Using c-kit to genetically target cerebellar molecular layer interneurons in adult mice

• Published in: PloS one 2017-06, Vol.12 (6), p.e0179347-e0179347
• Main Authors: Amat, Samantha B, Rowan, Matthew J M, Gaffield, Michael A, Bonnan, Audrey, Kikuchi, Chikako, Taniguchi, Hiroki, Christie, Jason M
• Format: Article
• Language: English
• Subjects: Action Potentials - physiology; Animals; Biology and Life Sciences; c-Kit protein; Cerebellar Cortex - cytology; Cerebellar Cortex - metabolism; Cerebellum; Cerebellum - cytology; Cerebellum - metabolism; Cloning; Cortex (motor); Cre recombinase; Fibers; Gene expression; Genetic engineering; In vitro methods and tests; Inhibition; Interneurons; Interneurons - cytology; Interneurons - metabolism; Kinases; Machinery; Machinery and equipment; Medicine and Health Sciences; Mice; Mice, Transgenic; Motor activity; Motor task performance; Neurosciences; Parallel fibers; Principal components analysis; Proto-Oncogene Proteins c-kit - genetics; Proto-Oncogene Proteins c-kit - metabolism; Purkinje cells; Recombinase; Research and Analysis Methods; Transcription
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0179347

The cerebellar system helps modulate and fine-tune motor action. Purkinje cells (PCs) provide the sole output of the cerebellar cortex, therefore, any cerebellar involvement in motor activity must be driven by changes in PC firing rates. Several different cell types influence PC activity including excitatory input from parallel fibers and inhibition from molecular layer interneurons (MLIs). Similar to PCs, MLI activity is driven by parallel fibers, therefore, MLIs provide feed-forward inhibition onto PCs. To aid in the experimental assessment of how molecular layer inhibition contributes to cerebellar function and motor behavior, we characterized a new knock-in mouse line with Cre recombinase expression under control of endogenous c-kit transcriptional machinery. Using these engineered c-Kit mice, we were able to obtain high levels of conditional MLI transduction in adult mice using Cre-dependent viral vectors without any PC or granule cell labeling. We then used the mouse line to target MLIs for activity perturbation in vitro using opto- and chemogenetics.