title: LATE MERISTEM IDENTITY2 acts together with LEAFY to activate APETALA1.
abstract: The switch from producing vegetative structures (branches and leaves) to producing reproductive structures (flowers) is a crucial developmental transition that significantly affects the reproductive success of flowering plants. In Arabidopsis, this transition is in large part controlled by the meristem identity regulator LEAFY (LFY). The molecular mechanisms by which LFY orchestrates a precise and robust switch to flower formation is not well understood. Here, we show that the direct LFY target LATE MERISTEM IDENTITY2 (LMI2) has a role in the meristem identity transition. Like LFY, LMI2 activates AP1 directly; moreover, LMI2 and LFY interact physically. LFY, LMI2 and AP1 are connected in a feed-forward and positive feedback loop network. We propose that these intricate regulatory interactions not only direct the precision of this crucial developmental transition in rapidly changing environmental conditions, but also contribute to its robustness and irreversibility.
authors.affiliation: Department of Biology, University of Pennsylvania, School of Arts and Sciences, Philadelphia, PA 19104, USA.
authors.forename: Jennifer J
authors.initials: JJ
authors.lastname: Pastore
authors.forename: Andrea
authors.initials: A
authors.lastname: Limpuangthip
authors.forename: Nobutoshi
authors.initials: N
authors.lastname: Yamaguchi
authors.forename: Miin-Feng
authors.initials: MF
authors.lastname: Wu
authors.forename: Yi
authors.initials: Y
authors.lastname: Sang
authors.forename: Soon-Ki
authors.initials: SK
authors.lastname: Han
authors.forename: Lauren
authors.initials: L
authors.lastname: Malaspina
authors.forename: Natasha
authors.initials: N
authors.lastname: Chavdaroff
authors.forename: Ayako
authors.initials: A
authors.lastname: Yamaguchi
authors.forename: Doris
authors.initials: D
authors.lastname: Wagner
mesh_terms: D017360:Arabidopsis / Q000033:anatomy & histology / Q000235:genetics / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D025461:Feedback, Physiological; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D026161:MADS Domain Proteins / Q000235:genetics / Q000378:metabolism*; D018519:Meristem / Q000502:physiology; D015398:Signal Transduction / Q000502:physiology; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism*; D018808:Transcription Factor AP-1 / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D020798:Two-Hybrid System Techniques
chemical_list: C091535:AP1 protein, Arabidopsis; D029681:Arabidopsis Proteins; C074747:LFY protein, Arabidopsis; D026161:MADS Domain Proteins; D015534:Trans-Activators; D018808:Transcription Factor AP-1; D014157:Transcription Factors