How cells get rid of their waste: long-sought-after sulphate transporter identified

In order to stay healthy, cells must break down waste products and remove their components. Researchers from Jülich, Hanover and Dresden have identified a protein that plays a key role in this process – a role that had previously remained unclear. Surprisingly, the protein also has a second function.

Mehrere schematische Darstellungen von Zellen mit verschiedenen farbigen Kugeln und einer Membran mit Kanälen und Transportmechanismen. (Mistral: Mistral Medium 3.5, 2026-09-10)

Cells have a sophisticated system for disposing of waste: they break down foreign substances and recycle the cell’s own material that has reached the end of its useful life. If this process malfunctions, breakdown products can accumulate and lead to serious diseases. Lysosomes play a central role in waste recycling: they are tiny cellular components that break down large molecules and subsequently make their constituents available again. Researchers from Jülich, Hannover Medical School and the Max Planck Institute for Molecular Cell Biology and Genetics in Dresden have now answered an unresolved question about this process: how does sulphate, a degradation by-product, leave the lysosome?

They have identified a specific protein predominantly found in the brain and kidneys – SLC26A11 – as the transporter. The protein is capable of transporting sulphate out of the lysosomes. A corresponding transport pathway was observed decades ago – but the responsible protein remained unknown.

This transport is important because, otherwise, sulphate could accumulate within the lysosome and inhibit enzymes involved in waste disposal. The undesirable accumulation of sulphate can lead to so-called lysosomal storage disorders, such as Sanfilippo syndrome, a fatal neurological disease. Identifying of SLC26A11 provides a starting point for investigating the molecular processes underlying these disorders in greater detail.

Surprisingly, SLC26A11 can perform two functions. As well as acting as a transport protein, it can also form a channel through which chloride ions can flow in and out of cells. This regulates the electrolyte levels within the cells and their surroundings.

The second function of SLC26A11 could also be medically relevant. Under highly acidic conditions, such as those that can occur when there is a lack of oxygen in brain tissue, this channel activity could contribute to nerve cell swelling – for example, leading to fluid retention in the brain, known as cerebral oedema. These findings therefore open up long-term prospects for both research into lysosomal storage disorders and new strategies to combat cerebral oedema.

Original publication

Kuhn, B.T., Kovermann, P., Haddad, B.G., et al., SLC26A11 is an atypical solute carrier with dual transport-channel function mediating lysosomal sulfate transport. Nature Communications 17, 7407 (2026). https://doi.org/10.1038/s41467-026-75749-4