Figure 2.

Molecular nature of the TPS02 and TPS03 alleles in accessions Col-0 and Ws. A, Schematic representation of the structures of TPS02 and TPS03. Exons are represented by the gray boxes, and flanking regions and introns are represented by the lines between boxes. B, Alignment of nucleotide and amino acid sequence regions of the TPS02 (left) and TPS03 (right) alleles from accessions Col-0 and Ws indicating frame shift mutations caused by base pair insertions in the Col-0 TPS02 and Ws TPS03 genes. The white box marks premature stop codons. The gene-specific positions of the sequences are indicated. C, Amino acid sequence alignment of the full-length and truncated proteins of the Col-0 and Ws TPS02 and TPS03 alleles. Amino acids shaded in black are conserved in all sequences, and gray shading indicates amino acids conserved in two or three sequences. Dashes indicate gaps inserted for optimal alignment. Horizontal lines mark the highly conserved DDXXD, RXR, and RRX₈W motifs. A motif similar to the H-α1 loop region of apple MdAFS1 is marked by a thick dashed line. The asterisk indicates the putative cleavage site for a 25-amino acid plastidial transit peptide of the TPS02 protein.