Fig. 2. sel-2 sequence analysis. (A) Comparison of SEL-2 with mammalian neurobeachin and LRBA. The % amino acid identity is indicated for the BEACH and WD40 domains, and for other regions of high homology designated `A', `B' and `C' (aa 164-1036, 1059-1306, and 1407-1828 in SEL-2, respectively). Region C includes the predicted PH domain of neurobeachin and LRBA (see text). We note that neurobeachin and DAKAP550 have been shown to bind to the regulatory domain (RII) of PKA with high affinity in vitro (Han et al., 1997; Wang et al., 2000b), whereas LRBA does not (Wang et al., 2000b). The RII-binding region of neurobeachin lies in the unconserved interval between homology regions A and B. (B) Phylogenetic bootstrap tree constructed from an alignment of the C-terminal regions (see Materials and methods) of C. elegans (C.e.) SEL-2, VTB23.5 and T01H10.8 and their homologs. Numbers at the nodes are bootstrap values, indicating the frequency of occurrence of a given partition in the 100 replicate trees. Boxed areas represent subfamilies of BEACH domain-containing proteins. Species are designated as follows: D.m., Drosophila melanogaster; H.s., Homo sapiens; M.m., Mus musculus; D.d., Dictyostelium discoideum.