Figure 4

mRNA in situ hybridization of EcAGO104 during sexual and apomictic reproduction in E. curvula. (a–d) Ovaries from the sexual genotype hybridized with an EcAGO104 antisense probe showing: (a) an ovule primordium with strong, patchy signal in the nucellus and integuments and no signal in the archesporial cell; (b) signal restricted to the functional megaspore in a tetrad; (c) a mature embryo sac with all cells positive and no signal in the surrounding nucellar cells, and; (d) a general view of reproductive organs. (e–h) Ovaries from the apomictic genotype hybridized with an EcAGO104 antisense probe showing: (e) an apomictic ovule primordium with a strong signal detected in the archesporial cell only; (f) an elongated, unreduced MMC; (g) a mature embryo sac, and; (h) a general view of reproductive organs. Arch: archespore, dm: degenerated megaspores, fm: functional megaspore, mes: mature embryo sac, emmc: elongated megaspore mother cell.