Arabidopsis ATXR2 represses de novo shoot organogenesis in the transition from callus to shoot formation

Kyounghee Lee; Ok-Sun Park; Ji Yun Go; Jihyeon Yu; Jun Hee Han; Jungmook Kim; Sangsu Bae; Yu Jin Jung; Pil Joon Seo

doi:10.1016/j.celrep.2021.109980

Arabidopsis ATXR2 represses de novo shoot organogenesis in the transition from callus to shoot formation

Cell Rep. 2021 Nov 9;37(6):109980. doi: 10.1016/j.celrep.2021.109980.

Authors

Kyounghee Lee¹, Ok-Sun Park², Ji Yun Go³, Jihyeon Yu⁴, Jun Hee Han⁴, Jungmook Kim⁵, Sangsu Bae⁴, Yu Jin Jung³, Pil Joon Seo⁶

Affiliations

¹ Department of Chemistry, Seoul National University, Seoul 08826, Korea; Research Institute of Basic Sciences, Seoul National University, Seoul 08826, Korea.
² Plant Genomics and Breeding Institute, Seoul National University, Seoul 08826, Korea.
³ Division of Horticultural Biotechnology, Hankyong National University, Anseong 17579, Korea.
⁴ Department of Chemistry and Research Institute for Convergence of Basic Sciences, Hanyang University, Seoul 04763, Korea.
⁵ Department of Bioenergy Science and Technology and Department of Integrative Food, Bioscience and Biotechnology, Chonnam National University, Gwangju 61186, Korea.
⁶ Department of Chemistry, Seoul National University, Seoul 08826, Korea; Research Institute of Basic Sciences, Seoul National University, Seoul 08826, Korea; Plant Genomics and Breeding Institute, Seoul National University, Seoul 08826, Korea. Electronic address: pjseo1@snu.ac.kr.

PMID: 34758306
DOI: 10.1016/j.celrep.2021.109980

Abstract

Plants exhibit high regenerative capacity, which is controlled by various genetic factors. Here, we report that ARABIDOPSIS TRITHORAX-RELATED 2 (ATXR2) controls de novo shoot organogenesis by regulating auxin-cytokinin interaction. The auxin-inducible ATXR2 Trithorax Group (TrxG) protein temporally interacts with the cytokinin-responsive type-B ARABIDOPSIS RESPONSE REGULATOR 1 (ARR1) at early stages of shoot regeneration. The ATXR2-ARR1 complex binds to and deposits the H3K36me3 mark in the promoters of a subset of type-A ARR genes, ARR5 and ARR7, thus activating their expression. Consequently, the ATXR2/ARR1-type-A ARR module transiently represses cytokinin signaling and thereby de novo shoot regeneration. The atxr2-1 mutant calli exhibit enhanced shoot regeneration with low expression of ARR5 and ARR7, which ultimately upregulates WUSCHEL (WUS) expression. Thus, ATXR2 regulates cytokinin signaling and prevents premature WUS activation to ensure proper cell fate transition, and the auxin-cytokinin interaction underlies the initial specification of shoot meristem in callus.

Keywords: Auxin-cytokinin interaction; callus; de novo shoot organogenesis; histone modification; plant regeneration.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Arabidopsis / cytology*
Arabidopsis / genetics
Arabidopsis / metabolism
Arabidopsis Proteins / genetics
Arabidopsis Proteins / metabolism*
Cytokinins / metabolism*
DNA-Binding Proteins / genetics
DNA-Binding Proteins / metabolism
Gene Expression Regulation, Plant*
Indoleacetic Acids / metabolism*
Methyltransferases / genetics
Methyltransferases / metabolism
Organogenesis*
Plant Shoots / cytology*
Plant Shoots / genetics
Plant Shoots / metabolism
Promoter Regions, Genetic
Regeneration
Signal Transduction
Transcription Factors / genetics
Transcription Factors / metabolism

Substances

ARR1 protein, Arabidopsis
Arabidopsis Proteins
Cytokinins
DNA-Binding Proteins
Indoleacetic Acids
Transcription Factors
Methyltransferases