Plastid translocon recycling in dinoflagellates demonstrates the portability of complex plastids between hosts
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View abstract on PubMed
Summary
This summary is machine-generated.Marine algae gained complex plastids through multiple endosymbiotic events. This study shows Kareniaceae dinoflagellates acquired protein import machinery from haptophytes, facilitating plastid transfer and explaining their widespread distribution.
Area Of Science
- Eukaryotic cell biology
- Evolutionary biology
- Photosynthesis research
Background
- Primary plastids in land plants originate from cyanobacteria.
- Marine eukaryotes often possess complex plastids acquired via secondary endosymbiosis of other eukaryotes.
- The evolutionary history and mechanisms of complex plastid acquisition remain incompletely understood.
Purpose Of The Study
- To investigate the mechanism of protein import into complex plastids in Kareniaceae dinoflagellates.
- To determine if protein targeting machinery was transferred during secondary endosymbiosis.
- To assess the role of protein import in the horizontal transfer of plastids.
Main Methods
- Phylogenetic analysis of protein targeting components.
- Cryo-electron tomography to examine plastid structure.
- Comparative genomics of Kareniaceae and haptophyte lineages.
Main Results
- Kareniaceae dinoflagellates possess protein import machinery derived from haptophytes.
- No additional membranes were formed around the plastid during serial endosymbiosis in Kareniaceae.
- The haptophyte-derived import system appears sufficient for functional plastid integration.
Conclusions
- Complex red plastids are pre-adapted for horizontal gene transfer.
- Acquisition of host-compatible protein import systems facilitates plastid transmission.
- This mechanism likely contributes to the widespread distribution of complex plastids in diverse algal lineages.
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