Open AccessEndogenous lectins from cultured cells: nuclear localization of carbohydrate-binding protein 35 in proliferating 3T3 fibroblasts.
Author(s) -
Ioannis K. Moutsatsos,
Margaret Wade,
Melvin Schindler,
John L. Wang
Publication year - 1987
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.84.18.6452
Subject(s) - 3t3 cells , biology , staining , cell cycle , population , microbiology and biotechnology , cell nucleus , lectin , cell , nuclear protein , antiserum , immunofluorescence , nucleus , cell culture , antibody , biochemistry , immunology , transfection , gene , genetics , demography , sociology , transcription factor
Proliferating 3T3 mouse fibroblasts contain higher levels of the lectin carbohydrate-binding protein 35 (CBP35) than do quiescent cultures of the same cells. An immunofluorescence study was carried out with a rabbit antiserum directed against CBP35 to map the cellular fluorescence distribution in a large population of cells under different growth conditions. This cytometric analysis showed that the lectin is predominantly localized in the nucleus of the proliferating cells. In quiescent 3T3 cultures, the majority of the cells lost their nuclear staining and underwent a general decrease in the overall fluorescence intensity. Stimulation of serum-starved quiescent 3T3 cells by the addition of serum resulted in an increase in the level of CBP35. The percentage of cells showing distinct punctate intranuclear staining reached a maximum at about the same time as the onset of the first S-phase of the cell cycle. All of these results suggest that CBP35 may be a protein whose presence in the nucleus, in discrete punctate distribution, is coordinated with the proliferation state of the cell.