Gloeobacter and human chimeric rhodopsin (GHCR) (GHCR)

Gloeobacter and human chimeric rhodopsin (GHCR) is an engineered optogenetic receptor designed for vision restoration in patients with inherited retinal degenerations, such as retinitis pigmentosa [1][15]. It is a hybrid protein consisting of the microbial rhodopsin from Gloeobacter violaceus fused with the cytoplasmic loops of human rhodopsin [1][4]. This design combines the high light sensitivity and G-protein coupling efficiency of mammalian opsins with the stability and non-bleaching properties of microbial opsins [1][5]. When expressed in surviving retinal interneurons (e.g., bipolar or ganglion cells) via gene therapy, GHCR acts as a light-activated switch that triggers intracellular signaling cascades, effectively turning these cells into new photoreceptors [1][15]. This approach is "gene-agnostic," meaning it can potentially treat various forms of retinal blindness regardless of the underlying genetic mutation [3][15]. Clinical development is currently led by Restore Vision Inc. with their lead candidate RV-001, which recently entered Phase I/II clinical trials [15].

Other names

Chimeric rhodopsinGloeobacter-human chimeric rhodopsincoGHCRRV-001Opto-GPCR

The chimeric rhodopsin acts as an optogenetic actuator that, upon absorption of light, undergoes a conformational change to activate intracellular G-protein signaling pathways (such as Gi/o), thereby converting non-photoreceptive retinal neurons into functional light sensors to bypass degenerated photoreceptors [1][15].