An Artificial Conversion of Roots into Organs with Shoot Stem Characteristics by Inducing Two Transcription Factors

• Main Authors: Shigeru Hanano, Hajime Tomatsu, Ai Ohnishi, Koichi Kobayashi, Yuki Kondo, Shigeyuki Betsuyaku, Eiji Takita, Yoshiyuki Ogata, Keishi Ozawa, Kunihiro Suda, Tsutomu Hosouchi, Takahiro Nagase, Hideyuki Suzuki, Nozomu Sakurai, Hiroshi Masumoto, Hiroo Fukuda, Daisuke Shibata
• Format: Article
• Language: English
• Published: Elsevier 2020-07-01
• Series: iScience
• Subjects: Plant Biology; Plant Genetics; Plant Development
• Online Access: http://www.sciencedirect.com/science/article/pii/S2589004220305198

Summary: Somatic plant cells can regenerate shoots and/or roots or adventitious embryonic calluses, which may induce organ formation under certain conditions. Such regenerations occur via dedifferentiation of somatic cells, induction of organs, and their subsequent outgrowth. Despite recent advances in understanding of plant regeneration, many details of shoot induction remain unclear. Here, we artificially induced shoot stem-like green organs (SSOs) in Arabidopsis thaliana roots via simultaneous induction of two transcription factors (TFs), ARABIDOPSIS THALIANA HOMEOBOX PROTEIN 25 (ATHB25, At5g65410) and the B3 family transcription factor REPRODUCTIVE MERISTEM 7 (REM7, At3g18960). The SSOs exhibited negative gravitropism and differentiated vascular bundle phenotypes. The ATHB25/REM7 induced the expression of genes controlling shoot stem characteristics by ectopic expression in roots. Intriguingly, the restoration of root growth was seen in the consecutive and adjacent parts of the SSOs under gene induction conditions. Our findings thus provide insights into the development and regeneration of plant shoot stems.