MST43

The life cycle of higher plants is largely divided into three stages: embryogenesis, vegetative growth, and reproductive growth, and important vegetative organs are formed during embryogenesis. Therefore, embryogenesis is crucial for plant morphogenesis, and understanding the mechanisms of organogenesis in the embryo is of great significance for elucidating the overall picture of plant development. In the model plant Arabidopsis, the cell lineage during embryogenesis is clear and much information on gene expression related to organogenesis has been obtained. In contrast, in rice, an important global crop, the cell lineage during organogenesis is unclear, making it difficult to analyze the early stages of embryogenesis. Furthermore, there are many aspects of developmental pattern that is different from Arabidopsis, such as interactions with the endosperm during development and the presence of a dorsal-ventral axis. Therefore, morphological mutants with abnormal organ formation are powerful tools for elucidating the molecular mechanisms regulating embryogenesis in rice, and numerous mutants have been identified to date. In the present study, we identified segmented embryo (sem) mutant in which a single embryo is divided into multiple compartments (Figure 1A-B). sem forms shoots in each compartment, and multiple shoots germinate from a single seed (Figure 1C-D), but organ formation after germination is normal, suggesting that sem is an embryo development-specific mutant. In this presentation, we report on the morphological analysis of sem mutants and the identification of the causal gene, with the aim of elucidating the molecular mechanism by which SEM controls embryogenesis in rice.

References:

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