Functional genomic analysis of Arabidopsis thaliana glycoside hydrolase family 35

Ahn, Young Ock; Zheng, Mao; Bevan, David R.; Esen, Asım; Shiu, Shin-Han; Benson, Jonas; Peng, Hsiao Ping; Miller, Joseph T.; Cheng, Chi Lien; Poulton, Jonathan E.; Shih, Ming Che

doi:10.1016/j.phytochem.2007.03.021

Cited by 83 publications

(82 citation statements)

References 120 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1, B and G) could be due to one or more of the other 17 members of family 35 of glycosyl hydrolases (Ahn et al, 2007). A rice ortholog of AtBGAL8 had activity against both xyloglucan and galactans (Kaneko and Kobayashi, 2003).…”

Section: Insertions Inmentioning

confidence: 99%

AtBGAL10 Is the Main Xyloglucan β-Galactosidase in Arabidopsis, and Its Absence Results in Unusual Xyloglucan Subunits and Growth Defects

et al. 2012

View full text Add to dashboard Cite

In growing cells, xyloglucan is thought to connect cellulose microfibrils and regulate their separation during wall extension. In Arabidopsis (Arabidopsis thaliana), a significant proportion of xyloglucan side chains contain b-galactose linked to a-xylose at O2. In this work, we identified AtBGAL10 (At5g63810) as the gene responsible for the majority of b-galactosidase activity against xyloglucan. Xyloglucan from bgal10 insertional mutants was found to contain a large proportion of unusual subunits, such as GLG and GLLG. These subunits were not detected in a bgal10 xyl1 double mutant, deficient in both b-galactosidase and a-xylosidase. Xyloglucan from bgal10 xyl1 plants was enriched instead in XXLG/XLXG and XLLG subunits. In both cases, changes in xyloglucan composition were larger in the endoglucanase-accessible fraction. These results suggest that glycosidases acting on nonreducing ends digest large amounts of xyloglucan in wild-type plants, while plants deficient in any of these activities accumulate partly digested subunits. In both bgal10 and bgal10 xyl1, siliques and sepals were shorter, a phenotype that could be explained by an excess of nonreducing ends leading to a reinforced xyloglucan network. Additionally, AtBGAL10 expression was examined with a promoter-reporter construct. Expression was high in many cell types undergoing wall extension or remodeling, such as young stems, abscission zones, or developing vasculature, showing good correlation with a-xylosidase expression.

show abstract

Section: Insertions Inmentioning

confidence: 99%

AtBGAL10 Is the Main Xyloglucan β-Galactosidase in Arabidopsis, and Its Absence Results in Unusual Xyloglucan Subunits and Growth Defects

et al. 2012

View full text Add to dashboard Cite

show abstract

“…org; Coutinho and Henrissat, 2006) includes MUM2 as a member of glycosyl hydrolase Family 35 b-galactosidases (Ahn et al, 2007). Members of this family are found in eukaryotes and prokaryotes, and there are 18 members in Arabidopsis.…”

Section: Mum2 Encodes a Putative B-galactosidasementioning

confidence: 99%

“…However, the in vivo target of MUM2 remains to be determined; previous studies have revealed that the substrate specificities of plant b-galactosidases can vary widely, indicating functional diversity in their activity. (Ahn et al, 2007). Furthermore, b-galactosidases isolated from nasturtium (Tropaeolum majus) cotyledons (Edwards et al, 1988) and Copaifera langsdorffii (de Alcantara et al, 1999) show activity toward the b-D-Gal-(1/2)-a-D-xylose side chains of xyloglucan but show little or no activity toward pectic b-D-…”

