Light-sensitive coupling of rhodopsin and melanopsin to Gi/o and Gq signal transduction in Caenorhabditis elegans

Activation of G-protein-coupled receptors (GPCRs) initiates signal transduction cascades that affect many physiological responses. The worm Caenorhabditis elegans expresses >1000 of these receptors along with their cognate heterotrimeric G proteins. Here, we report properties of 9-cis-retinal regenerated bovine opsin [(b)isoRho] and human melanopsin [(h)Mo], two light-activated, heterologously expressed GPCRs in the nervous system of C. elegans with various genetically engineered alterations. Profound transient photoactivation of G(i/o) signaling by (b)isoRho led to a sudden and transient loss of worm motility dependent on cyclic adenosine monophosphate, whereas transient photoactivation of G(q) signaling by (h)Mo enhanced worm locomotion dependent on phospholipase C beta. These transgenic C. elegans models provide a unique way to study the consequences of G(i/o) and G(q) signaling in vivo with temporal and spatial precision and, by analogy, their relationship to human neuromotor function.-Cao, P., Sun, W., Kramp, K., Zheng, M., Salom, D., Jastrzebska, B., Jin, H., Palczewski, K., Feng, Z. Light-sensitive coupling of rhodopsin and melanopsin to G(i/o) and G(q) signal transduction in Caenorhabditis elegans. FASEB J. 26, 480-491 (2012). www.fasebj.org