Alignment of genomic and cDNA sequences. The gDNAs were taken from the sequenced 26 S-18 S spacers and correspond mostly to 5 S rDNA1 present downstream of the 26 S gene . One gDNA clone (12_2) was derived from a 5 S rDNA2 variant harboring an internal deletion. Three sequences (S_4a-c) originated from a cloned 5 S-5 S trimer from A. tridentata. Note, four mutations in the S4_c monomer. The cDNA clones were obtained from amplifications using the 5SgF and 5SgR primers. Conserved regulatory elements are boxed.