Transgenerational activation of an autonomous DNA transposon, Dart1-24, by 5-azaC treatment in rice

Hideki Nishimura, Eiko Himi, Chang-Ho Eun, Hidekazu Takahashi, Qian Qian, Kazuo Tsugane, Masahiko Maekawa

Theoretical and Applied Genetics; December 2019, Volume 132, Issue 12, pp 3347–3355

Key message

Dart1-24, one of the 37 autonomous DNA transposon Dart1s, was heritably activated by the demethylation of the 5′ region following 5-azaC treatment of rice seeds.

Abstract

Transposons are controlled by epigenetic regulations. To obtain newly activated autonomous elements of Dart1, a DNA transposon, in rice, seeds of a stable pale yellow leaf (pyl-stb) mutant caused by the insertion of nDart1-0, a nonautonomous element in OsClpP5, were treated with 5-azaC, a demethylating agent. In the 5-azaC-treated M1 plants, 60–70% of the plants displayed variegated pale yellow leaf (pyl-v) phenotype, depending on the concentration of 5-azaC used, suggesting that inactivated Dart1 might become highly activated by 5-azaC treatment and nDart1-0 was excised from OsClpP5 by the activated Dart1s. Although the M2 plants derived from most of these pyl-v plants showed stable pyl phenotypes, some variegated M1 plants generated pyl-v M2 progeny. These results indicated that most M1 pyl-v phenotypes at M1 were not heritable. Dart1-24, 1-27 and 1-28 were expressed in the M2 pyl-v plants, and mapping analysis confirmed that Dart1-24 was newly activated. Further, the transgenerational activation of Dart1-24 was demonstrated to be caused by the demethylation of nucleotides in its 5′ region.

See https://link.springer.com/article/10.1007/s00122-019-03429-7