@article {64814, title = {Chronology-based architecture of descending circuits that underlie the development of locomotor repertoire after birth.}, journal = {eLife}, volume = {8}, year = {2019}, month = {2019 Feb 25}, abstract = {

The emergence of new and increasingly sophisticated behaviors after birth is accompanied by dramatic increase of newly established synaptic connections in the nervous system. Little is known, however, of how nascent connections are organized to support such new behaviors alongside existing ones. To understand this, in the larval zebrafish we examined the development of spinal pathways from hindbrain V2a neurons and the role of these pathways in the development of locomotion. We found that new projections are continually layered laterally to existing neuropil, and give rise to distinct pathways that function in parallel to existing pathways. Across these chronologically layered pathways, the connectivity patterns and biophysical properties vary systematically to support a behavioral repertoire with a wide range of kinematics and dynamics. Such layering of new parallel circuits equipped with systematically changing properties may be central to the postnatal diversification and increasing sophistication of an animal{\textquoteright}s behavioral repertoire.

}, issn = {2050-084X}, doi = {10.7554/eLife.42135}, author = {Pujala, Avinash and Koyama, Minoru} } @article {65379, title = {CLADES: a programmable sequence of reporters for lineage analysis}, journal = {bioRxiv}, year = {2019}, month = {2019 May 30}, abstract = {

We present CLADES (Cell Lineage Access Driven by an Edition Sequence), a technology for cell lineage studies based on CRISPR/Cas9. CLADES relies on a system of genetic switches to activate and inactivate reporter genes in a pre-determined order. Targeting CLADES to progenitor cells allows the progeny to inherit a sequential cascade of reporters, coupling birth order with reporter expression. This gives us temporal resolution of lineage development that can be used to deconstruct an extended cell lineage by tracking the reporters expressed in the progeny. When targeted to the germ line, the same cascade progresses across animal generations, marking each generation with the corresponding combination of reporters. CLADES thus offers an innovative strategy for making programmable cascades of genes that can be used for genetic manipulation or to record serial biological events.

}, doi = {https://doi.org/10.1101/655308}, author = {Garcia-Marques, Jorge and Yang, Ching-Po and Isabel Espinosa Medina and Koyama, Minoru and Lee, Tzumin} } @article {65008, title = {A circuit motif in the zebrafish hindbrain for a two alternative behavioral choice to turn left or right.}, journal = {Elife}, volume = {5}, year = {2016}, month = {2016 08 09}, abstract = {

Animals collect sensory information from the world and make adaptive choices about how to respond to it. Here, we reveal a network motif in the brain for one of the most fundamental behavioral choices made by bilaterally symmetric animals: whether to respond to a sensory stimulus by moving to the left or to the right. We define network connectivity in the hindbrain important for the lateralized escape behavior of zebrafish and then test the role of neurons by using laser ablations and behavioral studies. Key inhibitory neurons in the circuit lie in a column of morphologically similar cells that is one of a series of such columns that form a developmental and functional ground plan for building hindbrain networks. Repetition within the columns of the network motif we defined may therefore lie at the foundation of other lateralized behavioral choices.

}, keywords = {Action Potentials, Animals, Animals, Genetically Modified, Behavior, Animal, Choice Behavior, Laser Therapy, Locomotion, Neural Pathways, Neurons, Patch-Clamp Techniques, Perception, Rhombencephalon, Zebrafish}, issn = {2050-084X}, doi = {10.7554/eLife.16808}, author = {Koyama, Minoru and Minale, Francesca and Shum, Jennifer and Nishimura, Nozomi and Schaffer, Chris B and Fetcho, Joseph R} }