ISPD produces CDP-ribitol used by FKTN and FKRP to transfer ribitol-phosphate onto α-dystroglycan

Mutations in genes required for the glycosylation of α-dystroglycan lead to dystroglycanopathies. Here, the authors show that three of these enzymes (ISPD, FKTN and FKRP) work together to attach ribitol phosphate to α-dystroglycan.