Processive Recoding and Metazoan Evolution of Selenoprotein P: Up to 132 UGAs in Molluscs - Université de Pau et des Pays de l'Adour Access content directly
Journal Articles Journal of Molecular Biology Year : 2019

Processive Recoding and Metazoan Evolution of Selenoprotein P: Up to 132 UGAs in Molluscs

Janinah Baclaocos
  • Function : Author
Didac Santesmasses
  • Function : Author
Marco Mariotti
  • Function : Correspondent author
  • PersonId : 1053687

Connectez-vous pour contacter l'auteur
Michael Vetick
  • Function : Author
Sharon Lynch
  • Function : Author
Rob Mcallen
  • Function : Author
John Mackrill
  • Function : Author
Gary Loughran
  • Function : Author
Paul Copeland
  • Function : Author
Vadim Gladyshev
  • Function : Author
John F. Atkins
  • Function : Author


Selenoproteins typically contain a single selenocysteine, the 21st amino acid, encoded by a context-redefined UGA. However, human selenoprotein P (SelenoP) has a redox-functioning selenocysteine in its N-terminal domain and nine selenium transporter-functioning selenocysteines in its C-terminal domain. Here we show that diverse SelenoP genes are present across metazoa with highly variable numbers of Sec-UGAs, ranging from a single UGA in certain insects, to 9 in common spider, and up to 132 in bivalve molluscs. SelenoP genes were shaped by a dynamic evolutionary process linked to selenium usage. Gene evolution featured modular expansions of an ancestral multi-Sec domain, which led to particularly Sec-rich SelenoP proteins in many aquatic organisms. We focused on molluscs, and chose Pacific oyster Magallana gigas as experimental model. We show that oyster SelenoP mRNA with 46 UGAs is translated full-length in vivo. Ribosome profiling indicates that selenocysteine specification occurs with ~5% efficiency at UGA1 and approaches 100% efficiency at distal 3' UGAs. We report genetic elements relevant to its expression, including a leader open reading frame and an RNA structure overlapping the initiation codon that modulates ribosome progression in a seleniumdependent manner. Unlike their mammalian counterparts, the two SECIS elements in oyster SelenoP (3'UTR recoding elements) do not show functional differentiation in vitro. Oysters can increase their tissue selenium level up to 50-fold upon supplementation, which also results in extensive changes in selenoprotein expression.
Fichier principal
Vignette du fichier
Processive Recoding andMetazoan.pdf (3.38 Mo) Télécharger le fichier
Origin : Publisher files allowed on an open archive

Dates and versions

hal-02282676 , version 1 (17-11-2020)


Attribution - NonCommercial - NoDerivatives



Janinah Baclaocos, Didac Santesmasses, Marco Mariotti, Katarzyna Bierla, Michael Vetick, et al.. Processive Recoding and Metazoan Evolution of Selenoprotein P: Up to 132 UGAs in Molluscs. Journal of Molecular Biology, 2019, 431, pp.4381 - 4407. ⟨10.1016/j.jmb.2019.08.007⟩. ⟨hal-02282676⟩
48 View
114 Download



Gmail Facebook X LinkedIn More