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bioRxiv · 10.1101/2020.09.25.312835

First 3D-Structural Data of Full-length Rod-Outer-Segment Guanylyl Cyclase 1 in Bovine Retina by Cross-linking/Mass Spectrometry

Rehkamp, A.·Taenzler, D.·Tueting, C.·Kastritis, P. L.·Ihling, C. H.·Kipping, M.·Koch, K.-W.·Sinz, A.
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Abstract

The rod-outer-segment guanylyl cyclase 1 (ROS-GC1) is a key transmembrane protein for retinal phototransduction. Mutations of ROS-GC1 correlate with different retinal diseases that often lead to blindness. No structural data are available for ROS-GC1 so far. We performed a 3D-structural analysis of native ROS-GC1 from bovine retina by cross-linking/mass spectrometry (XL-MS) and computational modeling. Absolute quantification and activity measurements of native ROS-GC1 were performed by MS-based assays directly in bovine retina samples. Our data present the first 3D-structural analysis of active, full-length ROS-GC1 in bovine retina. We propose a novel domain organization for the intracellular domain ROS-GC1. Our XL-MS data reveal that the -helical domain connecting the kinase homology and catalytic domains can acquire different conformations. Also, the XL-MS data of native ROS-GC1 in bovine retina agree with a dimeric architecture. Our integrated approach can serve as a blueprint for conducting 3D-structural studies of membrane proteins in their native environment.

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Rehkamp, A., Taenzler, D., Tueting, C., Kastritis, P. L., Ihling, C. H., Kipping, M., Koch, K.-W., Sinz, A.. 2020-09-25. First 3D-Structural Data of Full-length Rod-Outer-Segment Guanylyl Cyclase 1 in Bovine Retina by Cross-linking/Mass Spectrometry. https://doi.org/10.1101/2020.09.25.312835

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