Analysis of the SNARE Stx8 recycling reveals that the retromer-sorting motif has undergone evolutionary divergence
| Autor: | Francisco Yanguas, María Henar Valdivieso |
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| Přispěvatelé: | Ministerio de Ciencia, Innovación y Universidades (España), Agencia Estatal de Investigación (España), European Commission, Junta de Castilla y León |
| Rok vydání: | 2021 |
| Předmět: |
Cancer Research
Retromer Amino Acid Motifs Vesicular Transport Proteins Yeast and Fungal Models QH426-470 Salt Stress Mechanical Treatment of Specimens Biochemistry Schizosaccharomyces Pombe VPS35 Database and Informatics Methods Syntaxin Amino Acids Genetics (clinical) Alanine biology Organic Compounds Eukaryota Salt Tolerance Alanine scanning Cell biology Protein Transport Chemistry Experimental Organism Systems Specimen Disruption Physical Sciences Saccharomyces Cerevisiae Cellular Structures and Organelles SNARE Proteins Sequence Analysis Schizosaccharomyces Protein Binding Research Article endocrine system Endosome Bioinformatics Sorting Nexins Endosomes Vesicle Fusion Research and Analysis Methods Evolution Molecular Fungal Proteins Saccharomyces Model Organisms Sequence Motif Analysis Genetics Humans Protein Interaction Domains and Motifs Amino Acid Sequence Vesicles Molecular Biology Ecology Evolution Behavior and Systematics Organic Chemistry Organisms Fungi Chemical Compounds Biology and Life Sciences Proteins Cell Biology biology.organism_classification Yeast Aliphatic Amino Acids Specimen Preparation and Treatment Schizosaccharomyces pombe Vacuoles Animal Studies |
| Zdroj: | Digital.CSIC. Repositorio Institucional del CSIC instname PLoS Genetics PLoS Genetics, Vol 17, Iss 3, p e1009463 (2021) |
| Popis: | Fsv1/Stx8 is a Schizosaccharomyces pombe protein similar to mammalian syntaxin 8. stx8Δ cells are sensitive to salts, and the prevacuolar endosome (PVE) is altered in stx8Δ cells. These defects depend on the SNARE domain, data that confirm the conserved function of syntaxin8 and Stx8 in vesicle fusion at the PVE. Stx8 localizes at the trans-Golgi network (TGN) and the prevacuolar endosome (PVE), and its recycling depends on the retromer component Vps35, and on the sorting nexins Vps5, Vps17, and Snx3. Several experimental approaches demonstrate that Stx8 is a cargo of the Snx3-retromer. Using extensive truncation and alanine scanning mutagenesis, we identified the Stx8 sorting signal. This signal is an IEMeaM sequence that is located in an unstructured protein region, must be distant from the transmembrane (TM) helix, and where the 133I, 134E, 135M, and 138M residues are all essential for recycling. This sorting motif is different from those described for most retromer cargoes, which include aromatic residues, and resembles the sorting motif of mammalian polycystin-2 (PC2). Comparison of Stx8 and PC2 motifs leads to an IEMxx(I/M) consensus. Computer-assisted screening for this and for a loose Ψ(E/D)ΨXXΨ motif (where Ψ is a hydrophobic residue with large aliphatic chain) shows that syntaxin 8 and PC2 homologues from other organisms bear variation of this motif. The phylogeny of the Stx8 sorting motifs from the Schizosaccharomyces species shows that their divergence is similar to that of the genus, showing that they have undergone evolutionary divergence. A preliminary analysis of the motifs in syntaxin 8 and PC2 sequences from various organisms suggests that they might have also undergone evolutionary divergence, what suggests that the presence of almost-identical motifs in Stx8 and PC2 might be a case of convergent evolution. Author summary Eukaryotes possess membranous intracellular compartments, whose communication is essential for cellular homeostasis. Protein complexes that facilitate the generation, transport, and fusion of coated vesicles mediate this communication. Since alterations in these processes lead to human disease, their characterization is of biological and medical interest. Retromer is a protein complex that facilitates retrograde trafficking from the prevacuolar endosome to the Golgi, being essential for the functionality of the endolysosomal system. SNAREs are required for vesicle fusion and, after facilitating membrane merging, are supposed to return to their donor organelle for new rounds of fusion. However, little is known about this recycling. We have found that Stx8, a fungal SNARE similar to human syntaxin 8, is a retromer cargo, and have identified its retromer binding motif. Sequence screening and comparison has determined that this sorting motif is conserved mainly in fungal Stx8 sequences. Notably, this motif is similar to the retromer sorting motif that is present in a family of vertebrate ion transporters. Our initial phylogenetic analyses suggest that, although retromer and some of its cargoes are conserved, the sorting motif in the cargoes might have undergone evolutionary divergence. |
| Databáze: | OpenAIRE |
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