Two examples of conserved exon–intron structure.

This diagram indicated that conserved exon–intron structure with conserved exon phases existed in kinase domain. Filled boxes: red represents Pkinase or Pkinase_Tyr domain; black boxes: untranslated regions (UTRs); white boxes: other exon regions; lines: introns. Numbers 0, 1, and 2: exon phases. The lengths of the boxes and lines are scaled based on the lengths of genes. The long introns are shorted by “//”. (A) non-RLK example: CAMK_CDPK. (B) RLK example: RLK_Pelle_LysM.