Figure 3.

(A) Pulse–chase labeling of biosynthesized Menkes ATPase in HeLa cells. Cultures were pulsed for 10 min with [³⁵S]methionine and [³⁵S]cysteine at 500 μCi/ml and then chased for indicated times in media containing excess methionine and cysteine. Immunoprecipitates of cell lysates were analyzed by SDS/10% PAGE and fluorography. (B) HeLa cells were pulse-labeled for 10 min (lanes 1–3) followed by a 1-h chase (lanes 4–6). Cell lysates were immunoprecipitated with Menkes antibody and incubated without enzyme (lanes 1 and 4) or digested with endo H (lanes 2 and 5) or endo F (lanes 3 and 6).