Figure 3. Reduced CDP-pentitol levels and α-dystroglycan glycosylation in ISPD KO cells can be corrected by a bacterial CDP-ribitol pyrophosphorylase.

(a) HPLC analysis of WT HAP1 cells and of two ISPD KO clones that have been complemented or not with mouse ISPD. The arrow indicates the expected retention time for CDP-ribitol. (b–d) Assessment of α-dystroglycan glycosylation by flow cytometry using antibody IIH6 in wild-type cells and one ISPD KO clone, in which mouse ISPD (b) or Streptococcus pneumonia tarI (d) was expressed. The N-terminal part of ISPD shares similarity with S. pneumoniae tarI, a CDP-ribitol pyrophosphorylase (c). Additional ISPD KO clones are shown in Supplementary Fig. 4. (e) Laminin overlay analysis was performed in wild-type cells and two ISPD knockout clones completemented or not with S. pneumoniae tarI. Western blot analysis for β-dystroglycan is shown as loading control.