Functional divergence in heat shock response following rapid speciation of Fucus spp. in the Baltic Sea
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In the Baltic Sea, the broadly distributed brown alga Fucus vesiculosus coexists in sympatry over part of its range (south west Gulf of Bothnia) with the Baltic endemic F. radicans sp. nov, while further north in colder and lower-salinity areas of the Baltic F. radicans occurs alone (north west Gulf of Bothnia). F. radicans appears to have arisen via rapid speciation from F. vesiculosus within the recent history of the Baltic (ca. 7500 BP). Possible functional divergence between the two species was investigated by comparing stress-responsive gene expression in a common-garden experiment. The experiment used two allopatric populations of Fucus vesiculosus from the Skagerrak (North Sea) and Central Baltic, as well as F. radicans from the same Central Baltic site. The two species in sympatry displayed divergent heat shock responses, while F. vesiculosus populations from allopatric sites did not. F. radicans was more sensitive to heat shock at 25°C, either alone or together with high irradiance and desiccation, than Baltic or Skagerrak F. vesiculosus. The results indicate that rapid functional divergence in the inducible heat shock response has occurred between sympatric species on a timescale of thousands of years.
KeywordsLate Embryogenesis Abundant Heat Shock Response Desiccation Stressor Clonal Reproduction Allopatric Population
This work was supported by funding from FCT-FEDER (ADAPT—POCI-PPCDT/MAR/61105/2004), Portugal and the EU Network of Excellence Marine Genomics Europe (G.A.P.), and a PhD fellowship from FCT and ESF (A.L.). The authors are grateful to two anonymous reviewers for comments and suggestions that improved the manuscript.
- Beer S, Kautsky L (1992) The recovery of net photosynthesis during rehydration of Botanica Marina three Fucus species from the Swedish west coast following exposure to air. 35:487–491Google Scholar
- Donner J (1995) The quaternary history of Scandinavia. Cambridge University Press, CambridgeGoogle Scholar
- Ferl RJ, Manak MS, Reyes MF (2002) The 14-3-3s. Genome Biology 3: reviews3010.3011—reviews3010.3017. doi: 10.1186/gb-2002-3-7-reviews3010
- Ignatius H, Axberg S, Niemistö L, Winterhalter B (1981) Quaternary geology of the Baltic Sea. In: Voipio A (ed) The Baltic Sea. Elsevier Scientific, Amsterdam, pp 54–104Google Scholar
- Pearson GA, Hoarau G, Lago-Leston A, Coyer JA, Kube M, Reinhardt R, Henckel K, Serrão ETA, Corre E, Olsen JL (2009a) An expressed sequence tag analysis of the intertidal brown seaweeds Fucus serratus (L.) and F. vesiculosus (L.) (Heterokontophyta, Phaeophyceae) in response to abiotic stressors. Mar BiotechnolGoogle Scholar
- Siegel H, Gerth M, Tschersich G (2006) Sea surface temperature development of the Baltic Sea in the period 1990–2004. Oceanologia 48:119–131Google Scholar
- Waters ER, Lee GJ, Vierling E (1996) Evolution, structure and function of the small heat shock proteins in plants. J Exp Biol 47:325–338Google Scholar