Figure 3.

Phosphorylation of novel carbohydrates. Cell lines stably expressing wild type (proCL) or mutants containing only the novel glycosylation sites at Asn-138 (N1Q3) or Asn-175 (N2Q3). Cells were radiolabeled for 4–5 h with either [³⁵S]methionine (S) or [³²P]orthophosphate (P). Cell lysates were subjected to immunoprecipitation and SDS-PAGE, as previously, and processed for fluorography or autoradiography, respectively. The proenzymes (pro) and the processed, single-chain proteins (mature) are indicated. The position of the 29-kDa size standard is shown on the left and lane numbers are provided on the bottom.