title: Programmed cell death may act as a surveillance mechanism to safeguard male gametophyte development in Arabidopsis.
abstract: Programmed cell death (PCD) plays an important role in plant growth and development as well as in stress responses. During male gametophyte development, it has been proposed that PCD may act as a cellular surveillance mechanism to ensure successful progression of male gametogenesis, and this suicide protective machinery is repressed under favorable growth conditions. However, the regulatory mechanism of male gametophyte-specific PCD remains unknown. Here, we report the use of a TdT-mediated dUTP nick-end labeling-based strategy for genetic screening of Arabidopsis mutants that present PCD phenotype during male gametophyte development. By using this approach, we identified 12 mutants, designated as pcd in male gametogenesis (pig). pig mutants are defective at various stages of male gametophyte development, among which nine pig mutants show a microspore-specific PCD phenotype occurring mainly around pollen mitosis I or the bicellular stage. The PIG1 gene was identified by map-based cloning, and was found to be identical to ATAXIA TELANGIECTASIA MUTATED (ATM), a highly conserved gene in eukaryotes and a key regulator of the DNA damage response. Our results suggest that PCD may act as a general mechanism to safeguard the entire process of male gametophyte development.
authors: State Key Laboratory of Plant Genomics and National Plant Gene Research Center, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.
authors: Jian
authors: J
authors: Zhang
authors: Chong
authors: C
authors: Teng
authors: Yan
authors: Y
authors: Liang
mesh_terms: D017209:Apoptosis; D017360:Arabidopsis / Q000166:cytology / Q000235:genetics / Q000254:growth & development* / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D064007:Ataxia Telangiectasia Mutated Proteins; D001483:Base Sequence; D002467:Cell Nucleus / Q000378:metabolism; D002874:Chromosome Mapping; D053938:DNA Fragmentation; D017343:Genes, Plant; D008938:Mitosis; D008969:Molecular Sequence Data; D009154:Mutation; D010641:Phenotype; D011058:Pollen / Q000166:cytology / Q000235:genetics / Q000254:growth & development* / Q000502:physiology
chemical_list: C576589:ATM protein, Arabidopsis; D029681:Arabidopsis Proteins; D064007:Ataxia Telangiectasia Mutated Proteins