Horizontal
transfer can be defined as the process by which genes can move between reproductively isolated species. National Center for Biotechnology Information
, Bethesda, Maryland, United States) searches using the full-length element from rice reveal that all other significant blast hits (e value <10−4) to Os493 that are not members of the genus Oryza are to sequences from maize, sorghum, or sugarcane, all of which, like Setaria, are Panicoid grasses of the tribe Andropogoneae. Sequencing of some products confirmed that they are highly similar to both the rice and the Setaria sequences. Despite the higher similarity of these sequences to those in Setaria, this analysis focused on a comparison between rice and Setaria because of the availability of the fully sequenced rice genome. Only the third intron of the mudrA gene and the third intron in the rice and Setaria is present in all three elements. maize was used as a proxy for Setaria because it is equally distant from rice as is Setaria, and, in contrast to Setaria, there are a very large number of genomic and cDNA sequences available in maize, making the identification of true orthologs relatively straightforward. If this region were subject to a reduced mutation frequency, we would expect to observe a low degree of variation when comparing intron or silent site sequences from the genes in rice with orthologs in maize.
More abstracts about the Horizontal Transfer of a Plant Transposon