MAAP · Multidimensional Analysis of Axis Patterning in Plant Embryo
Horizon 2020 — Marie Skłodowska-Curie Actions
- Duration
- 2017-08-01 → 2019-07-31
- EU contribution
- €159,461
- Participants
- 1
- Scheme
- MSCA-IF-EF-ST
Lines connect the coordinator with its partners.
Results in brief
Multidimensional Analysis of Axis Patterning in Plant Embryo
Understanding the mechanisms of morphogenesis is a fundamental challenge in biology. Embryogenesis encompasses the earliest stages of tissue morphogenesis in plants. Therefore it presents good opportunities to address this challenge. During embryogenesis, the shape of the embryo changes from radial/spherical to bilateral/heart-shaped and at the culmination of embryogenesis body axes and the root and shoot meristems are established. Unlike animal cells, plant cells are surrounded by stiff cell walls and as such are immobile. Thus positional information has an important role in regulating development of form. How does positional information guide axes formation? In previous studies the host group, showed that tight regulation of the homeobox proteins; PHABULOSA (PHB) and PHAVOLUTA (PHV) is important for apical basal and central peripheral axes formation during embryogenesis. However how this happens is unknown. The embryo is simple and it consists of a limited numbers of cells providing a good platform to study this problem and understand how differential cell growth mediates PHB/PHV-dependent axes delimitation. However, because the embryo is contained inside the ovule, and it is of small size therefore cannot easily manipulate and study how gene action influences growth. The objective of this project was to establish a 4D time-lapse system of embryogenesis, and to perform cellular-level quantitative analysis of growth, cell division, and gene expression to understand the morphogenesis of embryos. We have optimized the image acquisition and image processing methods and succeeded in preforming 4D time-lapse imaging of embryogenesis for the first time. We have also established other new protocols to observe morphology of embryo in detail and we are now generating a 4D growth map of embryo. Thus, the project has contributed significantly to the field of plant embryology and we have generated a wealth of tools that will be broadly relevant for the field of plant development.
Data: CORDIS, © European Union
Project objective
Plant cells are immobile, therefore positional signaling is essential for body patterning. While many genes involved in positional signaling in plants are known, we currently lack a mechanistic understanding of their functions. Embryonic axis pattering is the earliest and simplest instances of positional signaling. In Arabidopsis thaliana, embryo is initially radial symmetry. Soon after, the embryo switches to bilateral symmetry and development continues along the newly-established axis. How these patterns emerge from a small group of homogeneous cells remains a fundamental unanswered question in developmental biology. Answering this question requires an in-depth analysis of the spatio-temporal relationship between gene expression and cellular patterns. Today, advanced microscopy and latest image analysis allow us to quantify division, growth and gene expression in individual cells throughout embryogenesis. The host group has been studying the regulatory role of homeobox proteins, PHABULOSA (PHB) and PHAVOLUTA (PHV). Distribution of PHB/PHV protein is restricted by microRNA to apical embryo, triggering embryonic shoot formation. If the PHB/PHV distribution is a positional signal reflecting apical-basal axis, how do they regulate cellular growth and division patterns to establish axis? I will generate a 4D map of axis patterning, extract high quality quantitative data to develop spatial computer models, and examine the interplay between geometry and genetic regulation on axis patterning. I will also apply same approaches to study embryos in other Brassicaceae species. Such comparative developmental analysis will reveal the core mechanism of axis formation shared among these species and also provide insights into the origins of their embryonic morphological diversity.
Original text from CORDIS.
Participants
- MAX-PLANCK-GESELLSCHAFT ZUR FORDERUNG DER WISSENSCHAFTEN EV · MUNCHENCoordinatorGermany
Links
Data: CORDIS, © European Union