Structural basis for cpSRP43 chromodomain selectivity and dynamics in Alb3 insertase interaction
Canonical membrane protein biogenesis requires co-translational delivery of ribosome-associated proteins to the Sec translocase and depends on the signal recognition particle (SRP) and its receptor (SR). In contrast, high-throughput delivery of abundant light-harvesting chlorophyll a,b-binding prote...
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| Main Authors: | , , , , , , |
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| Format: | Article (Journal) |
| Language: | English |
| Published: |
16 Nov 2015
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| In: |
Nature Communications
Year: 2015, Volume: 6 |
| ISSN: | 2041-1723 |
| DOI: | 10.1038/ncomms9875 |
| Online Access: | Verlag, lizenzpflichtig, Volltext: https://doi.org/10.1038/ncomms9875 Verlag, lizenzpflichtig, Volltext: https://www.nature.com/articles/ncomms9875 
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| Author Notes: | Annemarie Horn, Janosch Hennig, Yasar L. Ahmed, Gunter Stier, Klemens Wild, Michael Sattler, Irmgard Sinning |
| Summary: | Canonical membrane protein biogenesis requires co-translational delivery of ribosome-associated proteins to the Sec translocase and depends on the signal recognition particle (SRP) and its receptor (SR). In contrast, high-throughput delivery of abundant light-harvesting chlorophyll a,b-binding proteins (LHCPs) in chloroplasts to the Alb3 insertase occurs post-translationally via a soluble transit complex including the cpSRP43/cpSRP54 heterodimer (cpSRP). Here we describe the molecular mechanisms of tethering cpSRP to the Alb3 insertase by specific interaction of cpSRP43 chromodomain 3 with a linear motif in the Alb3 C-terminal tail. Combining NMR spectroscopy, X-ray crystallography and biochemical analyses, we dissect the structural basis for selectivity of chromodomains 2 and 3 for their respective ligands cpSRP54 and Alb3, respectively. Negative cooperativity in ligand binding can be explained by dynamics in the chromodomain interface. Our study provides a model for membrane recruitment of the transit complex and may serve as a prototype for a functional gain by the tandem arrangement of chromodomains. |
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| Item Description: | Gesehen am 14.09.2020 |
| Physical Description: | Online Resource |
| ISSN: | 2041-1723 |
| DOI: | 10.1038/ncomms9875 |