Proteomic similarity of the Littorinid snails in the evolutionary context

Background The introduction of DNA-based molecular markers made a revolution in biological systematics. However, in cases of very recent divergence events, the neutral divergence may be too slow, and the analysis of adaptive part of the genome is more informative to reconstruct the recent evolutionary history of young species. The advantage of proteomics is its ability to reflect the biochemical machinery of life. It may help both to identify rapidly evolving genes and to interpret their functions. Methods Here we applied a comparative gel-based proteomic analysis to several species from the gastropod family Littorinidae. Proteomes were clustered to assess differences related to species, geographic location, sex and body part, using data on presence/absence of proteins in samples and data on protein occurrence frequency in samples of different species. Cluster support was assessed using multiscale bootstrap resampling and the stability of clustering—using cluster-wise index of cluster stability. Taxon-specific protein markers were derived using IndVal method. Proteomic trees were compared to consensus phylogenetic tree (based on neutral genetic markers) using estimates of the Robinson–Foulds distance, the Fowlkes–Mallows index and cophenetic correlation. Results Overall, the DNA-based phylogenetic tree and the proteomic similarity tree had consistent topologies. Further, we observed some interesting deviations of the proteomic littorinid tree from the neutral expectations. (1) There were signs of molecular parallelism in two Littoraria species that phylogenetically are quite distant, but live in similar habitats. (2) Proteome divergence was unexpectedly high between very closely related Littorina fabalis and L. obtusata, possibly reflecting their ecology-driven divergence. (3) Conservative house-keeping proteins were usually identified as markers for cryptic species groups (“saxatilis” and “obtusata” groups in the Littorina genus) and for genera (Littoraria and Echinolittorina species pairs), while metabolic enzymes and stress-related proteins (both potentially adaptively important) were often identified as markers supporting species branches. (4) In all five Littorina species British populations were separated from the European mainland populations, possibly reflecting their recent phylogeographic history. Altogether our study shows that proteomic data, when interpreted in the context of DNA-based phylogeny, can bring additional information on the evolutionary history of species

Metabolomes in sympatric populations of closely related species of the genus Littorina (Neritrema) in two sites in the Norwegian and Barents Sea

This zip file contains metabolomic data from gas chromatography mass-spectrometry analysis. Metabolites identification was done using fragmented spectra NIST (National Institute of Standards and Technology) database and standard chromatograms of single amino acids, monosaccharides, fatty acids manually and their mixtures

Microhabitat distribution in sympatric populations of closely related species of the genus Littorina (Neritrema) in two sites in the Norwegian and Barents Sea

This dataset contains microhabitat distribution data

Microhabitat distribution, shell shape, and metabolomes in sympatric populations of closely related species of the genus Littorina (Neritrema) in two sites in the Norwegian and Barents Sea

This study is devoted to microevolutionary processes in populations of marine snails of subgenus Neritrema (Gastropoda, Littorinidae). We analyzed the microhabitat distribution of 5 cryptic species of molluscs (Littorina saxatilis (Olivi, 1792); Littorina arcana Hannaford Ellis, 1978; Littorina compressa Jeffreys, 1865; Littorina obtusata (Linnaeus, 1758); Littorina fabalis (Turton, 1825)) within the intertidal zone and potentially related morphological and physiological characteristics. The data was collected at two geographic locations (Saltstraumen, Norwegian Sea, 66°58'10.2"N 13°58'26.5"E, collection dates 29.06-5.07.2019; Varangerfjord, Barents Sea, 70°04'03.9"N 29°58'40.1"E, collection dates 09.07-12.07.2019). Additional information may be found in the mentioned paper

Shell morphometry in sympatric populations of closely related species of the genus Littorina (Neritrema) in two sites in the Norwegian and Barents Sea

Folder Morphometry contains geometric morphometric data. The shell shape was described by 11 landmarks and 56 semilandmarks. In total, the analysis included: 126 individuals of L. saxatilis (50-141 mm), 32 individuals of L. arcana (81-130 mm), 47 individuals of L. compressa (61-113 mm), 128 individuals of L. obtusata (55-167 mm) and 41 individuals of L. fabalis (50-147 mm)