Fig. 4. The WE motif in CT functions as a signal sufficient for lysosomal sorting in HeLa cells. (A) Structure, sequence and cross-species conservation of the LAMP/CT2 construct, carrying the 25 N-terminal amino acids of CT, and of its deletion and mutagenesis variants. N-term, N-terminus of rat LAMP1; TM, transmembrane domain of rat LAMP1; these were fused with the CT of OA1. (B) Immunofluorescence analysis of HeLa cells transiently transfected with expression vectors for LAMP/CT chimeras and processed as in Fig. 3B. In the merge, areas of colocalization can be observed in yellow/orange. LAMP/CT2M11 behaves as LAMP/CT2M5 WEAA (not shown). LAMP/CTCT2 is a LAMP/OA1 chimera carrying the 65 C-terminal amino acids of CT. Bar, 10 µm.