Convergent recruitment of TALE homeodomain life cycle regulators to direct sporophyte development in land plants and brown algae
- French National Centre for Scientific Research, France
- Bezhin Rosko, France
- Collège de France, France
- Institut National de la Recherche Agronomique, France
Abstract
Three amino acid loop extension homeodomain transcription factors (TALE HD TFs) act as life cycle regulators in green algae and land plants. In mosses these regulators are required for the deployment of the sporophyte developmental program. We demonstrate that mutations in either of two TALE HD TF genes, OUROBOROS or SAMSARA, in the brown alga Ectocarpus result in conversion of the sporophyte generation into a gametophyte. The OUROBOROS and SAMSARA proteins heterodimerise in a similar manner to TALE HD TF life cycle regulators in the green lineage. These observations demonstrate that TALE-HD-TF-based life cycle regulation systems have an extremely ancient origin, and that these systems have been independently recruited to regulate sporophyte developmental programs in at least two different complex multicellular eukaryotic supergroups, Archaeplastida and Chromalveolata.
Data availability
All the sequencing data that has been generated by or used in this study is described in Supplementary file 9. SRA accession numbers are provided for all samples. Genbank accession numbers for the corrected ORO and SAM genes are provided in the results section.
Article and author information
Author details
Funding
Centre National de la Recherche Scientifique
- Alok Arun
- Susana M Coelho
- Akira F Peters
- Simon Bourdareau
- Laurent Pérès
- Delphine Scornet
- Martina Strittmatter
- Agnieszka P Lipinska
- Haiqin Yao
- Olivier Godfroy
- Gabriel J Montecinos
- Komlan Avia
- Nicolas Macaisne
- Christelle Troadec
- Abdelhafid Bendahmane
- J Mark Cock
European Research Council (ERC-SEXYPARTH)
- Abdelhafid Bendahmane
Agence Nationale de la Recherche (ANR-10-BLAN-1727)
- J Mark Cock
Interreg Program France -England (Marinexus)
- J Mark Cock
University Pierre and Marie Curie
- Alok Arun
- Susana M Coelho
- Akira F Peters
- Simon Bourdareau
- Laurent Pérès
- Delphine Scornet
- Martina Strittmatter
- Agnieszka P Lipinska
- Haiqin Yao
- Olivier Godfroy
- Gabriel J Montecinos
- Komlan Avia
- Nicolas Macaisne
- J Mark Cock
European Research Council (638240)
- Susana M Coelho
European Erasmus Mundus program
- J Mark Cock
China Scholarship Council
- J Mark Cock
Agence Nationale de la Recherche (ANR-10-BTBR-04-01)
- J Mark Cock
Agence Nationale de la Recherche (ANR-10-LABX-40)
- Abdelhafid Bendahmane
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2019, Arun et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Convergent recruitment of TALE homeodomain life cycle regulators to direct sporophyte development in land plants and brown algae
eLife 8:e43101.
https://doi.org/10.7554/eLife.43101
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