Balanced Polymorphism at the Pgm-1 Locus of the Pompeii Worm Alvinella pompejana and Its Variant Adaptability Is Only Governed by Two QE Mutations at Linked Sites - Archive ouverte HAL Access content directly
Journal Articles Genes Year : 2022

Balanced Polymorphism at the Pgm-1 Locus of the Pompeii Worm Alvinella pompejana and Its Variant Adaptability Is Only Governed by Two QE Mutations at Linked Sites

(1) , (1) , (2) , (3) , , (4) , (5) , (1) , (1)
1
2
3
4
5

Abstract

The polychaete Alvinella pompejana lives exclusively on the walls of deep-sea hydrothermal chimneys along the East Pacific Rise (EPR), and displays specific adaptations to withstand the high temperatures and hypoxia associated with this highly variable habitat. Previous studies have revealed the existence of a balanced polymorphism on the enzyme phosphoglucomutase associated with thermal variations, where allozymes 90 and 100 exhibit different optimal activities and thermostabilities. Exploration of the mutational landscape of phosphoglucomutase 1 revealed the maintenance of four highly divergent allelic lineages encoding the three most frequent electromorphs over the geographic range of A. pompejana. This polymorphism is only governed by two linked amino acid replacements, located in exon 3 (E155Q and E190Q). A two-niche model of selection, including ‘cold’ and ‘hot’ conditions, represents the most likely scenario for the long-term persistence of these isoforms. Using directed mutagenesis and the expression of the three recombinant variants allowed us to test the additive effect of these two mutations on the biochemical properties of this enzyme. Our results are coherent with those previously obtained from native proteins, and reveal a thermodynamic trade-off between protein thermostability and catalysis, which is likely to have maintained these functional phenotypes prior to the geographic separation of populations across the Equator about 1.2 million years ago.
Fichier principal
Vignette du fichier
Bioy_et_al2022_HAL.pdf (2.33 Mo) Télécharger le fichier
Origin : Files produced by the author(s)

Dates and versions

hal-03770877 , version 1 (12-11-2019)
hal-03770877 , version 2 (06-09-2022)

Identifiers

Cite

Alexis Bioy, Anne-Sophie Le Port, Emeline Sabourin, Marie Verheye, Patrice Piccino, et al.. Balanced Polymorphism at the Pgm-1 Locus of the Pompeii Worm Alvinella pompejana and Its Variant Adaptability Is Only Governed by Two QE Mutations at Linked Sites. Genes, 2022, 13 (2), pp.206. ⟨10.3390/genes13020206⟩. ⟨hal-03770877v2⟩
55 View
81 Download

Altmetric

Share

Gmail Facebook Twitter LinkedIn More