Adult Single-nucleus Neuronal Transcriptomes of Insulin Signaling Mutants Reveal Regulators of Behavior and Learning

Abstract

AbstractThe insulin/insulin-like signaling (IIS) pathway regulates many ofC. elegans’adult functions, including learning and memory1. While whole-worm and tissue-specific transcriptomic analyses have identified IIS targets2,3, a higher-resolution single-cell approach is required to identify changes that confer neuron-specific improvements in the long-lived insulin receptor mutant,daf-2. To understand how behaviors that are controlled by a small number of neurons change indaf-2mutants, we used the deep resolution of single-nucleus RNA sequencing to define each neuron type’s transcriptome in adult wild-type anddaf-2mutants. First, we found surprising differences between wild-type L4 larval neurons and young adult neurons in chemoreceptor expression, synaptic genes, and learning and memory genes. These Day 1 adult neuron transcriptomes allowed us to identify adult AWC-specific regulators of chemosensory function and to predict neuron-to-neuron peptide/receptor pairs. We then identified gene expression changes that correlate withdaf-2’simproved cognitive functions, particularly in the AWC sensory neuron that controls learning and associative memory4, and used behavioral assays to test their roles in cognitive function. Combining deep single-neuron transcriptomics, genetic manipulation, and behavioral analyses enabled us to identify genes that may function in a single adult neuron to control behavior, including conserved genes that function in learning and memory.One-Sentence SummarySingle-nucleus sequencing of adult wild-type anddaf-2 C. elegansneurons reveals functionally relevant transcriptional changes, including regulators of chemosensation, learning, and memory.