Phenotypic diversity, population structure and stress protein-based capacitoring in populations of Xeropicta derbentina, a heat-tolerant land snail species

• DOI: 10.1007/s12192-014-0503-x
• Publication Date: 2014-03-03T22:52:35Z
• Authors: Maddalena A. Di L...; Sergej Sereda; Anna Geißler; Adrien Picot; Petra Arnold; Stefanie Lang; Sandra Troschinski; Andreas Dieterich; Torsten Hauffe; Yvan Capowiez; Christophe Mazzia; Thomas Knigge; Tiphaine Monsinjon; Stefanie Krais; Thomas Wilke; Rita Triebskorn; Heinz-R. Köhler
• Keywords: [SDE] Environmental Sciences; 0301 basic medicine; 570; LIFE-HISTORY; Hot Temperature; HSP70 EXPRESSION; MORPHOLOGICAL VARIATION; Genotype; [SDV]Life Sciences [q-bio]; Acclimatization; Population Dynamics; Snails; 610; EXTREME TEMPERATURES; Hsp70; COI; Electron Transport Complex IV; Evolution, Molecular; 03 medical and health sciences; SHOCK-PROTEIN; Animal Shells; Animals; HSP70 Heat-Shock Proteins; PLASTICITY; Eco-devo; Pigmentation; R-PACKAGE; Genetic Variation; THEBA-PISANA PULMONATA; Adaptation, Physiological; [SDV] Life Sciences [q-bio]; Phenotype; DROSOPHILA-MELANOGASTER; [SDE]Environmental Sciences; Evolutionary capacitance; Xeropicta derbentina; Heat-Shock Response; NATURAL-POPULATIONS

The shell colour of many pulmonate land snail species is highly diverse. Besides a genetic basis, environmentally triggered epigenetic mechanisms including stress proteins as evolutionary capacitors are thought to influence such phenotypic diversity. In this study, we investigated the relationship of stress protein (Hsp70) levels with temperature stress tolerance, population structure and phenotypic diversity within and among different populations of a xerophilic Mediterranean snail species (Xeropicta derbentina). Hsp70 levels varied considerably among populations, and were significantly associated with shell colour diversity: individuals in populations exhibiting low diversity expressed higher Hsp70 levels both constitutively and under heat stress than those of phenotypically diverse populations. In contrast, population structure (cytochrome c oxidase subunit I gene) did not correlate with phenotypic diversity. However, genetic parameters (both within and among population differences) were able to explain variation in Hsp70 induction at elevated but non-pathologic temperatures. Our observation that (1) population structure had a high explanatory potential for Hsp70 induction and that (2) Hsp70 levels, in turn, correlated with phenotypic diversity while (3) population structure and phenotypic diversity failed to correlate provides empirical evidence for Hsp70 to act as a mediator between genotypic variation and phenotype and thus for chaperone-driven evolutionary capacitance in natural populations.