FIGURE 8.

Alignment of human UBL domain sequences harboring features similar to SF3A1-UBL. Sequences were aligned by ClustalW, and key features that were used as criteria for performing the search for UBL domains are indicated by boxes. These features include the amino-terminal extension, conserved tyrosine residues at or near position 772 and/or 773 relative to SF3A1, and carboxy-terminal lysine and/or arginine residues. UBL domains with a tyrosine or a conservative phenylalanine substitution at position analogous to 772 are highlighted in purple. UBL domains with a tyrosine at position analogous to 773 are highlighted in blue, and domains with sequences containing a conservative phenylalanine substitution at this position are highlighted in green. Domains that lack a conserved tyrosine/phenylalanine or the RGG motif, but contain carboxy-terminal lysine and/or arginine residues, are highlighted in yellow. Sequences of UBL domains containing a conserved tyrosine and the RGG motif are indicated by an asterisk. In the aligned sequences, a dot indicates the presence of an identical residue to reference (SF3A1-UBL) and a dash indicates a gap. The UniProt accession numbers for all proteins included in the alignment are listed in Supplemental Table S2.