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Characterization of plants expressing the human ?1,4-galactosyltrasferase gene.

ABSTRACT: Modification of the plant N-glycosylation pathway towards human type structures is an important strategy to implement plants as expression systems for therapeutic proteins. Nevertheless, relatively little is known about the overall impact of non-plant glycosylation enzymes in stable transformed plants. Here, we analyzed transgenic lines (Nicotiana benthamiana and Arabidopsis thaliana) that stably express a modified version of human ?1,4-galactosyltransferase ((ST)GalT). While some transgenic plants grew normally, other lines exhibited a severe phenotype associated with stunted growth and developmental retardation. The severity of the phenotype correlated with both increased (ST)GalT mRNA and protein levels but no differences were observed between N-glycosylation profiles of plants with and without the phenotype. In contrast to non-transgenic plants, all (ST)GalT expressing plants synthesized significant amounts of incompletely processed (largely depleted of core fucose) N-glycans with up to 40% terminally galactosylated structures. While transgenic plants showed no differences in nucleotide sugar composition and cell wall monosaccharide content, alterations in the reactivity of cell wall carbohydrate epitopes associated with arabinogalactan-proteins and pectic homogalacturonan were detected in (ST)GalT expressing plants. Notably, plants with phenotypic alterations showed increased levels of hydrogen peroxide, most probably a consequence of hypersensitive reactions. Our data demonstrate that unfavorable phenotypical modifications may occur upon stable in planta expression of non-native glycosyltransferases. Such important issues need to be taken into consideration in respect to stable glycan engineering in plants.

SUBMITTER: Schneider J

PROVIDER: S-EPMC4451504 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

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Characterization of plants expressing the human β1,4-galactosyltrasferase gene.

Schneider Jeannine J Castilho Alexandra A Pabst Martin M Altmann Friedrich F Gruber Clemens C Strasser Richard R Gattinger Pia P Seifert Georg J GJ Steinkellner Herta H

Plant physiology and biochemistry : PPB 20150413

Modification of the plant N-glycosylation pathway towards human type structures is an important strategy to implement plants as expression systems for therapeutic proteins. Nevertheless, relatively little is known about the overall impact of non-plant glycosylation enzymes in stable transformed plants. Here, we analyzed transgenic lines (Nicotiana benthamiana and Arabidopsis thaliana) that stably express a modified version of human β1,4-galactosyltransferase ((ST)GalT). While some transgenic pla ...[more]

PMID: 25900423

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Dataset Information

Characterization of plants expressing the human ?1,4-galactosyltrasferase gene.

Publications

Characterization of plants expressing the human β1,4-galactosyltrasferase gene.

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