Previous work has demonstrated that fusion of a luciferase to an opsin, to create a luminescent opsin or luminopsin, provides a genetically encoded means of manipulating neuronal activity via both chemogenetic and optogenetic approaches. Here we have expanded and refined the versatility of luminopsin tools by fusing an alternative luciferase variant with high light emission, Gaussia luciferase mutant GLucM23, to depolarizing and hyperpolarizing channelrhodopsins with increased light sensitivity. The combination of GLucM23 with Volvox channelrhodopsin-1 produced LMO4, while combining GLucM23 with the anion channelrhodopsin iChloC yielded iLMO4. We found efficient activation of these channelrhodopsins in the presence of the luciferase substrate, as indicated by responses measured in both single neurons and in neuronal populations of mice and rats, as well as by changes in male rat behavior during amphetamine-induced rotations. We conclude that these new luminopsins will be useful for bimodal opto- and chemogenetic analyses of brain function.

The need to develop efficient therapies for neurodegenerative diseases is urgent, especially given the increasing percentages of the population living longer, with increasing chances of being afflicted with conditions like Parkinson's disease (PD). A promising curative approach toward PD and other neurodegenerative diseases is the transplantation of stem cells to halt and potentially reverse neuronal degeneration. However, stem cell therapy does not consistently lead to improvement for patients. Using remote stimulation to optogenetically activate transplanted cells, we attempted to improve behavioral outcomes of stem cell transplantation. We generated a neuronal precursor cell line expressing luminopsin 3 (LMO3), a luciferase-channelrhodopsin fusion protein, which responds to the luciferase substrate coelenterazine (CTZ) with emission of blue light that in turn activates the opsin. Neuronal precursor cells were injected bilaterally into the striatum of homozygous aphakia mice, which carry a spontaneous mutation leading to lack of dopaminergic neurons and symptoms of PD. Following transplantation, the cells were stimulated over a period of 10 days by intraventricular injections of CTZ. Mice receiving CTZ demonstrated significantly improved motor skills in a rotarod test compared to mice receiving vehicle. Thus, bioluminescent optogenetic stimulation of transplanted neuronal precursor cells shows promising effects in improving locomotor behavior in the aphakia PD mouse model and encourages further studies to elucidate the mechanisms and long-term outcomes of these beneficial effects.

BackgroundMillions of Americans have tested positive for COVID-19. The illness has a range of clinical symptoms with varying degrees of symptom severity; there is limited research about the lived experience of having COVID-19.ObjectiveThe study aim was to understand the lived experience of having COVID-19, provide detail on the length and severity of symptoms as well as coping mechanisms of those with the illness, and identify issues individuals face when accessing healthcare.MethodsThis phenomenological qualitative study included semistructured interviews of 45 people ages 18 years and older living in the United States who tested positive for COVID-19. Inductive content analysis was employed for subjective interpretation of the text through a systematic coding classification to identify themes for analysis and conclusions.ResultsThis study details a variety of symptom presentations of individuals who tested positive for COVID-19 as well as mental health concerns related to fear and living with COVID-19.DiscussionIndividuals expressed varying emotions when finding they tested positive for COVID-19. Many conveyed fear of having COVID-19 and indicated it was a traumatic experience. This fear is an important clinical finding that policymakers and providers should consider when treating acute and chronic COVID-19 patients. Finally, many participants, commonly referred to as “long haulers,” experienced ongoing and lingering symptoms highlighting an area in need of further research.