CHROMOVAR · A chromosome marker for natural and anthropogenic change in the predatory marine gastropod Nucella lapillus (L.)
6РП — Действия „Мария Кюри“
- Период
- 2005-12-01 → 2007-11-30
- Финансиране от ЕС
- 167 664 €
- Участници
- 1
- Схема
- EIF
Линиите свързват координатора с партньорите. За проекти отпреди 2014 г. CORDIS не винаги дава точни координати. Тези точки са на ниво град или държава.
Накратко на български
Разликите в броя и структурата на хромозомите при морските охлюви Nucella lapillus влияят на способността им за размножаване. Това помага да се разбере как се формират нови видове без географска изолация и как организмите се адаптират към промените в средата.
Кратко обяснение, генерирано от езиков модел по текста на CORDIS. Оригиналът е по-долу.
Резултати накратко
Final Activity Report Summary - CHROMOVAR (A chromosome marker for natural and anthropogenic change in the predatory marine gastropod Nucella lapillus (L.))
Changes in chromosome number based on centromere fusion or fission (Robertsonian polymorphism) in the common dog-whelk Nucella lapillus results in striking chromosome number differences at different localities on the French and English Channel coasts. This simple numerical variation has been accompanied by chromosomal inversions and other structural re-arrangements that have the potential to act as post-mating barriers to limit cross-breeding between chromosomally dissimilar forms. Hence, whilst the European dog-whelk appears to be a single species across its whole range, from Norway to Portugal, it may hold within its cells the secret of how different species may arise without geographic isolation through subtle changes in chromosome structure and number. Focusing on dog-whelks with diploid chromosome numbers of 2n = 26 and 2n = 36, we have shown using laboratory breeding experiments that the number of offspring hatching from crosses between the two types is reduced compared to crosses within each pure parental form. While reproductive output was lowest in hybrid crosses involving female 2n=36 individuals (i.e. crossed with a male 2n = 26), the reciprocal cross involving a female 2n=26 form performed as well in terms of reproductive output as those where both parents were 2n=26. This strongly supports the existence of a partial barrier to cross breeding between these chromosomally distinct forms, at least in one direction. Whether this barrier is immunological (sperm recognition), allelic (genes) or chromosomal (meiotic instability) remains to be identified, but this points to the subtle barriers to cross breeding that may eventually result in local speciation and/or adaptation. In a world threatened by accelerated climate change, it is essential that we understand more about those intrinsic mechanisms that act as barriers/corridors affecting the rates of genetic exchange within and between populations. Our research findings suggest that the humble dog-whelk, with its intriguing chromosome polymorphism, may hold the key to unravelling the mysteries of evolution on a micro-scale, which may offer important insights into how populations of marine organisms adapt and survive under conditions of environmental change.
Текст от CORDIS, на английски · Данни: CORDIS, © Европейски съюз
Цел на проекта
Nucella lapillus (L.) provides an ideal model for investigating the role of chromosome change in ecological adaptation. It is widely distributed on NE Atlantic coasts, stretching from Northern Norway to Southern Portugal. Dog-whelks on French and English Channel coasts exhibit a numerical chromosome polymorphism, which is highly unusual in showing a correlation with the degree of wave action on the shore, which suggests an adaptive role. This chromosome number variation is accompanied by structural chromoso mal arrangements (inversions and translocations) with the potential to free up functional gene complexes for local selection. Nucella lapillus has featured prominently in studies of tributyltin (TBT) antifouling paints (imposex). There is evidence that a c hromosomal variant may play a protective role in relation to antifouling paint residues. The project will address the question of chromosomal variation in Nucella as a mechanism for adaptation to different thermal environments. Given that the polymorphism was first reported on the French Channel coast six decades ago, and is still present despite the damaging effects of TBT, this provides a unique opportunity to study how chromosome change influences local adaptive capability, and hence the long-term survival of an ecologically important invertebrate species on European shores. The objectives are to use state of the Art molecular and cytological methods, coupled with fine scale shore sampling and laboratory breeding experiments, to test the nature and role o f chromosome change in effecting local adaptation. These investigations will be supported by the expertise and facilities at the Marine Biological Association and Roscoff Marine Laboratory. Nucella lapillus has already been identified a key species by t he Marine Genomics Network of Excellence, and the project will yield findings relevant to the Framework 6 Global Change and Ecosystems Thematic Priority.
Оригинален текст от CORDIS (на английски).
Участници
- MARINE BIOPLOGICAL ASSOCIATION OF THE UNITED KINGDOM · PLYMOUTHКоординаторНиво градОбединеното кралство
Връзки
Данни: CORDIS, © Европейски съюз