title: Developmental defects and seedling lethality in apyrase AtAPY1 and AtAPY2 double knockout mutants.
abstract: Previously it was shown that the Arabidopsis apyrase genes AtAPY1 and AtAPY2 are crucial for male fertility because mutant pollen (apy1-1; apy2-1) with T-DNA insertions in both genes could not germinate (Steinebrunner et al. (2003) Plant Physiol. 131: 1638-1647). In this study, pollen germination was restored and apyrase T-DNA double knockouts (DKO) apy1-1/apy1-1; apy2-1/apy2-1 were generated by complementation with AtAPY2 under the control of a pollen-specific promoter. The DKO phenotype displayed developmental defects including the lack of functional root and shoot meristems. In cotyledons, morphogenetic and patterning abnormalities were apparent, e.g., unlobed pavement cells and stomatal clusters. Another set of lines was created which carried either AtAPY1 or AtAPY2 under a dexamethasone-(DEX)-inducible promoter as an additional transgene to the pollen-specific gene construct. Application of DEX did not reverse the DKO phenotype to wild-type, but some inducible lines exhibited less severe defects even in the absence of the inducer, probably due to some background expression. However, even these DKO mutants were seedling-lethal and shared other defects regarding cell division, cell expansion and stomatal patterning. Taken together, the defects in the DKO mutants demonstrate that AtAPY1 and AtAPY2 are essential for normal plant development.
authors.affiliation: Department of Biology, Section of Molecular Biotechnology, Technical University of Dresden, 01062, Dresden, Germany.
authors.forename: Carolin
authors.initials: C
authors.lastname: Wolf
authors.forename: Maria
authors.initials: M
authors.lastname: Hennig
authors.forename: Dwight
authors.initials: D
authors.lastname: Romanovicz
authors.forename: Iris
authors.initials: I
authors.lastname: Steinebrunner
mesh_terms: D001081:Apyrase / Q000235:genetics*; D017360:Arabidopsis / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000235:genetics*; D002455:Cell Division; D018744:DNA, Plant / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D005816:Genetic Complementation Test; D008957:Models, Genetic; D009154:Mutation; D010641:Phenotype; D030821:Plants, Genetically Modified / Q000235:genetics*; D053205:Pollen Tube / Q000378:metabolism; D011401:Promoter Regions, Genetic; D036226:Seedlings / Q000235:genetics*; D019076:Transgenes
chemical_list: D029681:Arabidopsis Proteins; D018744:DNA, Plant; C522733:APY1 protein, Arabidopsis; C522734:APY2 protein, Arabidopsis; D001081:Apyrase