A Transcriptome Atlas of Physcomitrella patens Provides Insights into the Evolution and Development of Land Plants

• Published in: Molecular plant 2016-02, Vol.9 (2), p.205-220
• Main Authors: Ortiz-Ramírez, Carlos, Hernandez-Coronado, Marcela, Thamm, Anna, Catarino, Bruno, Wang, Mingyi, Dolan, Liam, Feijó, José A., Becker, Jörg D.
• Format: Article
• Language: English
• Subjects: branching; Bryopsida - classification; Bryopsida - genetics; Bryopsida - metabolism; Evolution, Molecular; Gene Expression Regulation, Plant; land plant evolution; Physcomitrella patens; Plant Proteins - genetics; Plant Proteins - metabolism; TCP; tip growth; Transcriptome; transcriptome atlas; 功能基因; 小立碗藓; 苔藓植物; 被子植物; 转录因子; 进化; 阿特拉斯; 陆地植物
• ISSN: 1674-2052; 1752-9867
• DOI: 10.1016/j.molp.2015.12.002

Identifying the genetic mechanisms that underpin the evolution of new organ and tissue systems is an aim of evolutionary developmental biology. Comparative functional genetic studies between angiosperms and bryophytes can define those genetic changes that were responsible for developmental innovations. Here, we report the generation of a transcriptome atlas covering most phases in the life cycle of the model bryo- phyte Physcomitrella patens, including detailed sporophyte developmental progression. We identified a comprehensive set of sporophyte-specific transcription factors, and found that many of these genes have homologs in angiosperms that function in developmental processes such as flowering and shoot branching. Deletion of the PpTCP5 transcription factor results in development of supernumerary sporangia attached to a single seta, suggesting that it negatively regulates branching in the moss sporophyte. Given that TCP genes repress branching in angiosperms, we suggest that this activity is ancient. Finally, compar- ison of P. patens and Arabidopsis thaliana transcriptomes led us to the identification of a conserved core of transcription factors expressed in tip-growing cells. We identified modifications in the expression patterns of these genes that could account for developmental differences between P. patens tip-growing cells and A. thaliana pollen tubes and root hairs.