Embryo development

All multicellular organisms develop from a single cell, the zygote. We are interested in understanding how different cell types arranged in the correct body plan arise from the zygote. For this purpose we have identified genes that instruct cell groups of different destiny and set up body axes during earliest embryo development. We are using molecular, functional genomic, and live imaging methods to analyze the mechanisms that specify early embryo cells and that arrange them into the embryo body. Previously, our work revealed that a cascade of WOX homeodomain transcription factors regulates the successive initiation of embryo domains (Haecker et al, 2004, Breuninger et al. 2008). Our recent work addresses how polarity of the zygote is regulated by the WRKY2 transcription factor (Ueda et al., 2011). The activity of WRKY2 shows that in contrast to animal model system, in Arabidopsis, early pattern information requires trancription in the zgyote and does not rely etirley on stored maternal products.

Embryo development of Arabidopsis thaliana:

The development of embryo regions and seedling organs can be followed from earliest stages on due to a largely invariant cell division pattern (for a review on plant embryo development see: Laux and Jürgens, 1997).

Our selected publications on embryo development:

Ueda, M. and Laux,T. (2012). The origin of the plant body axis. Curr. Op. Plant Biol. 15, 578-584.

Ueda, M., Zhang, Z., and Laux, T. (2011). Transcriptional activation of Arabidopsis axis patterning genes WOX8/9 links zygote polarity to embryo development. Developmental Cell, 20, 264-270.

Zhang, Z. and Laux, T. (2011). The asymmetric division of the Arabidopsis zygote: from cell polarity to an embryo axis. Sex. Plant Reprod. 24, 161-9.

Mallory et al (2009). Redundant and specific  roles of the ARGONAUTE (AGO) proteins AGO1 and ZLL in development and small RNA-directed gene silencing. PLoS Genet. 5, e1000646.

Breuninger et al (2008). Differential expression of WOX genes mediates apical-basal axis formation in the Arabidopsis embryo. Dev Cell 14, 867-876.

Tucker et al (2008). Vascular signalling mediated by ZWILLE potentiates WUSCHEL function during shoot meristem stem cell development in the Arabidopsis embryo. Development. 17, 2839-2843.

Haecker et al  (2004). Expression dynamics of WOX genes mark cell fates decisions in early Arabidopsis embryonic patterning. Development 131, 657-668.

Laux et al (2004) Genetic regulation of embryonic pattern formation. Plant Cell 16, S190-202.