title: Instability of the Arabidopsis mutant csn5a-2 caused by epigenetic modification of intronic T-DNA.
abstract: T-DNA insertion mutants play a crucial role in elucidating Arabidopsis gene function. In some cases, two or more T-DNA mutants are combined to study genetic interactions between homologous genes or genes hypothesized to act in the same pathway. We studied the significance of protein-protein interactions between CSN5A and ROP11 by crossing three independent rop11 T-DNA insertion mutants with csn5a-2, a partial loss-of-function intronic T-DNA insertion mutant. The csn5a-2 single mutant is severely stunted, but double rop11 csn5a-2mutants were rescued and exhibited increased CSN5A transcript and protein levels. The rescued phenotype was maintained in non-Mendelian fashion when the csn5a-2 single mutant was re-isolated from the rop11-1 csn5a-2 double mutant, and was sensitive to two inhibitors of DNA methylation. Loss of kanamycin resistance was also observed in re-isolated csn5a-2. These findings indicate that the rescue of csn5a-2 resulted from a trans T-DNA-mediated epigenetic effect on the csn5a-2 intronic T-DNA, similar to recent reports involving the intronic T-DNA mutants ag-TD, ben1-1, and cob-6. Thus the work reported here provides further support for the recommendation that mutants created through novel combinations of T-DNA alleles should be carefully evaluated for evidence of epigenetic modification of T-DNA before final conclusions are drawn.
authors.affiliation: Department of Forest Resources and Environmental Conservation, Virginia Tech, Blacksburg, VA 24061, USA.
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Jia
authors.affiliation: Department of Horticulture, Virginia Tech, Blacksburg, VA 24061, USA.
authors.forename: Bidisha
authors.initials: B
authors.lastname: Chanda
authors.affiliation: Department of Horticulture, Virginia Tech, Blacksburg, VA 24061, USA.
authors.forename: Mingzhe
authors.initials: M
authors.lastname: Zhao
authors.affiliation: Department of Forest Resources and Environmental Conservation, Virginia Tech, Blacksburg, VA 24061, USA.
authors.forename: Amy M
authors.initials: AM
authors.lastname: Brunner
authors.affiliation: Department of Horticulture, Virginia Tech, Blacksburg, VA 24061, USA. Electronic address: ebeers@vt.edu.
authors.forename: Eric P
authors.initials: EP
authors.lastname: Beers
mesh_terms: D017360:Arabidopsis / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D015153:Blotting, Western; D000075686:COP9 Signalosome Complex; D003562:Cytidine / Q000031:analogs & derivatives / Q000494:pharmacology; D019175:DNA Methylation / Q000187:drug effects / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics*; D044127:Epigenesis, Genetic / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D007438:Introns / Q000235:genetics*; D007613:Kanamycin Resistance / Q000187:drug effects / Q000235:genetics; D016254:Mutagenesis, Insertional / Q000187:drug effects / Q000235:genetics; D009154:Mutation / Q000235:genetics*; D010641:Phenotype; D011485:Protein Binding / Q000187:drug effects; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020798:Two-Hybrid System Techniques; D020741:rho GTP-Binding Proteins / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; C497728:COP9 signalosome subunit 5, Arabidopsis; D004269:DNA, Bacterial; D012333:RNA, Messenger; C036483:T-DNA; D003562:Cytidine; C009131:pyrimidin-2-one beta-ribofuranoside; D000075686:COP9 Signalosome Complex; C572957:ROP11 protein, Arabidopsis; D020741:rho GTP-Binding Proteins
keywords: CSN5A; Double mutant; Epigenetic; Intronic T-DNA; ROP GTPase; Yeast two-hybrid