Interleukin-34 (IL-34) is highly expressed in brain. IL-34 signaling via its cognate receptor,
colony-stimulating factor-1 receptor (CSF-1R), is required for the development of microglia.
However, the differential expression of IL-34 and the CSF-1R in brain suggests that IL-34
may signal via an alternate receptor. By IL-34 affinity chromatography of solubilized mouse
brain membrane followed by mass spectrometric analysis, we identified receptor-type
protein-tyrosine phosphatase ζ (PTP-ζ), a cell surface chondroitin sulfate (CS) proteoglycan …