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A genome-wide algal mutant library and functional screen identifies genes required for eukaryotic photosynthesis.

ABSTRACT: Photosynthetic organisms provide food and energy for nearly all life on Earth, yet half of their protein-coding genes remain uncharacterized1,2. Characterization of these genes could be greatly accelerated by new genetic resources for unicellular organisms. Here we generated a genome-wide, indexed library of mapped insertion mutants for the unicellular alga Chlamydomonas reinhardtii. The 62,389 mutants in the library, covering 83% of nuclear protein-coding genes, are available to the community. Each mutant contains unique DNA barcodes, allowing the collection to be screened as a pool. We performed a genome-wide survey of genes required for photosynthesis, which identified 303 candidate genes. Characterization of one of these genes, the conserved predicted phosphatase-encoding gene CPL3, showed that it is important for accumulation of multiple photosynthetic protein complexes. Notably, 21 of the 43 higher-confidence genes are novel, opening new opportunities for advances in understanding of this biogeochemically fundamental process. This library will accelerate the characterization of thousands of genes in algae, plants, and animals.

SUBMITTER: Li X

PROVIDER: S-EPMC6636631 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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A genome-wide algal mutant library and functional screen identifies genes required for eukaryotic photosynthesis.

Li Xiaobo X Patena Weronika W Fauser Friedrich F Jinkerson Robert E RE Saroussi Shai S Meyer Moritz T MT Ivanova Nina N Robertson Jacob M JM Yue Rebecca R Zhang Ru R Vilarrasa-Blasi Josep J Wittkopp Tyler M TM Ramundo Silvia S Blum Sean R SR Goh Audrey A Laudon Matthew M Srikumar Tharan T Lefebvre Paul A PA Grossman Arthur R AR Jonikas Martin C MC

Nature genetics 20190318 4

Photosynthetic organisms provide food and energy for nearly all life on Earth, yet half of their protein-coding genes remain uncharacterized<sup>1,2</sup>. Characterization of these genes could be greatly accelerated by new genetic resources for unicellular organisms. Here we generated a genome-wide, indexed library of mapped insertion mutants for the unicellular alga Chlamydomonas reinhardtii. The 62,389 mutants in the library, covering 83% of nuclear protein-coding genes, are available to the ...[more]

PMID: 30886426

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A genome-wide algal mutant library and functional screen identifies genes required for eukaryotic photosynthesis.

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A genome-wide algal mutant library and functional screen identifies genes required for eukaryotic photosynthesis.

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