coordinated and stereotyped manner. The motor neurons that command these movements are located in the central nervous system (CNS) and send axons to the legs that synapse onto specific muscles. We are characterizing the molecular signatures that give each of these motor neurons their specific identities, focusing on the lineages that they are derived from and the transcription factors they express. In addition, we are developing assays that allow us to monitor fly walking at high resolution, with the goal of carrying out genetic screens to find genes and neurons that are required for motor coordination in the adult.

Current lab members working on this project: Cesar Mendes, Jonathan Enriquez, Lalanti Venkatasubramanian, Clare Howard, Meredith Peterson, Laura Quintana Rio, Matt Eveland

Recent papers:

Kinematic responses to changes in walking orientation and gravitational load in Drosophila melanogaster. Mendes CS, Rajendren SV, Bartos I, Márka S, Mann RS. PloS one. 2014; 9(10):e109204. PMID: 25350743 PMCID: PMC4211655

Neuroscience. The Michael Jackson fly. Mann RS. Science (New York, N.Y.). 2014; 344(6179):48-9.  PMID: 24700848 PMCID: PMC4143233

Swept confocally-aligned planar excitation (SCAPE) microscopy for high speed volumetric imaging of behaving organisms. Bouchard MB, Voleti V, Mendes CS, Lacefield C, Grueber WB, et al. Nature photonics. 2015; 9(2):113-119. PMID: 25663846 PMCID: PMC4317333

Specification of individual adult motor neuron morphologies by combinatorial transcription factor codes. Enriquez J, Venkatasubramanian L, Baek M, Peterson M, Aghayeva U, et al. Neuron. 2015; 86(4):955-70. PMID: 25959734 PMCID: PMC4441546


____________________________________________________________

Get the Flash Player to see this content.

High speed video slowed down to reveal the walking pattern of a fruit fly. Flies walk most typically using the so-called tripod gait, where three legs are in stance phase (touching the surface) and three legs are in swing phase (swinging forward) at any one time.

Using our new method based on frustrated Total Internal Reflection (fTIR) we now visualize and quantify footsteps as shown in the video WT_fly_processed. See Mendes et al. for details.

 ____________________________________________________________

Figure 8 Neuron revision

 

Combinatorial control of adult motor neuron development. See Enriquez et al for details.

 ____________________________________________________________

A single coxa motor neuron cell body and its dendrites is labeled in the adult CNS by a MARCM experiment. See Baek and Mann 2009 and Enriquez et al 2015 for details.

  ____________________________________________________________

A single coxa motor neuron axon synapsing onto a muscle in the adult leg. 

  ____________________________________________________________

The sensory and motor neuron circuitry relevant to adult walking in the fruit fly.

 ____________________________________________________________

Representative publications:

Baek M, Mann RS. Lineage and birth date specify motor neuron targeting and dendritic architecture in adult Drosophila. J Neurosci. (2009) May 27;29(21):6904-16.

PDF: Baek and Mann JNeuro

César S Mendes, Imre Bartos, Turgay Akay, Szabolcs Márka, Richard S Mann. Quantification of gait parameters in freely walking wild type and sensory deprived Drosophila melanogaster. eLife 2013 10.7554/eLife.00231

The Laboratory of Richard S Mann
Department of Biochemistry and Molecular Biophysics
Columbia University Medical Center
701 West 168th Street, HHSC 1104
New York, NY 10032
212.305.2111

Also visit us on
Website By: actionapple.com