Section: Potential Targets For the Mum2 Enzyme In Mucilagementioning

confidence: 99%

The Arabidopsis MUM2 Gene Encodes a β-Galactosidase Required for the Production of Seed Coat Mucilage with Correct Hydration Properties

et al. 2007

View full text Add to dashboard Cite

Seed coat development in Arabidopsis thaliana involves a complex pathway where cells of the outer integument differentiate into a highly specialized cell type after fertilization. One aspect of this developmental process involves the secretion of a large amount of pectinaceous mucilage into the apoplast. When the mature seed coat is exposed to water, this mucilage expands to break the primary cell wall and encapsulate the seed. The mucilage-modified2 (mum2) mutant is characterized by a failure to extrude mucilage on hydration, although mucilage is produced as normal during development. The defect in mum2 appears to reside in the mucilage itself, as mucilage fails to expand even when the barrier of the primary cell wall is removed. We have cloned the MUM2 gene and expressed recombinant MUM2 protein, which has b-galactosidase activity. Biochemical analysis of the mum2 mucilage reveals alterations in pectins that are consistent with a defect in b-galactosidase activity, and we have demonstrated that MUM2 is localized to the cell wall. We propose that MUM2 is involved in modifying mucilage to allow it to expand upon hydration, establishing a link between the galactosyl side-chain structure of pectin and its physical properties.

show abstract

“…-Galactosidases are encoded by multigene families in plants (e.g. Smith and Gross 2000;Esteban et al 2005;Mwaniki et al 2005;Tateishi et al 2005Tateishi et al , 2007Ahn et al 2007), with speciWc members involved in speciWc developmental processes. In tomato, a family of sevengalactosidases exhibit diVerential expression in developing and ripening fruit (Smith and Gross 2000).…”

Section: Introductionmentioning

confidence: 99%

Galactose metabolism in cell walls of opening and senescing petunia petals

O’Donoghue

Somerfield

Watson

et al. 2008

Planta

View full text Add to dashboard Cite

Galactose was the major non-cellulosic neutral sugar present in the cell walls of 'Mitchell' petunia (Petunia axillaris x P. axillaris x P. hybrida) flower petals. Over the 24 h period associated with flower opening, there was a doubling of the galactose content of polymers strongly associated with cellulose and insoluble in strong alkali ('residual' fraction). By two days after flower opening, the galactose content of both the residual fraction and a Na(2)CO(3)-soluble pectin-rich cell wall fraction had sharply decreased, and continued to decline as flowers began to wilt. In contrast, amounts of other neutral sugars showed little change over this time, and depolymerisation of pectins and hemicelluloses was barely detectable throughout petal development. Size exclusion chromatography of Na(2)CO(3)-soluble pectins showed that there was a loss of neutral sugar relative to uronic acid content, consistent with a substantial loss of galactose from rhamnogalacturonan-I-type pectin. beta-Galactosidase activity (EC 3.2.1.23) increased at bud opening, and remained high through to petal senescence. Two cDNAs encoding beta-galactosidase were isolated from a mixed stage petal library. Both deduced proteins are beta-galactosidases of Glycosyl Hydrolase Family 35, possessing lectin-like sugar-binding domains at their carboxyl terminus. PhBGAL1 was expressed at relatively high levels only during flower opening, while PhBGAL2 mRNA accumulation occurred at lower levels in mature and senescent petals. The data suggest that metabolism of cell wall-associated polymeric galactose is the major feature of both the opening and senescence of 'Mitchell' petunia flower petals.

show abstract

Functional genomic analysis of Arabidopsis thaliana glycoside hydrolase family 35

Cited by 83 publications

References 120 publications

AtBGAL10 Is the Main Xyloglucan β-Galactosidase in Arabidopsis, and Its Absence Results in Unusual Xyloglucan Subunits and Growth Defects

AtBGAL10 Is the Main Xyloglucan β-Galactosidase in Arabidopsis, and Its Absence Results in Unusual Xyloglucan Subunits and Growth Defects

The Arabidopsis MUM2 Gene Encodes a β-Galactosidase Required for the Production of Seed Coat Mucilage with Correct Hydration Properties

Galactose metabolism in cell walls of opening and senescing petunia petals

Contact Info

Product

Resources

About