Identification of a mannitol transporter, AgMaT1, in celery phloem.
A celery petiole phloem cDNA library was constructed and used to identify a cDNA that gives Saccharomyces cerevisiae cells the ability to grow on mannitol and transport radiolabeled mannitol in a manner consistent with a proton symport mechanism. This cDNA was named AgMaT1 (Apium graveolens mannitol transporter 1). The expression profile in source leaves and phloem was in agreement with a role for mannitol in phloem loading in celery. The identification in eukaryotes of a mannitol transporter is important because mannitol is not only a primary photosynthetic product in species such as celery but is also considered a compatible solute and antioxidant implicated in resistance to biotic and abiotic stress.
Laboratoire de Physiologie et Biochimie Végétales, Centre National de la Recherche Scientifique Unité Mixte de Recherches 6161, 40 Avenue du Recteur Pineau, F-86022 Poitiers Cedex, France.
N
N
Noiraud
L
L
Maurousset
R
R
Lemoine
D000595:Amino Acid Sequence; D019661:Apiaceae / Q000378:metabolism*; D001483:Base Sequence; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D003001:Cloning, Molecular; D004926:Escherichia coli; D005786:Gene Expression Regulation; D015723:Gene Library; D008353:Mannitol / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D026901:Membrane Transport Proteins; D008969:Molecular Sequence Data; D021141:Nucleic Acid Amplification Techniques; D030781:Organisms, Genetically Modified; D010802:Phylogeny; D010940:Plant Proteins; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D017385:Sequence Homology; D013379:Substrate Specificity
C432563:AgMat1 protein, Apium graveolens; D002352:Carrier Proteins; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D010940:Plant Proteins; D008353:Mannitol