Projections called cytonemes grow out from cells and deliver molecules to developing tissue
Couriers will often try three times to deliver our parcels, but cells in tissues and organs can’t afford to wait. They’re constantly exchanging chemical signals – proteins produced in one cell are 'sent' to neighbouring cells, but how the delivery happens can be a little mysterious. In these zebrafish cells (artificially coloured red), Wnt proteins (green) help to coordinate development. They travel towards neighbouring cells down long arm-like projections called cytonemes. This cellular courier service is organised by the Wnt proteins themselves, which trigger the growth of the cytonemes. Disruption to this plan leads to delayed messages and serious problems in developing tissues. Researchers have found similar delivery networks at play in embryos and tumours, and understanding the proteins involved could help to deliver (or destroy) these vital messages.
Written by John Ankers
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