Journal Article

Clonal expansion behind a marine diatom bloom

Procaccini, Gabriele, D'Alelio, Domenico, Vitale, Laura, Montresor, Marina, Ruggiero, Maria Valeria, Santoro, Mariano, Ferrante, Maria Immacolata

2018

Overview

Genetic diversity is what selection acts on, thus shaping the adaptive potential of populations. We studied micro-evolutionary patterns of the key planktonic diatom Pseudo-nitzschia multistriata at a long-term sampling site over 2 consecutive years by genotyping isolates with 22 microsatellite markers. We show that both sex and vegetative growth interplay in shaping intraspecific diversity. We document a brief but massive demographic and clonal expansion driven by strains of the same mating type. The analysis of an extended data set (6 years) indicates that the genetic fingerprint of P. multistriata changed over time with a nonlinear pattern, with intermittent periods of weak and strong diversification related to the temporary predominance of clonal expansions over sexual recombination. These dynamics, rarely documented for phytoplankton, contribute to the understanding of bloom formation and of the mechanisms that drive microevolution in diatoms.

• Publisher: Nature Publishing Group UK,Oxford University Press,Nature Publishing Group
• Subject: 631/158/1745 / 631/181/457 / 631/208/457 / Asexual reproduction / Automation / Biological Evolution / Cell division / Datasets / Demographics / Diatoms - genetics / Diatoms - growth & development / Diatoms - isolation & purification / Ecology / Evolution / Evolutionary Biology / Genetic diversity / Genetic markers / Genetic Variation / Genomes / Genotyping / Life Sciences / Marine ecology / Marine microorganisms / Mating / Microbial Ecology / Microbial Genetics and Genomics / Microbiology / Microsatellite Repeats / Microsatellites / Original / original-article / Phytoplankton / Phytoplankton - genetics / Phytoplankton - growth & development / Phytoplankton - isolation & purification / Population / Population studies / Recombination / Software