Arabinoxylan Biosynthesis in Wheat. Characterization of Arabinosyltransferase Activity in Golgi Membranes

Porchia, Andrea Celia; Sørensen, Susanne O.; Scheller, Henrik Vibe

doi:10.1104/pp.003400

Cited by 62 publications

(44 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the intact mung bean membrane system, it appears that at least 25% of the incorporated Ara exists in the furanose conformation. Additionally, using UDP-l-[ 14 C]arabinopyranose and intact wheat (Triticum aestivum) microsomal or Golgi membranes, [ 14 C]arabinofuranose was incorporated into several products (Porchia et al, 2002). Together, these results suggest that upon solubilization of the microsomal membranes, an important component is lost that is essential for the conversion of arabinopyranose to arabinofuranose.…”

Section: Discussionmentioning

confidence: 56%

“…However, when an incorporation reaction, which had only been precipitated with chloroform:methanol, was heated with an SDS/dithiothreitol (DTT) loading buffer and separated by SDS-PAGE, a radiolabeled protein band at approximately 42 kD was seen (results not shown). This is likely to be the same protein as the carbohydrate-binding protein reported by Bolwell (1986) and may also be related to a reversibly arabinosylated protein observed in wheat (Porchia et al, 2002). The 42-kD protein was obviously not seen on the SEC column due to its poor solubility.…”

Section: Arabinosyltransferase Activity Using Endogenous Acceptorsmentioning

confidence: 70%

“…1B), which indicated the presence of UDP-Xyl-4-epimerase activity. The presence of epimerase activity in microsomal preparations from mung beans as well as from other plant species has been reported previously (Odzuck and Kauss, 1972;Bolwell and Northcote, 1981;Porchia et al, 2002). A number of procedures were attempted to remove this epimerase activity, such as extensive washing of the microsomal preparation and fractionation of the preparation by Suc gradients, but enough of the epimerase activity remained so that radiolabeled Xyl was present in the endogenous product (results not shown).…”

Section: Arabinosyltransferase Activity Using Endogenous Acceptorsmentioning

confidence: 99%

See 2 more Smart Citations

Solubilization of an Arabinan Arabinosyltransferase Activity from Mung Bean Hypocotyls

Nunan¹,

Scheller²

2003

Plant Physiology

Self Cite

View full text Add to dashboard Cite

The biosynthesis of polysaccharides destined for the plant cell wall and the subsequent assembly of the cell wall are poorly understood processes that are currently the focus of much research. Arabinan, a component of the pectic polysaccharide rhamnogalacturonan I, is composed of arabinosyl residues connected via various glycosidic linkages, and therefore, the biosynthesis of arabinan is likely to involve more than one arabinosyltransferase. We have studied the transfer of [ 14 C]arabinose (Ara) from UDP-l-arabinopyranose onto polysaccharides using microsomal membranes isolated from mung bean (Vigna radiata) hypocotyls. [ 14 C]arabinosyl and [ 14 C]xylosyl residues were incorporated into endogenous products due to the presence of UDP-Xyl-4-epimerase activity. Enzymatic digestion of endogenous products with endo-arabinanase released very little radiolabeled sugars, whereas digestion with arabinofuranosidase released some [ 14 C]Ara. Microsomal membranes solubilized with the detergent octyl glucoside were able to add a single [ 14 C]Ara residue onto (135)-linked ␣-l-arabino-oligosaccharide acceptors. The reaction had a pH optimum of 6.5 and a requirement for manganese ions. However, enzymatic digestion of the radiolabeled oligosaccharides with endo-arabinanase and arabinofuranosidases could not fully release the radiolabeled Ara residue, indicating that the [ 14 C]Ara residue was not a (132)-, (133)-, or (135)-linked ␣-l-arabinofuranosyl residue. Rather, mild acid treatment of the product suggested that the radiolabeled Ara residue was in a pyranose conformation, and this result was confirmed by thin-layer chromatography of radiolabeled partially methylated sugars. Using microsomal membranes separated on a discontinuous sucrose gradient, the arabinosyltransferase activity appears to be mainly localized to Golgi membranes.Pectic polysaccharides are major components of primary plant cell walls and middle lamella. Three main types of pectic polysaccharides have been identified, homogalacturonan, rhamnogalacturonan I (RG I), and rhamnogalacturonan II (RG II). RG I is composed of a backbone of alternating [34-␣-d-GalA-(132)-␣-l-Rha- (13] in which some of the rhamnose residues are substituted with complex side chains containing Ara and Gal residues. The composition and size of these side chains varies depending on the plant species, tissue type, and stage of development (O'Neill et al., 1990;Carpita and Gibeaut, 1993). In general, the arabinan side chains consist of a linear chain of (135)-linked ␣-l-arabinofuranosyl residues that may be substituted at the O-3 and/or O-2 with additional arabinofuranosyl residues (Carpita and Gibeaut, 1993;Schols and Voragen, 2002).The study of the biosynthesis of plant cell wall polysaccharides in plants is a growing field, but to date, very few genes encoding glycosyltransferases have been characterized (Edwards et al., 1999;Perrin et al., 1999;Faik et al., 2002). Notably, many different transferases must be involved in pectin biosynthesis, but until very recently, none had been isola...

show abstract

Section: Discussionmentioning

confidence: 56%

Section: Arabinosyltransferase Activity Using Endogenous Acceptorsmentioning

confidence: 70%

Section: Arabinosyltransferase Activity Using Endogenous Acceptorsmentioning

confidence: 99%

See 1 more Smart Citation

Solubilization of an Arabinan Arabinosyltransferase Activity from Mung Bean Hypocotyls

Nunan¹,

Scheller²

2003

Plant Physiology

Self Cite

View full text Add to dashboard Cite

show abstract

“…3B and Table S4). We wanted to determine whether XAX1 localizes with other previously characterized xylan synthesis enzymes in the Golgi apparatus (44). As with other members of the GT61 family, XAX1 has an N-terminal putative transmembrane domain (Fig.…”

Section: Xax1 Is a Golgi-localized Protein Specifically Expressed In mentioning

confidence: 99%

XAX1 from glycosyltransferase family 61 mediates xylosyltransfer to rice xylan

Chiniquy

Sharma

Schultink

et al. 2012

Proc. Natl. Acad. Sci. U.S.A.

