Sperm are keen swimmers, making them efficient delivery vehicles for genetic material. Their classic form, preserved from flies to man, appears during maturation when a process removes all unnecessary cell contents leaving only the DNA at the head (shown in blue) and the machinery for moving the tail (dyed red). This process normally kills other cell types so how sperm survive this step is a conundrum.To unravel the problem researchers sought out infertile male fruit flies and identified mutations responsible for their sterility. They found three proteins (shown in yellow) which jointly allow the cell death process to operate. Since the proteins are only present in those areas that are not needed, essential cell parts remain intact. In humans, the same three proteins are surprisingly similar to their fruit fly counterparts and two are implicated in infertility. Studying the humble fruit fly is helping progress human fertility research.
Written by Julie Webb
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