Paulinella chromatophora
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA28047 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Paulinella chromatophora FK01 Genome sequencing
| PRJNA45921 | ENA
Project description:Genome- and transcriptome-analysis of the photosynthetic testate amoeba Paulinella micropora
| PRJDB3528 | ENA
Project description:5' end sequecing of Paulinella micropora's transcripts
| PRJDB4786 | ENA
Project description:The cercozoan amoeba Paulinella chromatophora contains photosynthetic organelles - termed chromatophores - that evolved from a cyanobacterium ~100 million years ago, independently from plastids in plants and algae. Despite its more recent origin, at least one third of the chromatophore proteome consists of nucleus-encoded proteins that are imported by an unknown mechanism across the chromatophore double envelope membranes. Chromatophore-targeted proteins fall into two classes. Proteins exceeding 250 amino acids carry a conserved N-terminal sequence extension, termed the ‘chromatophore transit peptide’ (crTP), that is presumably involved in guiding these proteins into the chromatophore. Short imported proteins do not carry discernable targeting signals. To explore whether the import of protein is accompanied by their N-terminal processing, here we used a mass spectrometry-based approach to determine protein N-termini in Paulinella chromatophora and identified N-termini of 208 chromatophore-localized proteins. Our study revealed extensive N-terminal modifications by acetylation and proteolytic processing in both, the nucleus and chromatophore-encoded fraction of the chromatophore proteome. Mature N-termini of 37 crTP-carrying proteins were identified, of which 30 were cleaved in a common processing region. Our results imply that the crTP mediates trafficking through the Golgi, is bipartite and surprisingly only the N-terminal third (‘part 1’) becomes cleaved upon import, whereas the rest (‘part 2’) remains at the mature proteins. In contrast, short imported proteins remain largely unprocessed. Finally, this work sheds light on N-terminal processing of proteins encoded in an evolutionary-early-stage photosynthetic organelle and suggests host-derived post-translationally acting factors involved in dynamic regulation of the chromatophore-encoded chromatophore proteome.
2023-04-06 | PXD028527 | Pride
Project description:Paulinella micropora strain:KR01 Genome sequencing and assembly
| PRJNA568118 | ENA
Project description:Paulinella chromatophora strain:CCAC0185 Transcriptome or Gene expression
| PRJNA311736 | ENA
Project description:The endosymbiotic acquisition of mitochondria and plastids >1 Ga ago profoundly impacted eukaryote evolution. Early stages of organelle integration however remain poorly understood. The amoeba Paulinella chromatophora contains more recently established cyanobacterium-derived photosynthetic organelles, termed “chromatophores”. To explore the re-arrangement of an organellar proteome during its integration into a eukaryotic host cell, we characterized the chromatophore proteome by mass spectrometry. Apparently, genetic control over the chromatophore has shifted substantially to the nucleus. Two classes of nuclear-encoded proteins are imported into the chromatophore, likely through independent pathways. Most imported proteins seem to derive from ancestral host genes rather than nuclear genes transferred from the endosymbiont. Intriguingly, the putative targeting signal found in one class of imported proteins confers chloroplast localization upon heterologous expression in a plant cell suggesting common features in chromatophore and plastid protein import pathways. Finally, combining experimental data with in silico predictions we provide a comprehensive catalogue of chromatophore-localized proteins.
2017-07-13 | PXD006531 | Pride