Send to:

Choose Destination
See comment in PubMed Commons below
Plant Physiol. 1997 Dec;115(4):1599-1607.

Phloem-Specific Expression of the Tobacco Mosaic Virus Movement Protein Alters Carbon Metabolism and Partitioning in Transgenic Potato Plants.

Author information

  • 1Department of Field Crops, Vegetables, and Genetics and the Otto Warburg Center for Agricultural Biotechnology, The Hebrew University of Jerusalem, Faculty of Agriculture, Rehovot 76100, Israel (E.A., M.H., S.W.).


The tobacco mosaic virus movement protein (TMV-MP) has pleiotropic effects when expressed in transgenic tobacco (Nicotiana tabacum) plants. In addition to its ability to increase the plasmodesmal size-exclusion limit, the TMV-MP alters carbohydrate metabolism in source leaves and dry matter partitioning between the various plant organs. In the present study the TMV-MP was expressed under the control of a phloem-specific promoter (rolC), and this system was employed to further explore the potential sites at which the TMV-MP exerts its influence over carbon metabolism and transport in transgenic potato (Solanum tuberosum) plants. Immunohistochemical analyses indicated that the TMV-MP was localized mainly to phloem parenchyma and companion cells. Starch and sucrose accumulated in source leaves of these plants to significantly higher levels compared with control potato lines. In addition, the rate of sucrose efflux from excised petioles was lower compared with control plants. Furthermore, under short-day conditions, carbon partitioning was lower to the roots and higher to tubers in rolC plants compared with controls. These results are discussed in terms of the mode(s) by which the TMV-MP exerts its influence over carbon metabolism and photoassimilate translocation.

[PubMed - as supplied by publisher]
Free PMC Article
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Write to the Help Desk