Chloroplast ribosomes interact with the insertase Alb3 in the thylakoid membrane
- Members of the Oxa1/YidC/Alb\(_3\) protein family are involved in the insertion, folding, and assembly of membrane proteins in mitochondria, bacteria, and chloroplasts. The thylakoid membrane protein Alb\(_3\) mediates the chloroplast signal recognition particle (cpSRP)-dependent posttranslational insertion of nuclear-encoded light harvesting chlorophyll a/b-binding proteins and participates in the biogenesis of plastid-encoded subunits of the photosynthetic complexes. These subunits are cotranslationally inserted into the thylakoid membrane, yet very little is known about the molecular mechanisms underlying docking of the ribosome-nascent chain complexes to the chloroplast SecY/Alb\(_3\) insertion machinery. Here, we show that nanodisc-embedded Alb\(_3\) interacts with ribosomes, while the homolog Alb\(_4\), also located in the thylakoid membrane, shows no ribosome binding. Alb\(_3\) contacts the ribosome with its C-terminal region and at least one additional binding site within its hydrophobic core region. Within the C-terminal region, two conserved motifs (motifs III and IV) are cooperatively required to enable the ribosome contact. Furthermore, our data suggest that the negatively charged C-terminus of the ribosomal subunit uL\(_{4c}\) is involved in Alb\(_3\) binding. Phylogenetic analyses of uL\(_4\) demonstrate that this region newly evolved in the green lineage during the transition from aquatic to terrestrial life.
Author: | Bernd AckermannGND, Beatrix DünschedeGND, Björn PietzenukGND, Bo Højen JustesenGND, Ute KrämerORCiDGND, Eckhard HofmannORCiDGND, Thomas Günther-PomorskiORCiDGND, Danja SchünemannGND |
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URN: | urn:nbn:de:hbz:294-87628 |
DOI: | https://doi.org/10.3389/fpls.2021.781857 |
Parent Title (English): | Frontiers in plant science |
Publisher: | Frontiers Media |
Place of publication: | Lausanne |
Document Type: | Article |
Language: | English |
Date of Publication (online): | 2022/03/24 |
Date of first Publication: | 2021/12/23 |
Publishing Institution: | Ruhr-Universität Bochum, Universitätsbibliothek |
Tag: | Open Access Fonds Oxa1/YidC/Alb3 protein family; cotranslational protein transport; nanodiscs; ribosomes; thylakoid membrane biogenesis |
Volume: | 12 |
Issue: | Article 781857 |
First Page: | 781857-1 |
Last Page: | 781857-13 |
Note: | Article Processing Charge funded by the Open Access Publication Fund of Ruhr-Universität Bochum. |
Institutes/Facilities: | Lehrstuhl für Pflanzenphysiologie, Arbeitsgruppe Molekularbiologie pflanzlicher Organellen |
Lehrstuhl für Pflanzenphysiologie | |
Fakultät für Biologie und Biotechnologie, Arbeitsgruppe Molekularbiologie pflanzlicher Organellen | |
Dewey Decimal Classification: | Naturwissenschaften und Mathematik / Biowissenschaften, Biologie, Biochemie |
open_access (DINI-Set): | open_access |
faculties: | Fakultät für Biologie und Biotechnologie |
Licence (English): | Creative Commons - CC BY 4.0 - Attribution 4.0 International |