AUTHOR=Niu Xiaoying , Chen Lu , Kato Atsushi , Ito Hidetaka 

TITLE=Regulatory mechanism of a heat-activated retrotransposon by DDR complex in Arabidopsis thaliana

JOURNAL=Frontiers in Plant Science

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2022.1048957

DOI=10.3389/fpls.2022.1048957

ISSN=1664-462X

ABSTRACT=<p>The RNA-directed DNA methylation (RdDM) pathway plays an essential role in the transposon silencing mechanism; the DDR complex, consisting of DRD1, DMS3, and RDM1, is an essential component of the RdDM pathway. <italic>ONSEN</italic>, identified in <italic>Arabidopsis</italic>, is a retrotransposon activated by heat stress at 37°C; however, studies on the regulation of <italic>ONSEN</italic> are limited. In this study, we analyzed the regulation of <italic>ONSEN</italic> activity by the DDR complex in <italic>Arabidopsis</italic>. We elucidated that loss of any component of the DDR complex increased <italic>ONSEN</italic> transcript levels. Transgenerational transposition of <italic>ONSEN</italic> was observed in the DDR-complex mutants treated with heat stress for 48 h. Furthermore, the DDR complex components DRD1, DMS3, and RDM1 played independent roles in suppressing <italic>ONSEN</italic> transcription and transposition. Moreover, we found that the duration of heat stress affects <italic>ONSEN</italic> activity. Therefore, the results of this study provide new insights into the retrotransposon regulatory mechanisms of the DDR complex in the RdDM pathway.</p>