Simu gene is important for maintaining dead cell clear-up in the developing fly embryo
When it comes to building a fruit fly embryo, death is just as important as life. Throughout development, certain cells are programmed to die in the right place and at the right time through a process called apoptosis, which sculpts the tissues of the embryo. In order to prevent a pileup of cellular corpses, special immune cells known as macrophages (grey blobs, top) patrol the embryo, eating up dead cells as they go. These macrophages wander freely in normal embryos (left), revealed by the coloured traces. But in embryos lacking a gene called Simu (right), their journeys are severely curtailed. The same processes of apoptosis and cell clearance are also at work in humans, from the very earliest days in the womb through adulthood, and many of the molecules are the same. So these wandering fruit fly cells could have important lessons to teach us about life, death and development.
Written by Kat Arney
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