C23 interacts with B23, a putative nucleolar-localization-signal-binding protein.

Y P Li; R K Busch; B C Valdez; H Busch

doi:10.1111/j.1432-1033.1996.0153n.x

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C23 interacts with B23, a putative nucleolar-localization-signal-binding protein.

Y P Li·R K Busch·B C Valdez·H Busch

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Abstract

The human protein C23 (nucleolin) is a major nucleolar protein. Its interactions with other proteins were studied with the two-hybrid system which identified nucleolar protein B23 (nucleophosmin) as being associated with C23. Both proteins were co-immunoprecipitated from HeLa cell nuclear extract by either monoclonal anti-C23 or monoclonal anti-B23. Binding studies utilizing deletion mutants indicated that the binding of C23 and B23 involves specific motifs. In addition to an approximately 46-amino-acid-binding domain in B23 (amino acids 194-239), amino acids 540-628 of C23 were required for binding; this region of C23 is required for the nucleolar localization. In addition, nucleolar protein p120 was also found to be co-immunoprecipitated with B23. A fragment of p120 containing a functional nucleolar localization signal bound to the truncated binding domain of B23, as did C23. These results suggest that the interaction of C23 and B23 may represent a nucleolar-targeting mechanism in which B23 acts as a nucleolar-localization signal-binding protein.

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Glutathione Transferase HeLa Cells Humans Nuclear Proteins Nucleolus Organizer Region Nucleophosmin Phosphoproteins Precipitin Tests Protein Binding Protein Sorting Signals RNA-Binding Proteins Recombinant Fusion Proteins Saccharomyces cerevisiae Nucleolin Journal Article Research Support, Non-U.S. Gov't

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Y P Li, R K Busch, B C Valdez, H Busch. 1996-04-01. C23 interacts with B23, a putative nucleolar-localization-signal-binding protein.. https://doi.org/10.1111/j.1432-1033.1996.0153n.x

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