Transcriptomic analysis illuminates genes involved in chlorophyll synthesis after nitrogen starvation in Acaryochloris sp. CCMEE 5410.
Acaryochloris species are a genus of cyanobacteria that utilize chlorophyll (chl) d as their primary chlorophyll molecule during oxygenic photosynthesis. Chl d allows Acaryochloris to harvest red-shifted light, which gives them the ability to live in filtered light environments that are depleted in visible light. Although genomes of multiple Acaryochloris species have been sequenced, their analysis has not revealed how chl d is synthesized. Here, we demonstrate that Acaryochloris sp. CCMEE 5410 cells undergo chlorosis by nitrogen depletion and exhibit robust regeneration of chl d by nitrogen repletion. We performed a time course RNA-Seq experiment to quantify global transcriptomic changes during chlorophyll recovery. We observed upregulation of numerous known chl biosynthesis genes and also identified an oxygenase gene with a similar transcriptional profile as these chl biosynthesis genes, suggesting its possible involvement in chl d biosynthesis. Moreover, our data suggest that multiple prochlorophyte chlorophyll-binding homologs are important during chlorophyll recovery, and light-independent chl synthesis genes are more dominant than the light-dependent gene at the transcription level. Transcriptomic characterization of this organism provides crucial clues toward mechanistic elucidation of chl d biosynthesis.
Department of Pathology, Washington University in St. Louis School of Medicine, St. Louis, MO, USA.|Center for Genome Sciences and Systems Biology, Washington University in St. Louis School of Medicine, St. Louis, MO, USA.
Aki
A
Yoneda
Department of Biology, Washington University in St. Louis, St. Louis, MO, USA.|Photosynthetic Antenna Research Center (PARC), Washington University in St. Louis, St. Louis, MO, USA.
Bruce J
BJ
Wittmann
Department of Biology, Washington University in St. Louis, St. Louis, MO, USA.|Photosynthetic Antenna Research Center (PARC), Washington University in St. Louis, St. Louis, MO, USA.
Jeremy D
JD
King
Department of Biology, Washington University in St. Louis, St. Louis, MO, USA. blankenship@wustl.edu.|Photosynthetic Antenna Research Center (PARC), Washington University in St. Louis, St. Louis, MO, USA. blankenship@wustl.edu.|Department of Chemistry, Washington University in St. Louis, St. Louis, MO, USA. blankenship@wustl.edu.
Robert E
RE
Blankenship
Department of Pathology, Washington University in St. Louis School of Medicine, St. Louis, MO, USA. dantas@wustl.edu.|Center for Genome Sciences and Systems Biology, Washington University in St. Louis School of Medicine, St. Louis, MO, USA. dantas@wustl.edu.|Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO, USA. dantas@wustl.edu.|Department of Molecular Microbiology, Washington University in St. Louis School of Medicine, St. Louis, MO, USA. dantas@wustl.edu.
Gautam
http://orcid.org/0000-0003-0455-8370
G
Dantas
D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D002734:Chlorophyll / Q000378:metabolism*; D000458:Cyanobacteria / Q000235:genetics* / Q000378:metabolism; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D059014:High-Throughput Nucleotide Sequencing; D008027:Light; D009584:Nitrogen / Q000172:deficiency / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism; D010105:Oxygenases / Q000235:genetics / Q000378:metabolism*; D010788:Photosynthesis; D017423:Sequence Analysis, RNA
D001426:Bacterial Proteins; D002734:Chlorophyll; C107509:chlorophyll d; D010105:Oxygenases; D009584:Nitrogen; D010100:Oxygen
Acaryochloris; Chlorophyll d; Nitrogen recovery; Nitrogen starvation; RNA-Seq; Transcriptomics