Clustered and dispersed chromosomal distribution of the two classes of Revolver transposon family in Secalecereale

The chromosomal locations of a new class of Revolver transposon-like element were analyzed by using FISH method on the metaphase chromosome in somatic cell division of the rye cultivar Petkus. First, Revolver standard element probe was weakly hybridized throughout the rye chromosome and a comparatively large signal spotted with a dot-shape was detected. The dot-shape signal was stably detected at one place on the intercalated portion of the center of the short arm in chromosome 1R, two places near the end of the short arm and on the intercalated portion near the kinetochore in chromosome 2R, and one place on the intercalated portion of the center of short arm and two places near kinetochore and on the intercalated portion of the center of the long arm in chromosome 5R. The Revolver probe was effective for identification of 1R, 2R, and 5R chromosomes. On the other hand, Revolver non-autonomous element specific probe was strongly distributed throughout the rye chromosomes and considerable number and diverse lengths of transcripts were detected by RT-PCR. Although standard elements were found in localized clusters, the non-autonomous elements tended to be dispersed throughout the genome. Clustered nature of Revolver is significantly rare case in genomics.