Analyses of carbohydrate binding property of lectin-chaperone calreticulin.
Biochem Biophys Res Commun
; 364(2): 332-7, 2007 Dec 14.
Article
in En
| MEDLINE
| ID: mdl-17950701
ABSTRACT
Calreticulin (CRT) is a soluble molecular chaperone of the endoplasmic reticulum. It is a lectin that promotes the folding of proteins carrying N-linked glycans. Recent investigations have revealed that glucosylated high-mannose-type glycans are employed as key elements in this process. Here, we performed quantitative analyses of the interaction of CRT with various disaccharides, including fluorine-substituted analogues using a quartz-crystal microbalance (QCM). These experiments revealed the weak affinity of 2- and 3-fluoroglucose derivatives. On the other hand, 6-fluoroglucose derivatives exhibited a significant affinity, indicating that the role of 6-position of OH is less significant for binding to CRT. We also characterized binding epitope of the Glcalpha1-3Man(alpha)Me to CRT by saturation transfer difference (STD) NMR spectroscopy. It is proposed that 2-, 3-, and 4-positions of Glc and 3-, 4-, and 6-positions of Man are in close contact with CRT binding pocket, while 6-position of Glc and 2-position of Man are not. These finding are in excellent agreement with our QCM experiment.
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Collection:
01-internacional
Database:
MEDLINE
Main subject:
Molecular Chaperones
/
Calreticulin
/
Lectins
Limits:
Animals
/
Humans
Language:
En
Journal:
Biochem Biophys Res Commun
Year:
2007
Document type:
Article
Affiliation country: