| RRC ID |
6142
|
| 著者 |
Oka T, Saito F, Shimma Y, Yoko-o T, Nomura Y, Matsuoka K, Jigami Y.
|
| タイトル |
Characterization of endoplasmic reticulum-localized UDP-D-galactose: hydroxyproline O-galactosyltransferase using synthetic peptide substrates in Arabidopsis.
|
| ジャーナル |
Plant Physiol
|
| Abstract |
We characterized peptidyl hydroxyproline (Hyp) O-galactosyltransferase (HGT), which is the initial enzyme in the arabinogalactan biosynthetic pathway. An in vitro assay of HGT activity was established using chemically synthesized fluorescent peptides as acceptor substrates and extracts from Arabidopsis (Arabidopsis thaliana) T87 cells as a source of crude enzyme. The galactose residue transferred to the peptide could be detected by high-performance liquid chromatography and matrix-assisted laser desorption-ionization time-of-flight mass spectrometry analyses. HGT required a divalent cation of manganese for maximal activity and consumed UDP-D-galactose as a sugar donor. HGT exhibited an optimal pH range of pH 7.0 to 8.0 and an optimal temperature of 35 degrees C. The favorable substrates for the activity seemed to be peptides containing two alternating imino acid residues including at least one acceptor Hyp residue, although a peptide with single Hyp residue without any other imino acids also functioned as a substrate. The results of sucrose density gradient centrifugation revealed that the cellular localization of HGT activity is identical to those of endoplasmic reticulum markers such as Sec61 and Bip, indicating that HGT is predominantly localized to the endoplasmic reticulum. To our knowledge, this is the first characterization of HGT, and the data provide evidence that arabinogalactan biosynthesis occurs in the protein transport pathway.
|
| 巻・号 |
152(1)
|
| ページ |
332-40
|
| 公開日 |
2010-1-1
|
| DOI |
10.1104/pp.109.146266
|
| PII |
pp.109.146266
|
| PMID |
19923238
|
| PMC |
PMC2799367
|
| MeSH |
Arabidopsis / cytology
Arabidopsis / enzymology*
Arabidopsis Proteins / metabolism*
Cell Line
Endoplasmic Reticulum / enzymology*
Galactosyltransferases / metabolism*
Hydrogen-Ion Concentration
Peptides / metabolism*
Temperature
|
| IF |
6.902
|
| 引用数 |
23
|
|
WOS 分野
|
PLANT SCIENCES
|
| リソース情報 |
| シロイヌナズナ / 植物培養細胞・遺伝子 |
rpc00008 |
