Fig 2.

Genetic structure of the rf-PPR592 gene. (A) Comparison of Rf-PPR592 and rf-PPR592 reveals a size polymorphism. The first lane was loaded with the Rf-PPR592 PCR amplicon obtained from a restorer line (Rf/Rf), the adjacent lane was loaded with the rf-PPR592 PCR amplicon obtained with the same primer pair from a CMS line (rf/rf). (B) Comparison of Rf-PPR592, Rf-PPR591, and rf-PPR592 reveals five similarity blocks. For each block, (I to V), the two blocks that exhibit the greatest similarity are shown with the same shading. Overall all three sequences are greater than 90% identical at the nucleotide level except in block V, where Rf-PPR591 exhibits only 23% identity to the other two genes. The locations of 47- and 49-nt deletions in Rf-PPR591 and 47- and 530-nt deletions in rf-PPR592 with respect to the Rf-PPR592 sequence in blocks I and II are shown as lines.