Sucrose transporter plays a role in phloem loading in CMV-infected melon plants that are defined as symplastic loaders

Lidor Gil, Imry Yaron, Dror Shalitin, Norbert Sauer, Robert Turgeon, Shmuel Wolf*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

41 Scopus citations

Abstract

Based on the high density of plasmodesmata interconnecting the intermediary cells and their neighboring phloem parenchyma or bundle-sheath cells, and based on the insensitivity to the sucrose transport inhibitor p- chloromercuribenzenesulfonic acid (PCMBS), cucurbits have been concluded to be symplastic loaders. In the present study, we identified and characterized the full-length sequence of sucrose transporter gene (CmSUT1) from melon (Cucumis melo L. cv. Hale's best jumbo). In vitro experiments confirmed that the identified gene product has sucrose transporter activity in baker's yeast. Healthy and cucumber mosaic virus (CMV)-infected melon plants were employed to examine sucrose transporter activity in planta. Pretreatment with PCMBS inhibited loading of newly fixed 14CO2 into minor veins of CMV-infected plants. Moreover, CMV infection caused significant increase in CmSUT1 transcripts expression, mainly in vascular bundles of minor veins, which was associated with elevated sucrose content in phloem sap collected from source-leaf petioles. We propose that cucurbit plants contain the machinery for apoplastic phloem loading and that CMV infection causes a quantitative shift in the mode by which photoassimilates are loaded into the sieve tube.

Original languageAmerican English
Pages (from-to)366-374
Number of pages9
JournalPlant Journal
Volume66
Issue number2
DOIs
StatePublished - Apr 2011

Keywords

  • Cucumis melo
  • cucumber mosaic virus
  • cucurbit
  • phloem loading
  • sucrose transporter

Fingerprint

Dive into the research topics of 'Sucrose transporter plays a role in phloem loading in CMV-infected melon plants that are defined as symplastic loaders'. Together they form a unique fingerprint.

Cite this