Fig. 3. Golgi to chloroplast transport and protein import requires light and ATP. Isolated Euglena chloroplasts were incubated with a ³⁵S-labelled Golgi membrane fraction (M) with the indicated additions (+) and omissions (–) for 60 minutes. Fluorographs of [³⁵S]pLHCPII immunoprecipitated from Percoll-purified chloroplasts are shown. The amount of LHCPII and the 50 kDa partially processed pLHCPII polyprotein transported to and imported into isolated chloroplasts was reduced when ATP was omitted from the reaction or when the reaction was incubated in the dark indicating a requirement for an extra- and intrachloroplast source of ATP.