title: A Strategy to Validate the Role of Callose-mediated Plasmodesmal Gating in the Tropic Response.
abstract: The plant hormone auxin plays an important role in many growth and developmental processes, including tropic responses to light and gravity. The establishment of an auxin gradient is a key event leading to phototropism and gravitropism. Previously, polar auxin transport (PAT) was shown to establish an auxin gradient in different cellular domains of plants. However, Han et al. recently demonstrated that for proper auxin gradient formation, plasmodesmal callose-mediated symplasmic connectivity between the adjacent cells is also a critical factor. In this manuscript, the strategy to elucidate the role of particular genes, which can affect phototropism and gravitropism by altering the symplasmic connectivity through modulating plasmodesmal callose synthesis, is discussed. The first step is to screen aberrant tropic responses from 3-day-old etiolated seedlings of mutants or over-expression lines of a gene along with the wild type. This preliminary screening can lead to the identification of a range of genes functioning in PAT or controlling symplasmic connectivity. The second screening involves the sorting of candidates that show altered tropic responses by affecting symplasmic connectivity. To address such candidates, the movement of a symplasmic tracer and the deposition of plasmodesmal callose were examined. This strategy would be useful to explore new candidate genes that can regulate symplasmic connectivity directly or indirectly during tropic responses and other developmental processes.
authors.affiliation: Division of Applied Life Science (BK21 plus program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University.
authors.forename: Ritesh
authors.initials: R
authors.lastname: Kumar
authors.affiliation: Division of Applied Life Science (BK21 plus program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University.
authors.forename: Shu Wei
authors.initials: SW
authors.lastname: Wu
authors.affiliation: Division of Applied Life Science (BK21 plus program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University.
authors.forename: Arya Bagus Boedi
authors.initials: AB
authors.lastname: Iswanto
authors.affiliation: Division of Applied Life Science (BK21 plus program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University.
authors.forename: Dhinesh
authors.initials: D
authors.lastname: Kumar
authors.affiliation: Biotechnology Research Institute, Chinese Academy of Agricultural Sciences.
authors.forename: Xiao
authors.initials: X
authors.lastname: Han
authors.affiliation: Division of Applied Life Science (BK21 plus program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University; kimjaeyean@gmail.com.
authors.forename: Jae-Yean
authors.initials: JY
authors.lastname: Kim
mesh_terms: D001692:Biological Transport; D018522:Gravitropism / Q000502:physiology*; D007210:Indoleacetic Acids / Q000378:metabolism*; D008027:Light; D018524:Phototropism / Q000502:physiology*
chemical_list: D007210:Indoleacetic Acids