| Institution: | Department of Genetics, Institute for Molecular Biological Sciences, Vrije Universiteit, BioCentrum Amsterdam, de Boelelaan 1087, 1081 HV Amsterdam, The NetherlandsSummaryFifty new flower pigmentation mutants in;Petunia hybrida using endogenous transposable elements (TEs) as a mutagen were generated. Forty‐six mutants displayed somatic and sporogenic instability indicating that they were caused by a TE. Phenotypic analysis showed that the mutation altered either anthocyanin biosynthesis (40 alleles for seven loci), the intracellular pH of petals (six alleles for three loci) or the shape of petal cells (two alleles for two loci). To identify the TEs reponsible for the mutations, the authors subjected 16 alleles of theanthocyanin‐3(an3) locus, encoding flavanone 3β‐hydroxylase, to molecular analysis. This showed that 11 out of 12 unstablean3alleles harboured TE insertions of a single family,dTph1, while one allele harboured a new 177 bp TE designateddTph2.In addition, the authors found onean3allele (an3‐W138A) in which adTph1element had inserted 30 bp upstream the translation start, without inactivating the gene. This 'cryptic' element was responsible for the creation of a stable recessive (untagged)an3allele, where a large rearrangement inactivated the gene. These findings indicate that mutants for novel loci are most likely tagged bydTph1elements opening the way for their isolation.Introduction |
