Transcriptional Regulation of Zygote Asymmetry in Arabidopsis thaliana
Final Report Abstract
This project investigates a central question in plant development: how is the plant's main body axis (root-shoot) established during embryo patterning? Preparing for the initial grant application, we demonstrated that the WRKY2 transcription factor is required to position the nucleus and thus the asymmetric zygotic division that separates the founder cells of the future embryo and the suspensor, which connects the embryo with the maternal tissues. During the first funding period, we revealed the transcriptional changes regulated during this process by WRKY2. We then discovered that the balance between transcriptional regulators of the apical and basal daughter cell fates in the zygote also control the asymmetric division by regulating the integrity of the actin cytoskeleton. As the next step, we looked at the events after the zygotic division. We discovered a WRKY2-dependent regulatory network in the basal daughter cell that controls basal development. One output of this network is the expression of the auxin efflux protein PIN7, which is required to pump auxin into the apical cell. As a response, the apical cell represses basal identity (including WRKY2), setting up a lateral inhibition mechanism that separates the developmental paths of the two zygotic daughter cells.
Publications
-
Transcriptional Activation of Arabidopsis Axis Patterning Genes WOX8/9 Links Zygote Polarity to Embryo Development. Developmental Cell, 20(2), 264-270.
Ueda, Minako; Zhang, Zhongjuan & Laux, Thomas
-
A Molecular Framework for the Embryonic Initiation of Shoot Meristem Stem Cells. Developmental Cell, 40(3), 264-277.e4.
Zhang, Zhongjuan; Tucker, Elise; Hermann, Marita & Laux, Thomas
-
Transcriptional integration of paternal and maternal factors in the Arabidopsis zygote. Genes & Development, 31(6), 617-627.
Ueda, Minako; Aichinger, Ernst; Gong, Wen; Groot, Edwin; Verstraeten, Inge; Vu, Lam Dai; De Smet, Ive; Higashiyama, Tetsuya; Umeda, Masaaki & Laux, Thomas
-
Maternal auxin supply contributes to early embryo patterning in Arabidopsis. Nature Plants, 4(8), 548-553.
Robert, Hélène S.; Park, Chulmin; Gutièrrez, Carla Loreto; Wójcikowska, Barbara; Pěnčík, Aleš; Novák, Ondřej; Chen, Junyi; Grunewald, Wim; Dresselhaus, Thomas; Friml, Jiří & Laux, Thomas
