Aberrant light sensing and motility in the green alga from the ice-covered Antarctic Lake Bonney.

The Antarctic green alga is an obligate psychrophile and an emerging model for photosynthetic adaptation to extreme conditions. Endemic to the ice-covered Lake Bonney, this alga thrives at highly unusual light conditions characterized by very low light irradiance (<15 μmol m s), a narrow wavelength spectrum enriched in blue light, and an extreme photoperiod. Genome sequencing of exposed an unusually large genome, with hundreds of highly similar gene duplicates and expanded gene families, some of which could be aiding its survival in extreme conditions.