title: The plant-specific protein FEHLSTART controls male meiotic entry, initializing meiotic synchronization in Arabidopsis.
abstract: Meiosis marks the transition from the sporophyte to the gametophyte generation in the life cycle of flowering plants, and creates genetic variations through homologous recombination. In most flowering plants, meiosis is highly synchronized within each anther, which is significant for efficient fertilization. To date, little is known about the molecular mechanisms of entry into meiosis and exit from it, and only a few genes in Arabidopsis have been characterized with a role in regulating meiotic progression. In this study, we report the functional characterization of a plant-specific basic helix-loop-helix (bHLH) protein, FEHLSTART (FST), a defect in which leads to premature meiotic entry and asynchronous meiosis, and results in decreased seed yield. Investigation of the time course of meiosis showed that the onset of leptotene, the first stage of prophase I, frequently occurred earlier in fst-1 than in the wild type. Asynchronous meiosis followed, which could manifest in the disruption of regular spindle structures and symmetric cell divisions in fst-1 mutants during the meiosis I/II transition. In accordance with frequently accelerated meiotic entry, whole-transcriptome analysis of fst-1 anthers undergoing meiosis revealed that 19 circadian rhythm genes were affected and 47 pollen-related genes were prematurely expressed at a higher level. Taken together, we propose that FST is required for normal meiotic entry and the establishment of meiotic synchrony.
authors.affiliation: Department of Horticultural Science, University of Minnesota, 1970 Folwell Avenue, St Paul, MN, 55108, USA.|College of Life Sciences, Henan Normal University, Xinxiang, Henan, 453007, China.
authors.forename: Junhua
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Horticultural Science, University of Minnesota, 1970 Folwell Avenue, St Paul, MN, 55108, USA.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Dukowic-Schulze
authors.affiliation: National Center for Genome Resources, 2935 Rodeo Park Drive E., Santa Fe, NM, 87505, USA.
authors.forename: Ingrid E
authors.initials: IE
authors.lastname: Lindquist
authors.affiliation: National Center for Genome Resources, 2935 Rodeo Park Drive E., Santa Fe, NM, 87505, USA.
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Farmer
authors.affiliation: Department of Horticultural Science, University of Minnesota, 1970 Folwell Avenue, St Paul, MN, 55108, USA.
authors.forename: Bridget
authors.initials: B
authors.lastname: Kelly
authors.affiliation: Department of Horticultural Science, University of Minnesota, 1970 Folwell Avenue, St Paul, MN, 55108, USA.
authors.forename: Tao
authors.initials: T
authors.lastname: Li
authors.affiliation: Department of Horticultural Science, University of Minnesota, 1970 Folwell Avenue, St Paul, MN, 55108, USA.
authors.forename: Alan G
authors.initials: AG
authors.lastname: Smith
authors.affiliation: National Center for Genome Resources, 2935 Rodeo Park Drive E., Santa Fe, NM, 87505, USA.
authors.forename: Ernest F
authors.initials: EF
authors.lastname: Retzel
authors.affiliation: National Center for Genome Resources, 2935 Rodeo Park Drive E., Santa Fe, NM, 87505, USA.
authors.forename: Joann
authors.initials: J
authors.lastname: Mudge
authors.affiliation: Department of Horticultural Science, University of Minnesota, 1970 Folwell Avenue, St Paul, MN, 55108, USA.
authors.forename: Changbin
authors.initials: C
authors.lastname: Chen
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D051792:Basic Helix-Loop-Helix Proteins / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D035264:Flowers / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D020869:Gene Expression Profiling / Q000379:methods*; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D008540:Meiosis / Q000235:genetics*; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D009154:Mutation; D010802:Phylogeny; D030821:Plants, Genetically Modified; D011058:Pollen / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid
chemical_list: D029681:Arabidopsis Proteins; D051792:Basic Helix-Loop-Helix Proteins; D049452:Green Fluorescent Proteins; C000612151:FEHLSTART protein, Arabidopsis
keywords: Arabidopsis thaliana; FEHLSTART; bHLH protein; meiosis; meiotic entry; synchrony