Stable genetic structure and connectivity in pollution-adapted and nearby pollution-sensitive populations of Fundulus heteroclitus .

Autor: Nunez JCB; Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Causeway, Miami, FL 33149, USA.; Department of Ecology and Evolutionary Biology, Brown University, 80 Waterman Street, Box G, Providence, RI 02912, USA., Biancani LM; Department of Ecology and Evolutionary Biology, Brown University, 80 Waterman Street, Box G, Providence, RI 02912, USA., Flight PA; Department of Ecology and Evolutionary Biology, Brown University, 80 Waterman Street, Box G, Providence, RI 02912, USA., Nacci DE; Population Ecology Branch, Atlantic Ecology Division, Office of Research and Development, US Environmental Protection Agency, 27 Tarzwell Drive, Narragansett, RI 02882, USA., Rand DM; Department of Ecology and Evolutionary Biology, Brown University, 80 Waterman Street, Box G, Providence, RI 02912, USA., Crawford DL; Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Causeway, Miami, FL 33149, USA., Oleksiak MF; Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Causeway, Miami, FL 33149, USA.
Jazyk: angličtina
Zdroj: Royal Society open science [R Soc Open Sci] 2018 May 09; Vol. 5 (5), pp. 171532. Date of Electronic Publication: 2018 May 09 (Print Publication: 2018).
DOI: 10.1098/rsos.171532
Abstrakt: Populations of the non-migratory estuarine fish Fundulus heteroclitus inhabiting the heavily polluted New Bedford Harbour (NBH) estuary have shown inherited tolerance to local pollutants introduced to their habitats in the past 100 years. Here we examine two questions: (i) Is there pollution-driven selection on the mitochondrial genome across a fine geographical scale? and (ii) What is the pattern of migration among sites spanning a strong pollution gradient? Whole mitochondrial genomes were analysed for 133 F. heteroclitus from seven nearby collection sites: four sites along the NBH pollution cline (approx. 5 km distance), which had pollution-adapted fish, as well as one site adjacent to the pollution cline and two relatively unpolluted sites about 30 km away, which had pollution-sensitive fish. Additionally, we used microsatellite analyses to quantify genetic variation over three F. heteroclitus generations in both pollution-adapted and sensitive individuals collected from two sites at two different time points (1999/2000 and 2007/2008). Our results show no evidence for a selective sweep of mtDNA in the polluted sites. Moreover, mtDNA analyses revealed that both pollution-adapted and sensitive populations harbour similar levels of genetic diversity. We observed a high level of non-synonymous mutations in the most polluted site. This is probably associated with a reduction in N e and concomitant weakening of purifying selection, a demographic expansion following a pollution-related bottleneck or increased mutation rates. Our demographic analyses suggest that isolation by distance influences the distribution of mtDNA genetic variation between the pollution cline and the clean populations at broad spatial scales. At finer scales, population structure is patchy, and neither spatial distance, pollution concentration or pollution tolerance is a good predictor of mtDNA variation. Lastly, microsatellite analyses revealed stable population structure over the last decade.
Competing Interests: We, the authors, have no competing interests.
Databáze: MEDLINE
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