Forces directing germ-band extension in Drosophila embryos

• Published in: Mechanisms of development Vol. 144; no. Pt A; pp. 11 - 22
• Main Authors: Kong, Deqing, Wolf, Fred, Großhans, Jörg
• Format: Journal Article
• Language: English
• Published: Ireland Elsevier B.V 01.04.2017
• Subjects: Actins - genetics; Actins - metabolism; Animals; Biomechanical Phenomena; Body Patterning - genetics; Cadherins - genetics; Cadherins - metabolism; Calcium Signaling; Cell Division; Cell intercalation; Drosophila; Drosophila melanogaster - embryology; Drosophila melanogaster - genetics; Drosophila melanogaster - metabolism; Drosophila Proteins - genetics; Drosophila Proteins - metabolism; Embryo, Nonmammalian; Embryonic Development - genetics; Epidermal Cells; Epidermis - embryology; Epidermis - metabolism; Epithelial Cells - cytology; Epithelial Cells - metabolism; Forces; Gene Expression Regulation, Developmental; Germ-band extension; Models, Statistical; Cell intercalation; Germ-band extension; Forces; Drosophila
• ISSN: 0925-4773; 1872-6356; 1872-6356
• DOI: 10.1016/j.mod.2016.12.001

Body axis elongation by convergent extension is a conserved developmental process found in all metazoans. Drosophila embryonic germ-band extension is an important morphogenetic process during embryogenesis, by which the length of the germ-band is more than doubled along the anterior-posterior axis. This lengthening is achieved by typical convergent extension, i.e. narrowing the lateral epidermis along the dorsal-ventral axis and simultaneous extension along the anterior-posterior axis. Germ-band extension is largely driven by cell intercalation, whose directionality is determined by the planar polarity of the tissue and ultimately by the anterior-posterior patterning system. In addition, extrinsic tensile forces originating from the invaginating endoderm induce cell shape changes, which transiently contribute to germ-band extension. Here, we review recent progress in understanding of the role of mechanical forces in germ-band extension. •Germband extension in Drosophila embryos has served as a paradigm for body axis elongation.•Studies during the last decade have revealed mechanisms driving cell rearrangement.•Studies have revealed a central role of mechanical forces in germband extension.