Functional characterization of an apple apomixis-related MhFIE gene in reproduction development.
The products of the FIS genes play important regulatory roles in diverse developmental processes, especially in seed formation after fertilization. In this study, a FIS-class gene MhFIE was isolated from apple. It encoded a predicted protein highly similar to polycomb group (PcG) protein FERTILIZATION-INDEPENDENT ENDOSPERM (FIE). MhFIE functioned as an Arabidopsis FIE homologue, as indicated by functional complementation experiment using Arabidopsis fie mutant. In addition, BiFC assay showed that MhFIE protein interacted with AtCLF. Furthermore, transgenic Arabidopsis ectopically expressing MhFIE produced less APETALA3 (AtAP3) and AGAMOUS (AtAG) transcripts than WT control, and therefore exhibited abnormal flower, seed development. These results suggested that polycomb complex including FIE and CLF proteins played an important role in reproductive development by regulating the expression of its downstream genes. In addition, it was found that MhFIE constitutively expressed in various tissues tested. Its expression levels were lower in apomictic apple species than the sexual reproductive species, suggested it was possibly involved into apomixis in apple. Furthermore, the hybrids of tea crabapple generated MhFIE transcripts at different levels. The parthenogenesis capacity was negatively correlated with MhFIE expression level in these hybrids. These results suggested that MhFIE was involved into the regulation of flower development and apomixis in apple.
State Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai-An, Shandong 271018, China.
Dan-Dan
DD
Liu
Qing-Long
QL
Dong
Chao
C
Sun
Qing-Lian
QL
Wang
Chun-Xiang
CX
You
Yu-Xin
YX
Yao
Yu-Jin
YJ
Hao
D000595:Amino Acid Sequence; D060832:Apomixis / Q000235:genetics; D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development / Q000502:physiology* / Q000648:ultrastructure; D002467:Cell Nucleus / Q000378:metabolism; D035264:Flowers / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D005816:Genetic Complementation Test; D027845:Malus / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D019697:Onions / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure; D010312:Parthenogenesis / Q000502:physiology*; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified; D063146:Polycomb-Group Proteins / Q000235:genetics / Q000378:metabolism; D025941:Protein Interaction Mapping; D012098:Reproduction / Q000235:genetics; D012639:Seeds / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA
D010940:Plant Proteins; D063146:Polycomb-Group Proteins