title: Functional identification and characterization of the Brassica napus transcription factor gene BnAP2, the ortholog of Arabidopsis thaliana APETALA2.
abstract: BnAP2, an APETALA2 (AP2)-like gene, has been isolated from Brassica napus cultivar Zhongshuang 9. The cDNA of BnAP2, with 1, 299 bp in length, encoded a transcription factor comprising of 432 amino acid residues. Results from complementary experiment indicated that BnAP2 was completely capable of restoring the phenotype of Arabidopsis ap2-11 mutant. Together with the sequence and expression data, the complementation data suggested that BnAP2 encodes the ortholog of AtAP2. To address the transcriptional activation of BnAP2, we performed transactivation assays in yeast. Fusion protein of BnAP2 with GAL4 DNA binding domain strongly activated transcription in yeast, and the transactivating activity of BnAP2 was localized to the N-terminal 100 amino acids. To further study the function of BnAP2 involved in the phenotype of B. napus, we used a transgenic approach that involved targeted RNA interference (RNAi) repression induced by ihp-RNA. Floral various phenotype defectives and reduced female fertility were observed in B. napus BnAP2-RNAi lines. Loss of the function of BnAP2 gene also resulted in delayed sepal abscission and senescence with the ethylene-independent pathway. In the strong BnAP2-RNAi lines, seeds showed defects in shape, structure and development and larger size. Strong BnAP2-RNAi and wild-type seeds initially did not display a significant difference in morphology at 10 DAF, but the development of BnAP2-RNAi seeds was slower than that of wild type at 20 DAF, and further at 30 DAF, wild-type seeds were essentially at their final size, whereas BnAP2-RNAi seeds stopped growing and developing and gradually withered.
authors.affiliation: Key Laboratory of Oil Crop Biology and Genetic Breeding of the Ministry of Agriculture, Institute of Oil Crops, Chinese Academy of Agricultural Sciences, Wuhan, China.
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Yan
authors.forename: Lei
authors.initials: L
authors.lastname: Zhang
authors.forename: Bo
authors.initials: B
authors.lastname: Chen
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Xiong
authors.forename: Chunli
authors.initials: C
authors.lastname: Chen
authors.forename: Lijun
authors.initials: L
authors.lastname: Wang
authors.forename: Jingyin
authors.initials: J
authors.lastname: Yu
authors.forename: Changming
authors.initials: C
authors.lastname: Lu
authors.forename: Wenhui
authors.initials: W
authors.lastname: Wei
mesh_terms: D000375:Aging / Q000235:genetics; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D029688:Brassica napus / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism*; D005030:Ethylenes / Q000494:pharmacology; D005298:Fertility / Q000235:genetics; D035264:Flowers / Q000378:metabolism; D018628:Gene Dosage; D020869:Gene Expression Profiling; D023061:Gene Order; D005816:Genetic Complementation Test; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism; D010641:Phenotype; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism*; D030821:Plants, Genetically Modified; D012639:Seeds / Q000378:metabolism; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism*; D015533:Transcriptional Activation; D015003:Yeasts / Q000235:genetics / Q000378:metabolism
chemical_list: C499534:APETALA2 protein, Arabidopsis; D029681:Arabidopsis Proteins; D005030:Ethylenes; D018398:Homeodomain Proteins; D009687:Nuclear Proteins; D010940:Plant Proteins; D014157:Transcription Factors; C036216:ethylene