High-performance optical control of GPCR signaling by bistable animal opsins MosOpn3 and LamPP in a molecular property-dependent manner.

Optical control of G protein-coupled receptor (GPCR) signaling is a highly valuable approach for comprehensive understanding of GPCR-based physiologies and controlling them precisely. However, optogenetics for GPCR signaling is still developing and requires effective and versatile tools with performance evaluation from their molecular properties. Here, we systematically investigated performance of two bistable opsins that activate Gi/Go-type G protein (mosquito Opn3 (MosOpn3) and lamprey parapinopsin (LamPP)) in optical control in vivo using Caenorhabditis elegans. Transgenic worms expressing MosOpn3, which binds 13-cis retinal to form photopigments, in nociceptor neurons showed light-induced avoidance responses in the presence of all-trans retinal, a retinal isomer ubiquitously present in every tissue, like microbial rhodopsins and unlike canonical vertebrate opsins. Remarkably, transgenic worms expressing MosOpn3 were ~7,000 times more sensitive to light than transgenic worms expressing ChR2 in this light-induced behavior, demonstrating the advantage of MosOpn3 as a light switch. LamPP is a UV-sensitive bistable opsin having complete photoregenerative ability by green light. Accordingly, transgenic worms expressing LamPP in cholinergic motor neurons stopped moving upon violet light illumination and restored coordinate movement upon green light illumination, demonstrating color-dependent control of behavior using LamPP. Furthermore, we applied molecular engineering to produce MosOpn3-based tools enabling light-dependent upregulation of cAMP or Ca2+ levels and LamPP-based tool enabling clamping cAMP levels color dependently and context independently, extending their usability. These findings define the capacity of two bistable opsins with similar retinal requirement as ChR2, providing numerous strategies for optical control of various GPCR-based physiologies as well as GPCR signaling itself.

Phylogenetic relationships between the tideland snails Batillaria flectosiphonata in the Ryukyu Islands and B. multiformis in the Japanese Islands.

Phylogenetic relationships between two sibling species of Japanese tideland snails, namely, Batillaria multiformis from the Japanese Islands and B. flectosiphonata from the Ryukyu Islands, were analyzed on the basis of the nucleotide sequences of the mitochondrial gene for cytochrome oxidase I. Populations of B. multiformis were genetically distinct from those of B. flectosiphonata with the exception of a population from Amami-Oshima Island, which corresponded to the boundary between the distributions of these two species. Individuals with the mitochondrial gene of B. multiformis and those with the mitochondrial gene of B. flectosiphonata were collected from the same tidal flat on Amami-Oshima Island. All the snails with the mitochondrial gene of B. multiformis could be divided into two genetically distinct groups but there was no geographical structure to the distribution of these two groups. Individual populations of B. flectosiphonata in the Amami, Okinawa, Miyako and Yaeyama insular groups each consisted exclusively of a unique set of haplotypes, with the exception of a population at a northern site on Okinawajima Island, which included a few individuals with sequences related to those of individuals in the Amami insular group. All individuals from South Ryukyu formed a well-supported monophyletic group, while the monophyly of individuals from Central Ryukyu was not supported. The monophyly of B. multiformis was clearly demonstrated but there was no evidence to support that of B. flectosiphonata. Batillaria multiformis might have been derived from immigrants from the Ryukyu Islands, which became isolated and diverged genetically on the Japanese Islands.