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Mapping signal transduction in bistable jumping spider rhodopsin 1
Flavio Costa1, Emanuele Telari2, Daniel Moreno-Rodríguez1
1Dipartimento di Ingegneria Meccanica e Aerospaziale, Sapienza Università di Roma, Rome, Italy.
Biophysical Journal
|November 5, 2025
Summary
Researchers studied jumping spider rhodopsin 1 (JSR1) activation. Microsecond simulations revealed Trp290 is key for transmitting signals from retinal to the G-protein site, advancing optogenetics.
Area of Science:
- Biochemistry
- Molecular Biology
- Biophysics
Background:
- G-protein-coupled receptors (GPCRs) are vital for cellular signaling and major drug targets.
- Bistable rhodopsins, like jumping spider rhodopsin 1 (JSR1), show potential for optogenetics but their activation mechanisms are unclear.
Purpose of the Study:
- Investigate allosteric communication pathways in JSR1.
- Elucidate the role of retinal configuration in JSR1 activation.
- Understand JSR1's signal transduction for optogenetic applications.
Main Methods:
- Microsecond equilibrium molecular dynamics simulations.
- Network analysis and machine learning.
- Analysis of JSR1 structural states with different retinal isomers (9-cis, 11-cis, all-trans).
Main Results:
- Identified Trp290 as a critical residue for signal transmission from the retinal chromophore to the G-protein binding site.
- Found that residues along the TM6 helix also play a role in JSR1 activation.
- Characterized structural differences across functional states influenced by retinal isomerization.
Conclusions:
- Trp290 is essential for transmitting light-induced retinal movements during JSR1 activation.
- These findings enhance understanding of bistable rhodopsin mechanisms.
- The study supports the potential of JSR1 in developing novel light-driven technologies.
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