Just as cities are full of buses – shuttling people around to school, work, play or home – our cells are bustling with tiny transporters that do a similar job. These fluffy-looking balls are zebrafish eggs, stained with a fluorescent dye that reveals these blobby biological buses, known as vesicles, packed with molecules rather than passengers. But there's a key difference between them – the one on the left is normal, while the one on the right is missing a gene called souffle (also known as spastizin), so the vesicles don't form properly. Children born with a faulty version of souffle have a condition known as hereditary spastic paraplegia, where they gradually lose the use of their legs. By understanding how souffle works in model systems like these fish eggs, researchers can start to figure out what's going wrong in the human disease and search for future treatments.
Written by Kat Arney
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