A comprehensive analysis of short specific tissue (SST) proteins, a new group of proteins from PF10950 that may give rise to cyclopeptide alkaloids

[EN] Proteins of the PF10950 family feature the DUF2775 domain of unknown function. The most studied are specific tissue (ST) proteins with tandem repeats, which are putative precursors of cyclopeptide alkaloids. Here, we study uncharacterised short ST (SST) proteins with the DUFF2775 domain by anal...

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Detalles Bibliográficos
Autores: Albornos, Lucía, Iriondo, Paula, Rodríguez Marcos, Silvia, Farelo, Patricia, Sobrino Mengual, Guillermo, Muñoz Centeno, Luz María, Martín Sánchez, José Ignacio, Dopico, Berta
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2025
País:España
Institución:Universidad de Salamanca (USAL)
Repositorio:GREDOS. Repositorio Institucional de la Universidad de Salamanca
OAI Identifier:oai:gredos.usal.es:10366/166998
Acceso en línea:http://hdl.handle.net/10366/166998
Access Level:acceso abierto
Palabra clave:DUF2775 domain
SST protein
ST protein
Root
Cyclopeptides alkaloids
PF10950
2417.03 Botánica General
2302.01 Alcaloides
Descripción
Sumario:[EN] Proteins of the PF10950 family feature the DUF2775 domain of unknown function. The most studied are specific tissue (ST) proteins with tandem repeats, which are putative precursors of cyclopeptide alkaloids. Here, we study uncharacterised short ST (SST) proteins with the DUFF2775 domain by analysing 194 sequences from 120 species of 39 taxonomic families in silico. SST proteins have a signal peptide and their size and several other characteristics depend on their individual taxonomic family. Sequence analyses revealed that SST proteins contain two well-conserved regions, one resembling the ST repeat, which could constitute the core of cyclopeptide alkaloids. We studied the unique SST1 gene of Arabidopsis thaliana, which is adjacent to and co-expressed with a gene encoding a protein with a BURP domain, associated with cyclopeptide production. The empirical analysis indicated that the SST1 promoter is mainly activated in the roots, where most of the transcripts accumulate, and that the SST1 protein accumulates in the root vascular cambium. At the cellular level, SST fused to GFP appears in vesicles that colocalise with the endoplasmic reticulum and the vacuole. Thus, SSTs are a new type of PF10950 protein found in core eudicots with two conserved regions that could be involved in root biology.