XVI International Botanical Congess

Transcription factors encoded by the MADS, LFY and KNOX genes have important roles in plant development. We will present hypotheses on the relationship between the evolution of these transcription factors and plant body plan. MADS and LFY genes are involved in the reproductive organ development in angiosperms. Based on the gene trees and comparison of expression patterns in angiosperms, Ginkgo, Gnetum, conifers, Ceratopteris, Physcomitrella, and Chara, the increase of the number of MADS genes and subsequent diversification of expression patterns are likely to be related to the evolution of complex reproductive organs. Lower vascular plants have a single shoot apical cell, while seed plants have multicellular shoot apex. The analyses of KNOX genes in Arabidopsis and Ceratopteris suggest that the basic mechanism of shoot development is conserved between them.