Feedback communication between mother plant and embryo regulating early embryo development in Arabidopsis thaliana

• Applicant: Professor Dr. Thomas Laux
• Subject Area: Plant Cell and Developmental Biology
• Term: from 2014 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 261399760

The asymmetric division of the zygote establishes the apical-basal (shoot-root) axis of the plant embryo by generating two daughter cells with different developmental programs: an apical embryonic cell and a basal precursor of the suspensor, which connects the embryo with the mother plant. Early embryo development is tightly coordinated with surrounding maternal tissues, but unlike in animals, little is known yet about maternal factors regulating early embryo patterning. During the first funding period, we discovered a yet unknown feedback communication between the mother plant and the embryo: Fertilization provides a signal to the maternal sporophytic integuments that surround the future embryo to trigger increased biosynthesis of the plant hormone auxin. This upregulation in turn is required to signal back to the embryo and to regulate early steps in body plan patterning. In addition to our published results, we have already obtained several exiting new data which form the basis for our studies during the second funding period, applied here for. One unexpected result, for example, is that the non-canonical IGA auxin biosynthesis pathway is involved in maternal signaling, in parallel to canonical auxin biosynthesis. During the second funding period, we will test specific hypothesis that originated from our work in the first funding period, together with performing a mutant screen and a novel single-cell sequencing to elucidate the molecular mechanisms of maternal and embryonic communication. In addition to providing insight into a fundamental question of plant development, the results of this project have the potential to contribute to improved regeneration strategies in plant breeding.

• DFG Programme: Research Grants