MEPS 552:177-193 (2016)  -  DOI: https://doi.org/10.3354/meps11770

ABSTRACT:  During recent years, the role of proteomics in ecology, population biology and evolutionary studies has been growing. It has been used effectively to resolve taxonomic ambiguity in closely related species and for detection of environmental effects on populations. The family Littorinidae (Gastropoda; periwinkles) includes a set of widely distributed species, which are important members of intertidal communities of the coasts around the world. Taxonomic relationships among several species, e.g. within the subgenus Neritrema, are still poorly understood. We explored proteomes of 3 closely related littorinid species (the so called ‘saxatilis’-group: Littorina arcana, L. compressa and L. saxatilis) from different tidal levels of one geographic area. The proteome data were obtained using 2-dimensional difference gel electrophoresis (2D-DIGE) followed by mass spectrometry for protein identification. We showed that L. compressa formed a well-supported clade within the ‘saxatilis’ group, while L. arcana and L. saxatilis had similar proteomes. In contrast to L. compressa, the variable elements in the proteomes of the 2 latter species shifted similarly along the vertical shore gradient. Such proteomic divergence suggests that closely related species may function differently at the physiological level under very similar conditions.

KEY WORDS: Littorina · ‘Littorina saxatilis’ species complex · Cryptic species · Proteomics ·  2D difference gel electrophoresis · 2D-DIGE · Speciation