Cloned (Comment) | Organism |
---|---|
BdTHX1, transcriptional profiling, recombinant expression of BdXTH8(amino acids 25-301), without the N-terminal signal peptide, in Pichia pastoris as a secreted protein using a Pichia pastoris signal sequence | Brachypodium distachyon |
Protein Variants | Comment | Organism |
---|---|---|
additional information | in constructed BdTHX1 RNA1 knockdown lines of Brachypodium distachyon, the expression of BdTHX1 and BdXTH8 is downregulated, and the transcript abundance of BdCSLF6 is not significantly changed. In the four lines, the expression of BdTHX1, BdCSLF6, and BdXTH8 show the same pattern in the T0, T1, and T2 generation | Brachypodium distachyon |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
cell wall | - |
Brachypodium distachyon | 5618 | - |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Brachypodium distachyon | - |
- |
- |
Source Tissue | Comment | Organism | Textmining |
---|---|---|---|
endosperm | - |
Brachypodium distachyon | - |
internode | elongating | Brachypodium distachyon | - |
leaf | - |
Brachypodium distachyon | - |
additional information | transcriptional profiling, BdXTH8, along with the other three genes in the grass-specific clade, is expressed in tissues that accumulate high amounts of MLG. BdXTH8 is highly coexpressed with the transcription factor BdTHX2 in addition to BdTHX1. BdXTH8 and BdTHX2 both have higher expression in elongating internodes and elongating leaf tissue than that in endosperm, while BdTHX1 shows expression in elongating internodes and endosperm tissues | Brachypodium distachyon | - |
seedling | - |
Brachypodium distachyon | - |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
barley (1->3,1->4)-beta-D-glucan + XXXGol | MXE activity | Brachypodium distachyon | ? | - |
? | |
additional information | the grass-specific endotransglucosylase BdXTH8 preferentially uses MLG as a substrate, but also xyloglucan. BdXTH8 does not yield hydrolysis products separable by thin-layer chromatography when acting on xyloglucan or MLG. Mixed-linkage glucan (MLG) consists of several adjacent (1,4)-linked Glc residues separated by a single (1,3)-glucosyl linkage that occurs every third or fourth residue | Brachypodium distachyon | ? | - |
- |
Subunits | Comment | Organism |
---|---|---|
? | x * 60000, recombinant secreted enzyme BdXTH8, SDS-PAGE | Brachypodium distachyon |
Synonyms | Comment | Organism |
---|---|---|
BdTHX8 | - |
Brachypodium distachyon |
grass-specific glycoside hydrolase family 16 endotransglucosylase/hydrolase | - |
Brachypodium distachyon |
MLG:xyloglucan endotransglucosylase | - |
Brachypodium distachyon |
More | cf. EC 2.4.1.207, XET | Brachypodium distachyon |
MXE | - |
Brachypodium distachyon |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
25 | - |
assay at | Brachypodium distachyon |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
5.3 | 5.4 | - |
Brachypodium distachyon |
Organism | Comment | Expression |
---|---|---|
Brachypodium distachyon | BdTHX1 likely plays an important role in MLG biosynthesis and restructuring by regulating the expression of BdCSLF6 and BdXTH8 | additional information |
General Information | Comment | Organism |
---|---|---|
evolution | BdXTH8 is a member of this grass-specific clade of GH16 genes in Brachypodium distachyon. Gene BdXTH8 encodes a grass-specific glycoside hydrolase family 16 endotransglucosylase/hydrolase. BdXTH8 is a poalean XTH that preferentially exhibits MXE (EC 2.4.1.B52), a hetero-transglycosylase activity | Brachypodium distachyon |
malfunction | Brachypodium distachyon shoots regenerated from transformed calli overexpressing BdTHX1 show an abnormal arrangement of vascular tissue and seedling-lethal phenotypes. These results indicate that the transcription factor BdTHX1 likely plays an important role in MLG biosynthesis and restructuring by regulating the expression of BdCSLF6 and BdXTH8 | Brachypodium distachyon |
metabolism | a trihelix family transcription factor is associated with key genes in mixed-linkage glucan accumulation. Brachypodium distachyon trihelix family transcription factor (BdTHX1) is highly coexpressed with the Brachypodium distachyon CSLF6 gene (BdCSLF6), which suggests that BdTHX1 is involved in the regulation of mixed-linkage glucan (MLG) biosynthesis. The gene encoding a grass-specific glycoside hydrolase family 16 endotransglucosylase/hydrolase (BdXTH8) is bound by BdTHX1. BdTHX1 directly binds to an intronic region of BdCSLF6 and also to the 3' proximal region of BdXTH8. BdTHX1 likely plays an important role in MLG biosynthesis and restructuring by regulating the expression of BdCSLF6 and BdXTH8. BdTHX1 may regulate genes related to cell wall assembly or restructuring such as BdXTH8, and misregulation of BdTHX1 is detrimental to Brachypodium distachyon development | Brachypodium distachyon |
additional information | BdXTH8 has a BdTHX1 transcription factor binding site in the 3' proximal region. BdXTH8 binding analysis with transcription factors, overview | Brachypodium distachyon |
physiological function | BdXTH8 exhibits predominantly MLG:xyloglucan endotransglucosylase activity, a hetero-transglycosylation reaction, and can thus produce MLG-xyloglucan covalent bonds. It also has a lower xyloglucan:xyloglucan endotransglucosylase activity. Mixed-linkage glucan (MLG) is a polysaccharide that is highly abundant in grass endosperm cell walls and present at lower amounts in other tissues. BdXTH8 does not exhibit appreciable cellulose:xyloglucan endotransglucosylase (CXE) activity, with either insoluble (paper) cellulose or water-soluble cellulose acetate as donor substrate. The enzyme's main role in vivo is likely to be the making and/or breaking of MLG-xyloglucan covalent bonds that stably link two hemicelluloses of the grass cell wall and thus contribute to grass cell wall assembly and/or loosening | Brachypodium distachyon |