title: Dramatic genotypic difference in, and effect of genetic crossing on, tissue culture-induced mobility of retrotransposon Tos17 in rice.
abstract: KEY MESSAGE                 :                                     We show for the first time that intraspecific crossing may impact mobility of the prominent endogenous retrotransposon                   Tos17                   under tissue culture conditions in rice.                                                                                     Tos17, an endogenous copia retrotransposon of rice, is transpositionally active in tissue culture. To study whether there exists fundamental genotypic difference in the tissue culture-induced mobility of Tos17, and if so, whether the difference is under genetic and/or epigenetic control, we conducted this investigation. We show that dramatic difference in tissue culture-induced Tos17 mobility exists among different rice pure-line cultivars sharing the same maternal parent: of the three lines studied that harbor Tos17, two showed mobilization of Tos17, which accrued in proportion to subculture duration, while the third line showed total quiescence (immobility) of the element and the fourth line did not contain the element. In reciprocal F1 hybrids between Tos17-mobile and -immobile (or absence) parental lines, immobility was dominant over mobility. In reciprocal F1 hybrids between both Tos17-mobile parental lines, an additive or synergistic effect on mobility of the element was noticed. In both types of reciprocal F1 hybrids, clear difference in the extent of Tos17 mobility was noted between crossing directions. Given that all lines share the same maternal parent, this observation indicates the existence of epigenetic parent-of-origin effect. We conclude that the tissue culture-induced mobility of Tos17 in rice is under complex genetic and epigenetic control, which can be either enhanced or repressed by intraspecific genetic crossing.
authors.affiliation: Key Laboratory of Molecular Epigenetics of MOE, Northeast Normal University, Changchun, 130024, China.
authors.forename: Chunjing
authors.initials: C
authors.lastname: Lin
authors.forename: Xiuyun
authors.initials: X
authors.lastname: Lin
authors.forename: Lanjuan
authors.initials: L
authors.lastname: Hu
authors.forename: Jingjing
authors.initials: J
authors.lastname: Yang
authors.forename: Tianqi
authors.initials: T
authors.lastname: Zhou
authors.forename: Likun
authors.initials: L
authors.lastname: Long
authors.forename: Chunming
authors.initials: C
authors.lastname: Xu
authors.forename: Shaochen
authors.initials: S
authors.lastname: Xing
authors.forename: Bao
authors.initials: B
authors.lastname: Qi
authors.forename: Yingshan
authors.initials: Y
authors.lastname: Dong
authors.forename: Bao
authors.initials: B
authors.lastname: Liu
mesh_terms: D015139:Blotting, Southern; D003433:Crosses, Genetic; D056915:DNA Copy Number Variations; D018744:DNA, Plant / Q000235:genetics; D044127:Epigenesis, Genetic; D018745:Genome, Plant / Q000235:genetics; D005838:Genotype; D012275:Oryza / Q000235:genetics*; D018626:Retroelements / Q000235:genetics*; D046509:Tissue Culture Techniques
chemical_list: D018744:DNA, Plant; D018626:Retroelements