Convergent expansion

The convergent extension is a Zellumordnung in a multicellular organism , the cells in such a way to reorder in, the cell layer that is narrowed and simultaneously extended. This is achieved by reorganizing the cytoskeleton , with arrays of microfilaments pulling the apical end of the respective cell together so that the cells become wedge-shaped and can then slide into one another (converge). When many cells converge in this way, it can cause significant enlargement of a layer of tissue. This process is probably triggered and controlled by the extracellular matrix , a network of secreted glycoproteins that plays an important role in the morphogenetic movements of cells.

Convergent expansion is relevant in the early stages of embryonic development ; it occurs, for example, with intussusception of the gastrula and with the elongation of the primitive intestine ( archenteron ).

literature

Neil A. Campbell, Jane B. Reece, Jürgen Markl (Eds.): Biology. 6th updated edition, Pearson, 2006, ISBN 978-3-8273-7180-5 , p. 1212.