title: Exon skipping of AGAMOUS homolog PrseAG in developing double flowers of Prunus lannesiana (Rosaceae).
abstract: KEY MESSAGE                 :                                     Two transcript isoforms of                   AGAMOUS                   homologs, from single and double flower                   Prunus lannesiana,                   respectively, showed different functions.                                                                  The Arabidopsis floral homeotic C function gene AGAMOUS (AG) confers stamen and carpel identity. Loss of AG function results in homeotic conversions of stamens into petals and formation of double flowers. In order to present a molecular dissection of a double-flower cultivar in Prunus lannesiana (Rosaceae), we isolated and identified a single-copy gene, AG homolog from two genetically cognate P. lannesiana bearing single and double flowers, respectively. Sequence analysis revealed that the AG homolog, prseag-1, from double flowers showed a 170-bp exon skipping as compared to PrseAG (Prunus serrulata AGAMOUS) from the single flowers. Genomic DNA sequence revealed that abnormal splicing resulted in mutant prseag-1 protein with the C-terminal AG motifs I and II deletions. In addition, protein sequence alignment and phylogenetic analyses revealed that the PrseAG was grouped into the euAG lineage. A semi-quantitative PCR analysis showed that the expression of PrseAG was restricted to reproductive organs of stamens and carpels in single flowers of P. lannesiana 'speciosa', while the prseag-1 mRNA was highly transcribed throughout the petals, stamens, and carpels in double flowers from 'Albo-rosea'. The transgenic Arabidopsis containing 35S::PrseAG displayed extremely early flowering, bigger stamens and carpels and homeotic conversion of petals into staminoid organs, but ectopic expression of prseag-1 could not mimic the phenotypic ectopic expression of PrseAG in Arabidopsis. In general, this study provides evidences to show that double flower 'Albo-rosea' is a putative C functional ag mutant in P. lannesiana.
authors.affiliation: College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, Beijing 100083, PR China. zxliu1977@yahoo.com.cn
authors.forename: Zhixiong
authors.initials: Z
authors.lastname: Liu
authors.forename: Dandan
authors.initials: D
authors.lastname: Zhang
authors.forename: Di
authors.initials: D
authors.lastname: Liu
authors.forename: Fenglan
authors.initials: F
authors.lastname: Li
authors.forename: Hai
authors.initials: H
authors.lastname: Lu
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism; D003001:Cloning, Molecular; D017124:Conserved Sequence; D005091:Exons / Q000235:genetics; D035264:Flowers / Q000033:anatomy & histology / Q000235:genetics* / Q000254:growth & development / Q000502:physiology; D018506:Gene Expression Regulation, Plant; D026161:MADS Domain Proteins / Q000235:genetics / Q000378:metabolism*; D010641:Phenotype; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D011058:Pollen / Q000166:cytology / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D027861:Prunus / Q000033:anatomy & histology / Q000235:genetics* / Q000254:growth & development / Q000502:physiology; D059368:RNA Isoforms / Q000235:genetics*; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA
chemical_list: D026161:MADS Domain Proteins; D010940:Plant Proteins; D059368:RNA Isoforms