title: Genome Sequencing of Arabidopsis abp1-5 Reveals Second-Site Mutations That May Affect Phenotypes.
abstract: Auxin regulates numerous aspects of plant growth and development. For many years, investigating roles for AUXIN BINDING PROTEIN1 (ABP1) in auxin response was impeded by the reported embryo lethality of mutants defective in ABP1. However, identification of a viable Arabidopsis thaliana TILLING mutant defective in the ABP1 auxin binding pocket (abp1-5) allowed inroads into understanding ABP1 function. During our own studies with abp1-5, we observed growth phenotypes segregating independently of the ABP1 lesion, leading us to sequence the genome of the abp1-5 line described previously. We found that the abp1-5 line we sequenced contains over 8000 single nucleotide polymorphisms in addition to the ABP1 mutation and that at least some of these mutations may originate from the Arabidopsis Wassilewskija accession. Furthermore, a phyB null allele in the abp1-5 background is likely causative for the long hypocotyl phenotype previously attributed to disrupted ABP1 function. Our findings complicate the interpretation of abp1-5 phenotypes for which no complementation test was conducted. Our findings on abp1-5 also provide a cautionary tale illustrating the need to use multiple alleles or complementation lines when attributing roles to a gene product.
authors.affiliation: Department of Biology, Washington University, St. Louis, Missouri 63130.
authors.forename: Tara A
authors.initials: TA
authors.lastname: Enders
authors.affiliation: Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, Michigan 48824.
authors.forename: Sookyung
authors.initials: S
authors.lastname: Oh
authors.affiliation: Center for Plant Cell Biology, Department of Botany and Plant Sciences, University of California, Riverside, California 92521.
authors.forename: Zhenbiao
authors.initials: Z
authors.lastname: Yang
authors.affiliation: Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, Michigan 48824 Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824.
authors.forename: Beronda L
authors.initials: BL
authors.lastname: Montgomery
authors.affiliation: Department of Biology, Washington University, St. Louis, Missouri 63130 strader@wustl.edu.
authors.forename: Lucia C
authors.initials: LC
authors.lastname: Strader
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000528:radiation effects; D029681:Arabidopsis Proteins / Q000235:genetics; D018745:Genome, Plant; D060005:Genotyping Techniques; D018546:Hypocotyl / Q000254:growth & development / Q000528:radiation effects; D008027:Light; D009154:Mutation / Q000235:genetics*; D010641:Phenotype; D051939:Phytochrome B / Q000235:genetics; D010940:Plant Proteins / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D011956:Receptors, Cell Surface / Q000235:genetics*; D017422:Sequence Analysis, DNA; D015398:Signal Transduction / Q000528:radiation effects
chemical_list: D029681:Arabidopsis Proteins; C497952:PHYB protein, Arabidopsis; D010940:Plant Proteins; D011956:Receptors, Cell Surface; C083846:auxin-binding protein 1; D051939:Phytochrome B