tailieunhanh - Báo cáo khoa học: N-glycosylation influences the structure and self-association abilities of recombinant nucleolin

Nucleolin is a major nucleolar protein involved in fundamental processes of ribosome biogenesis, regulation of cell proliferation and growth. Nucleolin is known to shuttle between nucleus, cytoplasm and cell surface. We have pre-viously found that nucleolin undergoes complex N- and O-glycosylations in extra-nuclear isoforms. | IFEBS Journal N-glycosylation influences the structure and self-association abilities of recombinant nucleolin Marie-Estelle Losfeld1 2 3 Arnaud Leroy1 2 3 4 Bernadette Coddeville1 2 3 Mathieu Carpentier1 2 3 Joel Mazurier1 2 3 and Dominique Legrand1 2 3 1 Univ Lille Nord de France Lille France 2 USTL UGSF Villeneuve d Ascq France 3 CNRS UMR Villeneuve d Ascq France 4 EA 4529 Laboratoire de Biochimie appliquee Faculte de Pharmacie Universite Paris XI Chatenay-Malabry France Keywords glycans glycosylation intermolecular interactions nucleolin Correspondence D. Legrand Unite de Glycobiologie Structurale et Fonctionnelle UMR CNRS 8576 IFR 147 Universite des Sciences et Technologies de Lille 59655 Villeneuve d Ascq Cedex France Fax 33 3 20436555 Tel 33 3 20434430 E-mail Received 28 January 2011 revised 5 April 2011 accepted 12 May 2011 doi Nucleolin is a major nucleolar protein involved in fundamental processes of ribosome biogenesis regulation of cell proliferation and growth. Nucleolin is known to shuttle between nucleus cytoplasm and cell surface. We have previously found that nucleolin undergoes complex N- and O-glycosylations in extra-nuclear isoforms. We found that surface nucleolin is exclusively glycosylated and that N-glycosylation is required for its expression on the cells. Interestingly the two N-glycans are located in the RNA-binding domains RBDs which participate in the self-association properties of nucleolin. We hypothesized that the occupancy of RBDs by N-glycans plays a role in these self-association properties. Here owing to the inability to quantitatively produce full-size nucleolin we expressed four N-glycosylation nucleolin variants lacking the N-terminal acidic domain in a baculovirus insect cell system. As assessed by heptafluorobutyrate derivatization and mass spectrometry this strategy allowed the production of proteins bearing or not paucimannosidic-type glycans on either one .