Summary of shape change and displacement of cells progressing through the morphogenetic furrow. Cells entering MF constrict both apically and basally and undergo intercalations at both apical and basal sides forming new junctions parallel to MF. Cells exiting the MF expand their apical area and undergo intercalation, forming new junctions perpendicular to MF. Basal area of non-photoreceptor cells (depicted here) expands. Within MF, apical cell side flows toward anterior. Cells entering and exiting MF form protrusions oriented preferentially toward the posterior that enable basal cell displacement toward posterior, leading to tilting of cells. See alsoFigure S7andVideo S13.
