Title | Reciprocal chromosome translocation associated with TDNA-insertion mutation in Arabidopsis: genetic and cytological analyses of consequences for gametophyte development and for construction of doubly mutant lines. |
Publication Type | Journal Article |
Year of Publication | 2009 |
Authors | Curtis MJ, Belcram K, Bollmann SR, Tominey CM, Hoffman PD, Mercier R, Hays JB |
Journal | Planta |
Volume | 229 |
Issue | 4 |
Pagination | 731-45 |
Date Published | 2009 Mar |
ISSN | 1432-2048 |
Arabidopsis, Arabidopsis Proteins, Chromosomes, Plant, DNA, Bacterial, DNA-Directed DNA Polymerase, Flowers, Gene Frequency, Genotype, Heterozygote, In Situ Hybridization, Fluorescence, Models, Genetic, Mutagenesis, Insertional, Mutation, Pollen, Translocation, Genetic | |
Chromosomal rearrangements may complicate construction of Arabidopsis with multiple TDNA-insertion mutations. Here, crossing two lines homozygous for insertions in AtREV3 and AtPOLH (chromosomes I and V, respectively) and selfing F1 plants yielded non-Mendelian F2 genotype distributions: frequencies of +/++/+ and 1/1 2/2 progeny were only 0.42 and 0.25%. However, the normal development and fertility of double mutants showed AtPOLH-1 and AtREV3-2 gametes and 1/1 2/2 embryos to be fully viable. F2 distributions could be quantitatively predicted by assuming that F1 selfing produced inviable (1,2) and (+,+) gametophytes 86% of the time. Some defect intrinsic to the F1 selfing process itself thus appeared responsible. In selfing AtREV3 (+/2 ) single mutants, imaging of ovules and pollen showed arrest or abortion, respectively, of half of gametophytes; however, gametogenesis was normal in AtREV3 ( 2/2 ) homozygotes. These findings, taken together, suggested that T-DNA insertion at AtREV3 on chromosome I had caused a reciprocal I-V translocation. Spreads of meiosis I chromosomes in selfing AtREV3 (+/2 ) heterozygotes revealed the predicted cruciform four-chromosome structures, which fluorescence in situ hybridization showed to invariably include both translocated and normal chromosomes I and V. Sequencing of the two junctions of T-DNA with AtREV3 DNA and the two with gene At5g59920 suggested translocation via homologous recombination between independent inverted-repeat T-DNA insertions. Thus, when crosses between TDNA-insertion mutants yield anomalous progeny distributions, TDNA-linked translocations should be considered. | |
10.1007/s00425-008-0868-0 | |
Alternate Journal | Planta |
PubMed ID | 19082841 |
PubMed Central ID | PMC4186712 |
Grant List | T32 ES007060 / ES / NIEHS NIH HHS / United States |