Partner 2 - Institut de Ciences del Mar - Achievements

Partner 2 - Dr. Ramon Massana and team, ICM, CSIC, Barcelona, Spain

P2 analyzed biodiversity patterns in the basal lineages within the stramenopiles and amongst all marine eukaryotes. Main achievements consist in:

  • Phylogenetic and ecological analysis of Marine Stramenopiles (MAST) ribogroups. The BioMarKs genetic dataset was used to refine the analysis of MAST ribogroups across cell sizes, geographical sites, and habitats, validating the abundance and widespread distribution of virtually all MAST ribogroups and helping to define several new ones (Logares et al. 2012, Massana et al. 2013).
  • Study of genetic diversity within MAST-4. The MAST-4 ribogroup has received particular attention due to its widespread distribution and abundance. Previous information suggested that it had low genetic diversity. BioMarKs NGS data has increased 10 times the number of available MAST-4 sequences and confirmed its relatively lower diversity (Rodríguez-Martínez et al.  2012).
  • In-depth overview of marine protistan diversity along the EU coast-line. P2 is leading a consortium effort aiming at qualifying and quantifying overall protistan diversity along the EU coastline (Massana et al. in prep.). Total protistan ribosomal diversity is organized in terms of taxonomy, cell-structure, and basic ecology (Fig 1).

Figure 1. Distribution of total rDNA diversity across main eukaryotic lineages, cell-size ranges, and environment (plankton versus benthos).

  • NGS analysis of the rare protistan biosphere. P2 led a consortium study using most BioMarKs NGS 454 and Illumina sequencing data to analyze patterns of rare versus abundant protistan communities. Results show regular proportions of abundant and rare microeukaryotes across space and time and contrasting structuring patterns in abundant and rare regional communities (Logares et al., in press).
  • Comparative taxonomic analysis of environmental DNA and RNA surveys. Clear differences in protistan diversity derived from e-DNA or e-RNA surveys were shown on local scales, but the results have not been systematized across large geographic and taxonomical scales. The BioMarKs dataset allows unique quantification of these differences revealing some groups that are detected at similar levels in both DNA and RNA (e.g. the diatoms in Fig. 2), while others are more represented in either e-DNA (MALV-I) or in e-RNA surveys (Chrysophytes).  P1 and P2 are working on a consortium paper to describe these patterns (Gobet et al. in prep).

Figure 2. Comparative abundance of ribosomal OTUs retrieved from DNA and RNA surveys of total protistan biodiversity.