title: LACHESIS restricts gametic cell fate in the female gametophyte of Arabidopsis.
abstract: In flowering plants, the egg and sperm cells form within haploid gametophytes. The female gametophyte of Arabidopsis consists of two gametic cells, the egg cell and the central cell, which are flanked by five accessory cells. Both gametic and accessory cells are vital for fertilization; however, the mechanisms that underlie the formation of accessory versus gametic cell fate are unknown. In a screen for regulators of egg cell fate, we isolated the lachesis (lis) mutant which forms supernumerary egg cells. In lis mutants, accessory cells differentiate gametic cell fate, indicating that LIS is involved in a mechanism that prevents accessory cells from adopting gametic cell fate. The temporal and spatial pattern of LIS expression suggests that this mechanism is generated in gametic cells. LIS is homologous to the yeast splicing factor PRP4, indicating that components of the splice apparatus participate in cell fate decisions.
authors.affiliation: Institute of Plant Biology and Zürich-Basel Plant Science Center, University of Zürich, Zürich, Switzerland. rita.gross-hardt@zmbp.uni-tuebingen.de
authors.forename: Rita
authors.initials: R
authors.lastname: Gross-Hardt
authors.forename: Christina
authors.initials: C
authors.lastname: Kägi
authors.forename: Nadine
authors.initials: N
authors.lastname: Baumann
authors.forename: James M
authors.initials: JM
authors.lastname: Moore
authors.forename: Ramamurthy
authors.initials: R
authors.lastname: Baskar
authors.forename: Wendy B
authors.initials: WB
authors.lastname: Gagliano
authors.forename: Gerd
authors.initials: G
authors.lastname: Jürgens
authors.forename: Ueli
authors.initials: U
authors.lastname: Grossniklaus
mesh_terms: D017360:Arabidopsis / Q000166:cytology*; D001483:Base Sequence; D019070:Cell Lineage; D017931:DNA Primers; D005854:Germ Cells / Q000166:cytology*; D016133:Polymerase Chain Reaction
chemical_list: D017931:DNA Primers