title: A small RNA mediated regulation of a stress-activated retrotransposon and the tissue specific transposition during the reproductive period in Arabidopsis.
abstract: Transposable elements (TEs) are key elements that facilitate genome evolution of the host organism. A number of studies have assessed the functions of TEs, which change gene expression in the host genome. Activation of TEs is controlled by epigenetic modifications such as DNA methylation and histone modifications. Several recent studies have reported that TEs can also be activated by biotic or abiotic stress in some plants. We focused on a Ty1/copia retrotransposon, ONSEN, that is activated by heat stress (HS) in Arabidopsis. We found that transcriptional activation of ONSEN was regulated by a small interfering RNA (siRNA)-related pathway, and the activation could also be induced by oxidative stress. Mutants deficient in siRNA biogenesis that were exposed to HS at the initial stages of vegetative growth showed transgenerational transposition. The transposition was also detected in the progeny, which originated from tissue that had differentiated after exposure to the HS. The results indicated that in some undifferentiated cells, transpositional activity could be maintained quite long after exposure to the HS.
authors.affiliation: Faculty of Science, Hokkaido University, Sapporo Japan.
authors.forename: Wataru
authors.initials: W
authors.lastname: Matsunaga
authors.affiliation: Laboratory of Plant Molecular Physiology, Graduate School of Agricultural and Life Sciences, University of Tokyo, Tokyo Japan.
authors.forename: Naohiko
authors.initials: N
authors.lastname: Ohama
authors.affiliation: Department of Advanced Bioscience, Faculty of Agriculture, Kinki University, Nara Japan.
authors.forename: Noriaki
authors.initials: N
authors.lastname: Tanabe
authors.affiliation: Faculty of Science, Hokkaido University, Sapporo Japan.
authors.forename: Yukari
authors.initials: Y
authors.lastname: Masuta
authors.affiliation: Faculty of Science, Hokkaido University, Sapporo Japan.
authors.forename: Seiji
authors.initials: S
authors.lastname: Masuda
authors.affiliation: Institute of Plant Science and Resources, Okayama University, Kurashiki Japan.
authors.forename: Namiki
authors.initials: N
authors.lastname: Mitani
authors.affiliation: Laboratory of Plant Molecular Physiology, Graduate School of Agricultural and Life Sciences, University of Tokyo, Tokyo Japan.
authors.forename: Kazuko
authors.initials: K
authors.lastname: Yamaguchi-Shinozaki
authors.affiliation: Institute of Plant Science and Resources, Okayama University, Kurashiki Japan.
authors.forename: Jian F
authors.initials: JF
authors.lastname: Ma
authors.affiliation: Faculty of Science, Hokkaido University, Sapporo Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Kato
authors.affiliation: Faculty of Science, Hokkaido University, Sapporo Japan ; PRESTO, Japan Science and Technology Agency, Kawaguchi Japan.
authors.forename: Hidetaka
authors.initials: H
authors.lastname: Ito
keywords: Arabidopsis thaliana; ONSEN; environmental stress; small RNA; transposon