The morphological variation among reproductive organs of extant seed plants makes assessment of organ homology difficult. Comparisons of expression patterns of homeotic genes that control organ development will yield new information about the homology of organs to assess inferences deduced from previous morphological studies. In angiosperms, the FLORICAULA/LEAFY (FLO/LFY) genes convert a vegetative shoot meristem to a floral meristem by inducing floral homeotic genes, most of which belong to the MADS‐box gene family. To provide insights into the evolution of reproductive organs in seed plants, a FLO/LFY homologue (GpLFY) was cloned from Gnetum parvifolium. GpLFY mRNA was expressed in both the vegetative shoot apex and the female strobilus. The GpLFY mRNA signal was detected in early developmental stages of the collar and the ovule primordium, including the nucellus and three envelopes. A comparison of FLO/LFY gene expression in Gnetum and the conifer Pinus radiata indicates that the Gnetum collar and ovul...
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