Starting from a single point at conception, the human body ends up containing ten times as many cells as there are stars in the Milky Way. This biological ‘Big Bang’ is guided by genes – the codes that are responsible for specific physical traits that make us who we are. When it’s time for a certain type of cell to bloom, protein messengers nudge the right genes into action. One of these messengers, called Yorkie, is instrumental in initiating a wide range of tissue growth. Pictured is a close-up of a fruit fly embryo – the site where a wing will emerge. Without Yorkie, the genes that should be buzzing with activity as this fledgling wing develops are silent (inactivity represented by red areas). While helping to shed light on the intricate processes that mediate tissue growth, understanding Yorkie could have far-reaching consequences due to its role in tumour development.
Written by Jan Piotrowski
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