Expression of thioredoxin-1 in the ASJ neuron corresponds with and enhances intrinsic regenerative capacity under lesion conditioning in C. elegans

Abstract

AbstractA conditioning lesion of the peripheral sensory axon triggers robust central axon regeneration in mammals. We visualize the ASJ neuron of C. elegans with a cell-specific green fluorescent protein reporter driven by a thioredoxin trx-1 promoter and trigger conditioned regeneration by laser surgery or genetic disruption of sensory pathways. Utilizing calibrated fluorescent beads, we demonstrate that these neurons brighten when conditioned, suggesting that trx-1 expression indicates regenerative capacity. We show that trx-1 functionally enhances conditioned regeneration but inhibits non-conditioned regeneration. Finally, six strains isolated in a forward genetic screen for reduced fluorescence also show reduced axon outgrowth. We demonstrate a link between trx-1 expression and the conditioned state that we leverage to rapidly assess regenerative capacity.