title: A Two-Step Model for de Novo Activation ofWUSCHELduring Plant Shoot Regeneration.
abstract: Plant cells are totipotent and competent to regenerate from differentiated organs. It has been known for six decades that cytokinin-rich medium induces shoot regeneration from callus cells. However, the underlying molecular mechanism remains elusive. The homeodomain transcription factor WUSCHEL (WUS) is essential for de novo establishment of the shoot stem cell niche inArabidopsis thalianaWe found that WUS-positive (WUS+) cells mark the shoot progenitor region during regeneration. A cytokinin-rich environment initially promotes the removal of the repressive histone mark H3K27me3 at theWUSlocus in a cell cycle-dependent manner. Subsequently, the B-type ARABIDOPSIS RESPONSE REGULATORs (ARRs) ARR1, ARR2, ARR10, and ARR12, which function as transcriptional activators in the cytokinin signaling pathway, spatially activateWUSexpression through binding with microRNA165/6-targeted HD-ZIP III transcription factors. Thus, our results provide important insights into the molecular framework for cytokinin-directed shoot regeneration and reveal a two-step mechanism for de novo activation ofWUS.
authors.affiliation: National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology (SIPPE), Shanghai 200032, P.R. China.|University of Chinese Academy of Sciences, Shanghai 200032, P.R. China.
authors.forename: Tian-Qi
authors.identifier: http://orcid.org/0000-0001-8000-4770
authors.initials: TQ
authors.lastname: Zhang
authors.affiliation: National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology (SIPPE), Shanghai 200032, P.R. China.
authors.forename: Heng
authors.identifier: http://orcid.org/0000-0003-0522-7290
authors.initials: H
authors.lastname: Lian
authors.affiliation: National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology (SIPPE), Shanghai 200032, P.R. China.
authors.forename: Chuan-Miao
authors.initials: CM
authors.lastname: Zhou
authors.affiliation: National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology (SIPPE), Shanghai 200032, P.R. China.
authors.forename: Lin
authors.identifier: http://orcid.org/0000-0003-4718-1286
authors.initials: L
authors.lastname: Xu
authors.affiliation: State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, P.R. China.|National Center for Plant Gene Research, Beijing 100101, P.R. China.
authors.forename: Yuling
authors.identifier: http://orcid.org/0000-0002-1189-1676
authors.initials: Y
authors.lastname: Jiao
authors.affiliation: National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology (SIPPE), Shanghai 200032, P.R. China jwwang@sibs.ac.cn.|ShanghaiTech University, Shanghai 200031, P.R. China.
authors.forename: Jia-Wei
authors.identifier: http://orcid.org/0000-0003-3885-6296
authors.initials: JW
authors.lastname: Wang
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism* / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D018506:Gene Expression Regulation, Plant / Q000235:genetics / Q000502:physiology; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism*; D018520:Plant Shoots / Q000235:genetics / Q000378:metabolism* / Q000502:physiology*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
chemical_list: C117138:ARR1 protein, Arabidopsis; C469257:ARR10 protein, Arabidopsis; C519632:ARR12 protein, Arabidopsis; C117139:ARR2 protein, Arabidopsis; D029681:Arabidopsis Proteins; D004268:DNA-Binding Proteins; D018398:Homeodomain Proteins; D014157:Transcription Factors; C116421:WUSCHEL protein, Arabidopsis