Fig. 3. Alignment of amino acid sequences of sea urchin NSF and Chinese hamster NSF. GenBank accession numbers: sea urchin NSF AF171096; Chinese hamster, X15652. An asterisk (*) underneath the sequences indicates amino acid identity, two dots (:) a conservative substitution and a single dot (.) a semi-conservative substitution. Residues in bold are putative nucleotide-binding motifs within each domain (Walker et al., 1982) at residues 264-271 and 547-554 of the sea urchin sequence. The underlined peptide sequence, which spans the D1-D2 domain boundary at residue 490 (Whiteheart et al., 1994), was used to generate polyclonal antibodies.