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A dysfunctional movement protein of tobacco mosaic virus that partially modifies the plasmodesmata and limits virus spread in transgenic plants
Author(s) -
Lapidot Moshe,
Gafny Ron,
Ding Biao,
Wolf Shmuel,
Lucas William J.,
Beachy Roger N.
Publication year - 1993
Publication title -
the plant journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.058
H-Index - 269
eISSN - 1365-313X
pISSN - 0960-7412
DOI - 10.1046/j.1365-313x.1993.04060959.x
Subject(s) - tobacco mosaic virus , plasmodesma , movement protein , biology , nicotiana tabacum , tobamovirus , transgene , genetically modified crops , virus , wild type , microbiology and biotechnology , mutant , virology , gene , cell wall , botany , biochemistry , rna , coat protein
A chimeric gene encoding a dysfunctional tobacco mosaic virus (TMV) movement protein (MP) mutant lacking amino acids 3, 4 and 5 (MPΔ3–5), was expressed in transgenic Nicotiana tabacum Xanthi and Xanthi NN plants. Immunogold labeling studies of tissues from transgenic plants indicated that while wild‐type MP accumulated in the plasmodesmata, MPΔ3–5 did not. Tissue fractionation studies confirmed that only a low level of the mutant MP accumulated in the cell wall‐enriched fraction compared with the accumulation of the wild‐type MP. Dye coupling studies showed that MPΔ3–5 enabled the movement between leaf mesophyll cells of a fluorescently labeled dextran of 3 kDa, while 9.4 kDa molecules failed to move. In contrast, in transgenic plants expressing the wild‐type MP gene the 9.4 kDa probe did move from cell to cell. Seedlings from self‐fertilized transgenic plants were inoculated with TMV and observed for disease symptoms. Transgenic Xanthi NN plants that expressed the MPΔ3–5 gene developed fewer and smaller necrotic local lesions compared with control plants following inoculation with TMV. Transgenic Xanthi nn plants were delayed in the development of systemic symptoms. Inoculating the transgenic plants with TMV‐RNA, and the tobamo‐viruses TMGMV and SHMV, essentially produced the same results, i.e. inhibition of disease development. These results demonstrate that transgenic plants expressing an inactive MP can inhibit virus disease spread presumably by interfering with its cell‐to‐cell movement.