Localization of T-DNA Insertions in Petunia by Fluorescence in Situ Hybridization: Physical Evidence for Suppression of Recombination

Autor: Bob M. Montijn, Paul Fransz, O. Oud, R. ten Hoopen, Nanne Nanninga, A.G.M. Gerats, T. P. Robbins
Přispěvatelé: Molecular Cytology (SILS, FNWI)
Rok vydání: 1996
Předmět:
Zdroj: The Plant Cell, 8(5), 823-830. American Society of Plant Biologists
Scopus-Elsevier
ISSN: 1532-298X
1040-4651
DOI: 10.1105/tpc.8.5.823
Popis: Using fluorescence in situ hybridization (FISH) with metaphase preparations, we localized a 4-kb single-copy T-DNA sequence in a group of petunia transformants. The selected T-DNAs previously had been shown to be linked to the phenotypic marker FI on chromosome II. Linkage analysis had revealed that recombination around the FI locus is suppressed in a wide cross relative to an inbred recombination assay. The localization of six FI-linked T-DNAs and the FI locus itself, using FISH, revealed a number of aspects of recombination in petunia: (1) the central region of chromosome II showed at least a 10-fold suppression of recombination in wide crosses relative to the distal region; (2) recombination in wide hybrids over two-thirds of the chromosome was extremely low; and (3) recombination between completely homologous chromosomes in an inbred cross also was suppressed in the central region. In addition, the T-DNAs were not evenly distributed along the chromosome, suggesting a possible preference for a distal position for T-DNA integration. Implications for such a preference are discussed.
Databáze: OpenAIRE