Stable expression of functional CBP70 lectin during heat shock

CBP70 is a glycoslylated lectin that interacts through either glycan-lectin or protein-protein interactions. In addition, depending on its cellular lo calization, this lectin has different partners, for example, galectin-3, an 82-kDa ligand in the nucleus, or Bcl-2 in the cytoplasm. In this study, we observed the persistence of plurilocalized lectin CBP70 after two heat-sho ck treatments conducted either under mild conditions, i.e.,, incubating the cells for 1 h at 42 degrees C then for 1, 3, 5, 7, or 9 h at 37 degrees C, or harsh conditions, i.e., incubation at 42 degrees C for 1, 2, 4, 6, 8, o r 10 h. By combining the information collected from biochemical, fluorocyto metric, confocal, and affinity-chromatography analyses, we concluded that C BP70 persisted in HL60 cells and its N-acetylglucosamine-binding sites rema ined active after all the heat-shock treatments tested. These data and the previously published findings reviewed in this report concur in supporting the hypothesis that CBP70 could function as an organizer of multimeric asse mbly, leading to the formation of various complexes in different cellular c ompartments, according to the needs of the cell. J. Cell. Biochem. 77:615-6 23, 2000. (C) 2000 Wiley-Liss, Inc.