title: Coordination of Meristem Doming and the Floral Transition by Late Termination, a Kelch Repeat Protein.
abstract: Enlargement and doming of the shoot apical meristem (SAM) is a hallmark of the transition from vegetative growth to flowering. While this change is widespread, its role in the flowering process is unknown. Thelate termination(ltm) tomato (Solanum lycopersicum) mutant shows severely delayed flowering and precocious doming of the vegetative SAMLTMencodes a kelch domain-containing protein, with no link to known meristem maintenance or flowering time pathways. LTM interacts with the TOPLESS corepressor and with several transcription factors that can provide specificity for its functions. A subgroup of flowering-associated genes is precociously upregulated in vegetative stages ofltmSAMs, among them, the antiflorigen geneSELF PRUNING(SP). A mutation inSPrestored the structure of vegetative SAMs inltm spdouble mutants, and late flowering was partially suppressed, suggesting that LTM functions to suppressSPin the vegetative SAM In agreement,SP-overexpressing wild-type plants exhibited precocious doming of vegetative SAMs combined with late flowering, as found inltmplants. Strong flowering signals can result in termination of the SAM, usually by its differentiation into a flower. We propose that activation of a floral antagonist that promotes SAM growth in concert with floral transition protects it from such terminating effects.
authors.affiliation: Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot 76100, Israel.
authors.forename: Lior
authors.initials: L
authors.lastname: Tal
authors.affiliation: The Nancy and Stephen Grand Israel National Center for Personalized Medicine, Weizmann Institute of Science, Rehovot 76100, Israel.
authors.forename: Gilgi
authors.identifier: http://orcid.org/0000-0001-8513-1998
authors.initials: G
authors.lastname: Friedlander
authors.affiliation: Israel Structural Proteomics Centre, Weizmann Institute of Science, Rehovot 76100, Israel.
authors.forename: Netta Segal
authors.initials: NS
authors.lastname: Gilboa
authors.affiliation: Israel Structural Proteomics Centre, Weizmann Institute of Science, Rehovot 76100, Israel.
authors.forename: Tamar
authors.initials: T
authors.lastname: Unger
authors.affiliation: The Nancy and Stephen Grand Israel National Center for Personalized Medicine, Weizmann Institute of Science, Rehovot 76100, Israel.
authors.forename: Shlomit
authors.identifier: http://orcid.org/0000-0001-5103-1649
authors.initials: S
authors.lastname: Gilad
authors.affiliation: Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot 76100, Israel yuval.eshed@weizmann.ac.il.
authors.forename: Yuval
authors.identifier: http://orcid.org/0000-0001-8290-0018
authors.initials: Y
authors.lastname: Eshed
mesh_terms: D035264:Flowers / Q000166:cytology* / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D018506:Gene Expression Regulation, Plant; D000071776:Kelch Repeat / Q000235:genetics / Q000502:physiology*; D018551:Solanum lycopersicum / Q000166:cytology* / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D018519:Meristem / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D009154:Mutation; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
chemical_list: D010940:Plant Proteins; D014157:Transcription Factors