Analysis of mobilization of transposable elements in a mutable rice Isehikari

Abstract

A japonica rice Isehikari, which is believed as a natural mutant of Koshihikari, is known to yield various mutants under natural conditions though at low frequency. In this study, we investigated the mobilization of transposable elements, mPing and nDart, in Isehikari. Transposon display analyses revealed that the insertion polymorphisms and copy number variations of both mPing and nDart were found between Isehikari and Koshihikari, indicating that mPing and nDart might have mobilized at the timing when Isehikari was derived from Koshihikari. However, transposon display analyses using 100 progenies derived from two single selfed plants of Isehikari showed no evidence that mPing and nDart are still actively transposing in Isehikari. These results indicate that mPing and nDart might be inactive or less active in intact plants of Isehikari grown under natural conditions.