Identification of two nuclear N-acetylglucosamine-binding proteins.
Using neoglycoproteins, lectins that recognize different sugars, including N-acetylglucosamine residues, were previously detected in animal cell nuclei. We report herein the isolation of two N-acetylglucosamine-binding proteins from HL60 cell nuclei: i) a 22 kDa polypeptide (CBP22) with an isoelectric point of 4.5 was isolated for the first time and ii) a 70 kDa polypeptide with an isoelectric point of 7.8. This latter protein corresponds to the glucose-binding protein (CBP70) previously isolated, based on the following similarities: i) they have the same molecular mass, ii) they have the same isoelectric point, iii) they are recognized by antibodies raised against CBP70, and iv) both are lectins from the C group of Drickamer's classification. CBP70 appeared to recognize glucose and N-acetylglucosamine; however, its affinity for N-acetylglucosamine was found to be twice that for glucose. The presence in the nucleus of two nuclear N-acetylglucosamine-binding proteins and their potential ligands, such as O-N-acetylglucosamine glycoproteins, strongly argues for possible intranuclear glycoprotein-lectin interactions.
Felin
M
M
Laboratoire de Glycobiologie et Reconnaissance Cellulaire, INSERM U180, UFR Biomédicale des Saints-Pères (Université René Descartes Paris V), France.
Doyennette-Moyne
M A
MA
Hadj-Sahraoui
Y
Y
Aubery
M
M
Hubert
J
J
Sève
A P
AP
D000117:Acetylglucosamine / Q000737:chemistry* / Q000378:metabolism; D001665:Binding Sites; D002352:Carrier Proteins / Q000737:chemistry* / Q000302:isolation & purification* / Q000378:metabolism*; D002460:Cell Line; D002467:Cell Nucleus / Q000737:chemistry; D002846:Chromatography, Affinity; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D037102:Lectins / Q000145:classification / Q000378:metabolism; D007951:Leukemia, Myeloid / Q000473:pathology; D009687:Nuclear Proteins / Q000302:isolation & purification* / Q000378:metabolism; D014407:Tumor Cells, Cultured
D002352:Carrier Proteins; D037102:Lectins; D009687:Nuclear Proteins; D000117:Acetylglucosamine