title: AtPV42a and AtPV42b redundantly regulate reproductive development in Arabidopsis thaliana.
abstract: BACKGROUND
  The conserved SNF1/AMPK/SnRK1 complexes are global regulators of metabolic responses in eukaryotes and play a key role in the control of energy balance. Although α-type subunits of the SnRK1 complex have been characterized in several plant species, the biological function of β-type and γ-type subunits remains largely unknown. Here, we characterized AtPV42a and AtPV42b, the two homologous genes in Arabidopsis, which encode cystathionine-β-synthase (CBS) domain-containing proteins that belong to the PV42 class of γ-type subunits of the plant SnRK1 complexes.
  
  
  RESULTS
  Real-time polymerase chain reaction was performed to examine the expression of AtPV42a and AtPV42b in various tissues. Transgenic plants that expressed artificial microRNAs targeting these two genes were created. Reproductive organ development and fertilization in these plants were examined by various approaches, including histological analysis, scanning electron microscopy, transmission electron microscopy, and phenotypic analyses of reciprocal crosses between wild-type and transgenic plants. We found that AtPV42a and AtPV42b were expressed in various tissues during different developmental stages. Transgenic plants where AtPV42a and AtPV42b were simultaneously silenced developed shorter siliques and reduced seed sets. Such low fertility phenotype resulted from deregulation of late stamen development and impairment of pollen tube attraction conferred by the female gametophyte.
  
  
  CONCLUSIONS
  Our results demonstrate that AtPV42a and AtPV42b play redundant roles in regulating male gametogenesis and pollen tube guidance, indicating that the Arabidopsis SnRK1 complexes might be involved in the control of reproductive development.
authors.affiliation: Department of Biological Sciences and Temasek Life Sciences Laboratory, National University of Singapore, Singapore, Republic of Singapore.
authors.forename: Lei
authors.initials: L
authors.lastname: Fang
authors.forename: Xingliang
authors.initials: X
authors.lastname: Hou
authors.forename: Li Yen Candy
authors.initials: LY
authors.lastname: Lee
authors.forename: Lu
authors.initials: L
authors.lastname: Liu
authors.forename: Xiaojing
authors.initials: X
authors.lastname: Yan
authors.forename: Hao
authors.initials: H
authors.lastname: Yu
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics*; D017343:Genes, Plant; D035683:MicroRNAs / Q000235:genetics; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D008969:Molecular Sequence Data; D030821:Plants, Genetically Modified; D011058:Pollen / Q000648:ultrastructure; D016133:Polymerase Chain Reaction; D012098:Reproduction / Q000235:genetics; D017386:Sequence Homology, Amino Acid
chemical_list: D029681:Arabidopsis Proteins; D035683:MicroRNAs