Download ARIEL LEVINE Postdoctoral Associate, The Salk Institute for

ARIEL LEVINE
Postdoctoral Associate, The Salk Institute for Biological Studies, La Jolla, CA, USA
EDUCATION/TRAINING
INSTITUTION AND LOCATION
Brandeis University, Waltham, MA
Rockefeller University, New York,
NY
Weill Medical College of Cornell
University, New York, NY
The Salk Institute for Biological
Studies, La Jolla, CA
DEGREE
YEAR
FIELD OF STUDY
B.S.
2000
Biology
PhD
2008
Developmental Biology
MD
2009
Medicine
Postdoc
2009 present
Neuroscience
Ariel Levine is an MD/PhD postdoctoral associate in the laboratory of Dr. Samuel
Pfaff at the Salk Institute, studying how the central nervous system controls
movement. In particular, I am working to uncover how the neurons of the spinal cord
receive motor commands from the brain and sensory systems and integrate these
into functional motor outputs. Building on the expertise of the Pfaff lab and
developing new strategies, I approach this question with a variety of techniques,
including cutting-edge viral tracing techniques, neuronal and synaptic labeling,
optogenetics, large-scale gene expression database analysis, knock-in mouse
genetics, and behavioral testing. Most recently, I identified a molecularly-defined
population of neurons in the medial deep dorsal horn of the spinal cord that receive
direct inputs from the motor cortex and sensory pathways, and whose activation is
sufficient to drive coordinated multi-joint motor activity. Ongoing research is focused
on examining the strategy by which these neurons ‘encode’ for movements, how they
learn to code for new movements, and the role of these neurons during behavior and
following injury.
Identification of a Cellular Node for Motor Control Pathways
Ariel J. Levine; Christopher A. Hinckley; Kathryn L. Hilde, Shawn P. Driscoll, Samuel
L. Pfaff
The rich behavioral repertoire of animals is encoded within the central nervous
system as a set of motorneuron activation patterns. However, the neurons that
orchestrate motor programs, as well as their cellular properties and connectivity are
poorly understood. We have identified a population of premotor spinal neurons that
may provide the cellular basis for encoding coordinated motor output programs.
These molecularly-defined “motor synergy encoder” (MSE) neurons represent a
central node in neural pathways for volitional and reflexive movement. Direct optical
stimulation of MSE neurons is sufficient to drive reliable patterns of activity in multiple
motor groups, and we found that the evoked motor patterns vary based on the rostrocaudal location of the stimulated MSE. Thus, the spatial organization of MSE neurons
may simplify the computational challenge of coordinating muscle group activity by
employing a circuit structure that translates MSE neuron position into specific motor
programs. In clinical cases of spinal cord injury and upper motor neuron
degeneration, spinal neuronal networks are effectively isolated from descending input
and voluntary movement of the body is compromised. We propose that it may be
useful to directly activate MSE cells to facilitate controlled movement in patients.