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Tissue elongation is part of the repertoire of processes that allow an organ to acquire its shape (morphogenesis). In the last years, the elongation of the ovarian follicle of Drosophila has emerged as a model of choice for the study of tissue elongation mechanisms. During its development the initially spherical follicle becomes ovoid and this elongation is controlled by the epithelial cells surrounding each follicle. However, so far, all studies on the subject have focused on the basal domain of these cells.
In its last study (Alegot et al.,) , the group of Vincent Mirouse has shown that the apical domain of the epithelial cells also contributed to this elongation.
This study answers the three main questions that can be asked when we study a mechanism of elongation, namely: what is the signal orienting the elongation, what is the mechanical force generating this elongation, and what are the cell behaviors associated with this elongation. They found that a JAK-STAT signaling gradient (signal) induces apical pulses at the poles (force), which cause cell constrictions and intercalations (behaviors), increasing curvature at the poles and thereby causing follicle elongation.
This work is published in eLIFE (Alegot et al., 2018).
Last modified: 02/07/2019