Fig. 4.

(A) Alignment of predicted protein sequence of transcripts containing a recombined VHδ gene isolated from platypus spleen RNA. The individual clones are identified by the last three digits of their GenBank accession numbers (JQ664690–JQ664710). Shown is the region from FR3 of the VHδ through the beginning of the Cδ domain. The sequence in bold at the top of the alignment is the germ-line VHδ and Cδ gene sequence. The double cysteines at the end of FR3 and unpaired cysteines in CDR3 are shaded, as is the canonical FGXG in FR4. (B) Nucleotide sequence of the CDR3 region of the eleven unique V(D)J recombinants using VHδ described in the text. The germ-line sequence of the 3′-end of VHδ, the two Dδ, are shown at the top. The germ-line Jδ sequences are shown on the right-hand side of the alignment interspersed amongst the cDNA sequences using each. Nucleotides in the junctions between the V, D, and J segments, shown italicized, are most likely N-nucleotides added by TdT.