Section: New Results

Spatio-temporal registration of 3D microscopy image sequences of Arabidopsis floral meristems

Participants : Gaël Michelin, Grégoire Malandain.

This work is made in collaboration with Léo Guignard and Christophe Godin (Virtual Plants), within the Morphogenetics Inria Project Lab.

The shoot apical meristem (SAM) is at the origin of all the plant above-ground organs (including stems, leaves and flowers) and is a biological object of interest for the understanding of plant morphogenesis. The quantification of tissue growth at a cellular level requires the analysis of 3D microscopic image sequences of developing meristems. To address inter-individual variability, it is also required to compare individuals. This obviously implies the ability to process inter-individual registration, i.e. to compute spatial and temporal correspondences between sequences from different meristems.

In [8] , we propose a spatial registration method dedicated to microscopy floral meristem (FM) images, based on the registration of both the outer and the inner surfaces of the L1 layer (the epidermal cell layer). A given meristem (one timepoint) can be compared to a sequence (several timepoints) of an other meristem: the goodness-of-fit criterion allows to identify the best corresponding time-point in this sequence of an other individual, achieving the temporal registration (see figure 4 ). Since the morphological deformations remain important between successive images of a sequence, images interpolation between time-points is also performed in order to refine the sequence temporal resolution and thus to ensure a precise temporal registration.

Figure 4. Inter-individual temporal registration result with 3D views of the registered meristem and the interpolated movie at several time-points.