Figure 4.

Multiple sequence alignments of the core I and II proteins and the MPP subunits from various sources. The accession number for each sequence is shown on the right-hand side. The C. reinhardtii sequences were derived from the EST clones indicated in the text. A, Comparison of C. reinhardtii core I with other core I and beta-MPP amino acid sequences. C. reinhardtii core I exhibits the consensus sequence usually found for beta-MPP protease activity, including the zinc-binding motif (H-X-X-E-H) that is absent in the mammalian core I sequences. B, Alignment of core II and alpha-MPP amino acid sequences. The core II sequence of C. reinhardtii lacks the consensus sequence (G-G-G-G-S-F-S-A-G-G-P-G-K-G-M/S-R-L-Y) believed to be required for alpha-MPP activity.