Background:?
The green lineage comprises the most dominant groups of primary producers on earth. These organisms evolved after the joining of a cyanobacterium and a heterotrophic eukaryote. The green lineage includes the green algae (unicellular and seaweeds) and land plants. Land plants are the major components of terrestrial ecosystems, while the green algae have conquered oceanic, freshwater and terrestrial ecosystems. In oceanic waters, photosynthetic picoplanktonic eukaryotes (cells with size below 3 ?m) dominate primary production and biomass where eukaryotic pico-phytoplankton cells essentially consist of green algae from the prasinophyte lineage. By forming persistent background populations, they are critical for the maintenance of major biogeochemical cycles (e.g., carbon cycle).
Phylogenomics and comparative genomics act as lenses into the past, providing us with ways to identify the genomic innovations and environmental/genetic trade offs that led to the diversity and success of green algae. However, genomics research on unicellular marine green algae is far from having reached its full potential, and there is currently a significant bias in sequenced representatives that hampers our understanding of their diversity as well as their role in the environment. Despite thousands of described species (6878 catalogued in AlgaeBase) from 13 different lineages, only 89 Chlorophyta nuclear genomes are available in GenBank. Of these, more than 80% are restricted to two groups of organisms that either serve as model systems (e.g. Chlamydomonas reinhardtii) or are considered of economic importance (e.g. Chlorella and Nannochloris).
What do we want to accomplish?
The key objective of this project is to improve our understanding of the evolution of genome architectures, gene sequences, and metabolic capacities across the Chlorophyta.
How do we want to achieve our goal?
We propose to fill the gap in genomic research of marine green algae by generating and analyzing genomes from under-represented unicellular lineages, found in contrasting oceanic conditions and with small (1N?) and large (2N?) genome sizes. Reference nuclear genomes from distinct species have been and will be obtained i