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Travelling by Taxis

Trypanosome parasites travel through their fly host by sensing the environmental pH created by their neighbours

12 March 2022

Travelling by Taxis

Moving in spiralling colonies, young trypanosomes like these can cause fatal sleeping sickness – each wavy tendril is a separate parasite. They develop on a gruesome journey – hiding in mouthfuls of blood sucked into a fly’s gut, they spread through their new airborne home. Later they make a dash for the fly’s salivary glands ready to jump to a new – potentially human – host. Here researchers investigate early procyclic [a life stage] trypanosomes (highlighted in red and green), finding they travel through the fly by reacting to chemical signals produced by their neighbours. Mimicking this natural chemotaxis, these trypanosomes reach out towards unseen alkaline blobs placed on either side of the colony (middle column) but shy away from acid blobs (right). Researchers gain clues to how the parasite’s metabolism guides these acidic cues, and how they might block these vital steps in the spread of disease.

Written by John Ankers

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