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Title: Mechanism of fertilization-induced auxin synthesis in the endosperm for seed and fruit development

The dominance of flowering plants on earth is owed largely to the evolution of maternal tissues such as fruit and seedcoat that protect and disseminate the seeds. The mechanism of how fertilization triggers the development of these specialized maternal tissues is not well understood. A key event is the induction of auxin synthesis in the endosperm, and the mobile auxin subsequently stimulates seedcoat and fruit development. However, the regulatory mechanism of auxin synthesis in the endosperm remains unknown. Here, we show that a type I MADS box geneAGL62is required for the activation of auxin synthesis in the endosperm in bothFragaria vesca, a diploid strawberry, and in Arabidopsis. Several strawberryFveATHBgenes were identified as downstream targets ofFveAGL62and act to repress auxin biosynthesis. In this work, we identify a key mechanism for auxin induction to mediate fertilization success, a finding broadly relevant to flowering plants.

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Publication Date:
Journal Name:
Nature Communications
Nature Publishing Group
Sponsoring Org:
National Science Foundation
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