Analysis of fast neutron-generated mutants at the Arabidopsis thaliana HY4 locus.
Ionizing radiation is expected to produce mutants with deletions or other chromosomal rearrangements. These mutants are useful for a variety of purposes, such as creating null alleles and cloning genes whose existence is known only from their mutant phenotype; however, only a few mutations generated by ionizing radiation have been characterized at the molecular level in Arabidopsis thaliana. Twenty fast neutron-generated alleles of the Arabidopsis HY4 locus, which encodes a blue light receptor, CRY1, were isolated and characterized. Nine of the mutant alleles displayed normal genetic behavior. The other 11 mutant alleles were poorly transmitted through the male gametophyte and were lethal in homozygous plants. Southern blot analysis demonstrated that alleles of the first group generally contain small or moderate-sized deletions at HY4, while alleles of the second group contain large deletions at this locus. These results demonstrate that fast neutrons can produce a range of deletions at a single locus in Arabidopsis. Many of these deletions would be suitable for cloning by genomic subtraction or representational difference analysis. The results also suggest the presence of an essential locus adjacent to HY4.
Cell Biology and Metabolism Branch, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892-5430, USA.
E
E
Bruggemann
K
K
Handwerger
C
C
Essex
G
G
Storz
D000483:Alleles; D017360:Arabidopsis / Q000235:genetics* / Q000528:radiation effects*; D029681:Arabidopsis Proteins; D015139:Blotting, Southern; D003433:Crosses, Genetic; D056931:Cryptochromes; D029721:Drosophila Proteins; D005136:Eye Proteins; D005420:Flavoproteins / Q000235:genetics*; D017343:Genes, Plant; D005838:Genotype; D009154:Mutation; D009502:Neutrons; D010641:Phenotype; D017956:Photoreceptor Cells, Invertebrate; D010940:Plant Proteins / Q000235:genetics*; D011839:Radiation, Ionizing; D043562:Receptors, G-Protein-Coupled; D012641:Selection, Genetic; D017384:Sequence Deletion
D029681:Arabidopsis Proteins; C538962:CRY1 protein, Arabidopsis; C538963:CRY1 protein, human; D056931:Cryptochromes; D029721:Drosophila Proteins; D005136:Eye Proteins; D005420:Flavoproteins; D010940:Plant Proteins; D043562:Receptors, G-Protein-Coupled; C119828:cry protein, Drosophila