177

161

View full text Add to dashboard Cite

Xylan is the second most abundant polysaccharide on Earth and represents an immense quantity of stored energy for biofuel production. Despite its importance, most of the enzymes that synthesize xylan have yet to be identified. Xylans have a backbone of β-1,4–linked xylose residues with substitutions that include α-(1→2)–linked glucuronosyl, 4- O -methyl glucuronosyl, and α-1,2- and α-1,3-arabinofuranosyl residues. The substitutions are structurally diverse and vary by taxonomy, with grass xylan representing a unique composition distinct from dicots and other monocots. To date, no enzyme has yet been identified that is specific to grass xylan synthesis. We identified a xylose-deficient loss-of-function rice mutant in Os02g22380, a putative glycosyltransferase in a grass-specific subfamily of family GT61. We designate the mutant xax1 for x ylosyl a rabinosyl substitution of x ylan 1. Enzymatic fingerprinting of xylan showed the specific absence in the mutant of a peak, which was isolated and determined by 1 H-NMR to be (β-1,4-Xyl) 4 with a β-Xyl p -(1→2)-α-Ara f -(1→3). Rice xax1 mutant plants are deficient in ferulic and coumaric acid, aromatic compounds known to be attached to arabinosyl residues in xylan substituted with xylosyl residues. The xax1 mutant plants exhibit an increased extractability of xylan and increased saccharification, probably reflecting a lower degree of diferulic cross-links. Activity assays with microsomes isolated from tobacco plants transiently expressing XAX1 demonstrated xylosyltransferase activity onto endogenous acceptors. Our results provide insight into grass xylan synthesis and how substitutions may be modified for increased saccharification for biofuel generation.

show abstract

“…Although studies have identified key enzymes that are involved in hydroxycinnamoyl-AX synthesis, including xylosyl transferase from barley (Urahara et al 2004), arabinosyl transferase from wheat (Porchia et al 2002), and feruloyl transferase from parsley, Festuca arundinacea, and rice (Meyer et al 1991;Myton and Fry 1994;Yoshida-Shimokawa et al 2001), the genes encoding these enzymes are still unknown. Using public EST databases for cereals and dicots, Mitchell et al (2007) proposed candidate genes for xylan synthase, arabinosyl transferase, feruloyl transferase, and acyltransferase, of which several genes encoding glycosyl transferase (GT) 61 family were experimentally shown to be responsible for the activity of arabinosyl transferase and xylosyl transferase (Anders et al 2012;Chiniquy et al 2012).…”

mentioning

confidence: 99%

Transcription profiling identifies candidate genes for secondary cell wall formation and hydroxycinnamoyl-arabinoxylan biosynthesis in the rice internode

Nakano

Nishikubo

Sato-Izawa

et al. 2013

Plant Biotechnology

View full text Add to dashboard Cite

Microarray analysis was used to identify candidate genes that are involved in the formation of secondary cell walls and hydroxycinnamoyl-arabinoxylan (AX) in rice. In order to identify genes involved in secondary cell wall formation, gene expression was compared between wild-type whole internodes that contain cells with thickened secondary cell walls, such as vascular and cortical fiber cells, and wild-type internode parenchyma cells without secondary cell walls. In addition, gene expression was compared between the internode parenchyma of Fukei71 (F71), a rice dwarf mutant that accumulates large amounts of hydroxycinnamoyl-AX in pith parenchyma cells, and wild-type pith parenchyma cells to identify hydroxycinnamoyl-AX-related genes. To address the significant expression of candidate genes, gene lists were prepared for the phenylpropanoid pathway, major carbon metabolism, and cell wall biosynthesis, which is a useful platform to analyze cell wall formation in rice. The data indicated that a number of rice genes are potentially associated with secondary cell wall formation, such as the up-regulation of genes encoding cellulose synthase subunit A and ferulate 5-hydroxylase in wild-type whole internodes. Similarly, for hydroxycinnamoyl-AX synthesis, the expression of several genes changed, such as the downregulation of genes encoding cinnamoyl-CoA reductase and the up-regulation of the phosphoenolpyruvate carboxykinase gene in F71 pith parenchyma.

show abstract

Arabinoxylan Biosynthesis in Wheat. Characterization of Arabinosyltransferase Activity in Golgi Membranes

Cited by 62 publications

References 43 publications

Solubilization of an Arabinan Arabinosyltransferase Activity from Mung Bean Hypocotyls

Solubilization of an Arabinan Arabinosyltransferase Activity from Mung Bean Hypocotyls

XAX1 from glycosyltransferase family 61 mediates xylosyltransfer to rice xylan

Transcription profiling identifies candidate genes for secondary cell wall formation and hydroxycinnamoyl-arabinoxylan biosynthesis in the rice internode

Contact Info

Product

Resources

About