Overexpression of the Downward Leaf Curling (DLC) Gene from Melon Changes Leaf Morphology by Controlling Cell Size and Shape in Arabidopsis Leaves

  • Kee, Jae-Jun (Department of Biology, University of Incheon) ;
  • Jun, Sang Eun (Department of Molecular Biotechnology, Dong-A University) ;
  • Baek, Seung-A (Department of Biology, University of Incheon) ;
  • Lee, Tae-Soo (Department of Biology, University of Incheon) ;
  • Cho, Myung Rae (National Institute of Agricultural Biotechnology, Rural Development Administration) ;
  • Hwang, Hyun-Sik (Department of Genetic Engineering, Sungkyunkwan University) ;
  • Lee, Suk-Chan (Department of Genetic Engineering, Sungkyunkwan University) ;
  • Kim, Jongkee (Department of Applied Plant Science, Chung-Ang University) ;
  • Kim, Gyung-Tae (Department of Molecular Biotechnology, Dong-A University) ;
  • Im, Kyung-Hoan (Department of Biology, University of Incheon)
  • Received : 2009.04.30
  • Accepted : 2009.06.15
  • Published : 2009.08.31


A plant-specific gene was cloned from melon fruit. This gene was named downward leaf curling (CmDLC) based on the phenotype of transgenic Arabidopsis plants overexpressing the gene. This expression level of this gene was especially upregulated during melon fruit enlargement. Overexpression of CmDLC in Arabidopsis resulted in dwarfism and narrow, epinastically curled leaves. These phenotypes were found to be caused by a reduction in cell number and cell size on the adaxial and abaxial sides of the epidermis, with a greater reduction on the abaxial side of the leaves. These phenotypic characteristics, combined with the more wavy morphology of epidermal cells in overexpression lines, indicate that CmDLC overexpression affects cell elongation and cell morphology. To investigate intracellular protein localization, a CmDLC-GFP fusion protein was made and expressed in onion epidermal cells. This protein was observed to be preferentially localized close to the cell membrane. Thus, we report here a new plant-specific gene that is localized to the cell membrane and that controls leaf cell number, size and morphology.


Supported by : University of Incheon


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