Non-visual light modulates behavioral memory and gene expression in <i>Caenorhabditis elegans</i>.

Abstract

Visible light influences a range of physiological processes, yet how animals respond to it independently of the visual system remains largely unknown. Here, we uncover a previously undescribed light-induced transcriptional pathway that modulates behavioral plasticity in <i>Caenorhabditis elegans</i>, a roundworm without eyes. We demonstrate that ambient visible light or controlled-intensity visible-spectrum LED activates an effector gene <i>cyp-14A5</i> in non-neuronal tissues through the bZIP transcription factors ZIP-2 and CEBP-2. Light induction of <i>cyp-14A5</i> is more prominent at shorter wavelengths but is independent of the known blue light receptors LITE-1 and GUR-3 in <i>C. elegans</i>. This bZIP-dependent genetic pathway in non-neuronal tissues enhances behavioral adaptability and olfactory memory, suggesting a body-brain communication axis. Furthermore, we use the light-responsive <i>cyp-14A5</i> promoter to drive ectopic gene expression, causing synthetic light-induced sleep and rapid aging phenotypes in <i>C. elegans</i>. These findings advance our understanding of light-responsive mechanisms outside the visual system and offer a new genetic tool for visible light-inducible gene expression in non-neuronal tissues.