A group of white blood cells known as B cells, which play a key role in the human immune response, need a protein-targeting signal called mannose 6-phosphate (M6P) in order to proliferate, differentiate, and present immune cell-activating antigens, according to a study in The Journal of Cell Biology.
In a B cell from a mouse that mimics symptoms of mucolipidosis II patients, lysosomes are packed with undigested material.
Credit:Otomo et al., 2015
Mannose 6 phosphorylation of lysosomal enzymes controls B cell functions. Otomo, T. et al. 2015. J. Cell Biol. doi:10.1083/jcb.201407077