Figure 1.

Sequence alignment of the C termini of Dd-PDI and other ER proteins. The recently described PDI-D domain is ∼100 residues long (Ferrari and Söling, 1999), and the highest conservation is found in the C-terminal half. Identical residues are highlighted in dark gray, homologies in light gray. The KDEL-type retrieval signal is boxed. PDI57 and PDI13 represent the fragments used to construct GFP chimeras (see text). The two asterisks indicate the positions of mutations in the Drosophila windbeutel gene. The species of origin and accession numbers for these sequences are as follows. PDI-Dα subfamily: DdPDI: D. discoideum, AF019112; alfPDI: Medicago sativa, P38661; aspPDI: Aspergilus nidulans, Q00216; SpPDI: PDI2, S. pombe, O13811; AtPDI: Arabidopsis thaliana, O22263; TabPDI: Nicotiana tabacum, P93358. PDI-Dβ subfamily: Erp28: Homo sapiens Erp28, X94910; ER29: Rattus norvegicus, P52555; Wind: Drosophila melanogaster windbeutel, O44342; ScMPD2: S. cerevisiae, D34634. Other: ScERO1: ER oxidative protein, S. cerevisiae, z50178.