title: Kiwifruit floral gene APETALA2 is alternatively spliced  and accumulates in aberrant indeterminate flowers  in the absence of miR172.
abstract: In Arabidopsis, the identity of perianth and reproductive organs are specified by antagonistic action of two floral homeotic genes, APETALA2 (AP2) and AGAMOUS (AG). AP2 is also negatively regulated by an evolutionary conserved interaction with a microRNA, miR172, and has additional roles in general plant development. A kiwifruit gene with high levels of homology to AP2 and AP2-like genes from other plant species was identified. The transcript was abundant in the kiwifruit flower, particularly petal, suggesting a role in floral organ identity. Splice variants were identified, all containing both AP2 domains, including a variant that potentially produces a shorter transcript without the miRNA172 targeting site. Increased AP2 transcript accumulation was detected in the aberrant flowers of the mutant ‘Pukekohe dwarf’ with multiple perianth whorls and extended petaloid features. In contrast to normal kiwifruit flowers, the aberrant flowers failed to accumulate miR172 in the developing whorls, although accumulation was detected at the base of the flower. An additional role during dormancy in kiwifruit was proposed based on AP2 transcript accumulation in axillary buds before and after budbreak.
authors.affiliation: The New Zealand Institute for Plant & Food Research Mt Albert, Auckland Mail Centre, Private Bag 92169, Auckland 1142, New Zealand. erika.varkonyi-gasic@plantandfood.co.nz
authors.forename: Erika
authors.initials: E
authors.lastname: Varkonyi-Gasic
authors.forename: Robyn H
authors.initials: RH
authors.lastname: Lough
authors.forename: Sarah M A
authors.initials: SM
authors.lastname: Moss
authors.forename: Rongmei
authors.initials: R
authors.lastname: Wu
authors.forename: Roger P
authors.initials: RP
authors.lastname: Hellens
mesh_terms: D029042:Actinidia / Q000235:genetics*; D017398:Alternative Splicing; D000595:Amino Acid Sequence; D029681:Arabidopsis Proteins / Q000235:genetics; D035264:Flowers / Q000235:genetics* / Q000254:growth & development*; D018506:Gene Expression Regulation, Plant; D018398:Homeodomain Proteins / Q000235:genetics; D035683:MicroRNAs; D008969:Molecular Sequence Data; D009154:Mutation; D009687:Nuclear Proteins / Q000235:genetics; D010802:Phylogeny; D012621:Seasons; D012689:Sequence Homology, Nucleic Acid
chemical_list: C499534:APETALA2 protein, Arabidopsis; D029681:Arabidopsis Proteins; D018398:Homeodomain Proteins; D035683:MicroRNAs; D009687:Nuclear Proteins