Rhodopsin-bestrophin fusion proteins from unicellular algae form gigantic pentameric ion channels

Citation:

A. Rozenberg, Kaczmarczyk, I. , Matzov, D. , Vierock, J. , Nagata, T. , Sugiura, M. , Katayama, K. , Kawasaki, Y. , Konno, M. , Nagasaka, Y. , Aoyama, M. , Das, I. , Pahima, E. , Church, J. , Adam, S. , Borin, V.A. , Chazan, A. , Augustin, S. , Wietek, J. , Dine, J. , Peleg, Y. , Kawanabe, A. , Fujiwara, Y. , Yizhar, O. , Sheves, M. , Schapiro, I. , Furutani, Y. , Kandori, H. , Inoue, K. , Hegemann, P. , Béjà, O. , and Shalev-Benami, M. . 2022. “Rhodopsin-Bestrophin Fusion Proteins From Unicellular Algae Form Gigantic Pentameric Ion Channels”. Nature Structural And Molecular Biology, 29, Pp. 592 - 603. https://www.scopus.com/inward/record.uri?eid=2-s2.0-85132206207&doi=10.1038%2fs41594-022-00783-x&partnerID=40&md5=7b9998167b0641662705b948ee69156d.

Abstract:

Many organisms sense light using rhodopsins, photoreceptive proteins containing a retinal chromophore. Here we report the discovery, structure and biophysical characterization of bestrhodopsins, a microbial rhodopsin subfamily from marine unicellular algae, in which one rhodopsin domain of eight transmembrane helices or, more often, two such domains in tandem, are C-terminally fused to a bestrophin channel. Cryo-EM analysis of a rhodopsin-rhodopsin-bestrophin fusion revealed that it forms a pentameric megacomplex ( 700 kDa) with five rhodopsin pseudodimers surrounding the channel in the center. Bestrhodopsins are metastable and undergo photoconversion between red- and green-absorbing or green- and UVA-absorbing forms in the different variants. The retinal chromophore, in a unique binding pocket, photoisomerizes from all-trans to 11-cis form. Heterologously expressed bestrhodopsin behaves as a light-modulated anion channel. © 2022, The Author(s), under exclusive licence to Springer Nature America, Inc.

Notes:

Export Date: 06 April 2024; Cited By: 18