Pseudo-nitzschia pungens (Bacillariophyceae): A cosmopolitan diatom species?

Casteleyn, Griet; Chepurnov, Victor A.; Leliaert, Frédérik; Mann, David G.; Bates, Stephen S.; Lundholm, Nina; Rhodes, Lesley; Sabbe, Koen; Vyverman, Wim

doi:10.1016/j.hal.2007.08.004

Cited by 135 publications

(168 citation statements)

References 56 publications

(91 reference statements)

Supporting

Mentioning

127

Contrasting

Unclassified

Order By: Relevance

“…We used the obligate sexual planktonic pennate diatom Pseudo-nitzschia pungens sensu lato to study gene flow on a global scale because (i) the species complex has been reported worldwide (31); (ii) it is known to form extensive blooms (32,33) and thus large population sizes that could facilitate gene flow at macrogeographic scales; and (iii) its life history, taxonomy, and biogeography have been well studied (34,35). Within P. pungens, both nuclear rDNA internal transcribed spacer (ITS) and plastid-encoded rbcL sequences have revealed the existence of three distinct clades (I-III), which are also distinguishable by subtle but clear differences in frustule ultrastructure.…”

mentioning

confidence: 99%

“…Within P. pungens, both nuclear rDNA internal transcribed spacer (ITS) and plastid-encoded rbcL sequences have revealed the existence of three distinct clades (I-III), which are also distinguishable by subtle but clear differences in frustule ultrastructure. Although these clades are currently recognized as subspecific taxa (varieties), the observed genetic and morphological discontinuities suggest that these clades behave as independent evolutionary lineages (36), hence justifying their recognition as discrete species-lineages within a planktonic superspecies P. pungens (35,37). To avoid confusion, we refer to these three taxa as clades I-III.…”

mentioning

confidence: 99%

“…To avoid confusion, we refer to these three taxa as clades I-III. The clades differ markedly in their geographical distribution (35) (Fig. 1).…”

mentioning

confidence: 99%

“…Although clades I and II are genetically well-differentiated, occasional hybrids between both clades have been recorded in the northeastern Pacific (38)(39)(40), suggesting incomplete reproductive isolation. Within clade I, all individuals have identical ITS and rbcL sequences and isolates from geographically widely separated populations reproduce sexually under laboratory conditions, suggesting the potential for gene flow between distant, or even transoceanic, populations (35,39). Therefore, clade I is well-suited to explore patterns of population genetic structuring and to evaluate gene flow over a range of geographical scales.…”

mentioning

confidence: 99%

“…We analyzed isolates from different localities in the Atlantic and Pacific Ocean to test the assumption that clade I represents a single globally panmictic population (35). Using a calibrated phylogenetic analysis we estimated the maximal divergence times between different populations of this clade, providing a historical framework to interpret patterns of gene flow and population differentiation.…”

mentioning

confidence: 99%

See 4 more Smart Citations

Limits to gene flow in a cosmopolitan marine planktonic diatom

Casteleyn

Leliaert

Backeljau

et al. 2010

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

206

175

View full text Add to dashboard Cite

The role of geographic isolation in marine microbial speciation is hotly debated because of the high dispersal potential and large population sizes of planktonic microorganisms and the apparent lack of strong dispersal barriers in the open sea. Here, we show that gene flow between distant populations of the globally distributed, bloom-forming diatom species Pseudo-nitzschia pungens (clade I) is limited and follows a strong isolation by distance pattern. Furthermore, phylogenetic analysis implies that under appropriate geographic and environmental circumstances, like the pronounced climatic changes in the Pleistocene, population structuring may lead to speciation and hence may play an important role in diversification of marine planktonic microorganisms. A better understanding of the factors that control population structuring is thus essential to reveal the role of allopatric speciation in marine microorganisms.allopatric speciation | dispersal | marine cosmopolitan planktonic microorganisms | population structure | microsatellites

show abstract

mentioning

confidence: 99%

mentioning

confidence: 99%

“…To avoid confusion, we refer to these three taxa as clades I-III. The clades differ markedly in their geographical distribution (35) (Fig. 1).…”

mentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%