Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 1994 Dec 9;269(49):30994-8.

The nucleic acid binding activity of nucleolar protein B23.1 resides in its carboxyl-terminal end

Affiliations
  • PMID: 7527039
Free article

The nucleic acid binding activity of nucleolar protein B23.1 resides in its carboxyl-terminal end

D Wang et al. J Biol Chem. .
Free article

Abstract

Protein B23 is a major nucleolar phosphoprotein proposed to be a ribosome assembly factor. Protein B23 exists as two isoforms, B23.1 and B23.2, differing only in their carboxyl-terminal sequences. The interaction of recombinantly produced B23 isoforms with double-stranded DNA was studied using gel retardation and nitrocellulose filter disk assays. Protein B23.1 bound saturably to radiolabeled plasmid DNA. By competition assays protein B23.1 was also capable of binding RNA and single-stranded DNA. On the other hand, protein B23.2, the shorter of the two isoforms, was not capable of binding double-stranded DNA. The latter result suggested that the carboxyl-terminal end of B23.1 is essential for DNA binding activity. This was confirmed by partial digestion experiments using staphylococcal V8 protease which showed that a 5-kDa fragment, containing the carboxyl-terminal end of protein B23.1 retained DNA binding activity similar to that of the parent molecule. In contrast, a 19-kDa fragment from the amino-terminal half of B23.1 did not bind DNA. The sequence of the carboxyl-terminal 68 amino acids comprising the 5-kDa fragment showed little, if any, similarity to other proteins, suggesting that this segment contains a previously undiscovered nucleic acid binding motif.

PubMed Disclaimer

Similar articles

Cited by

Publication types

LinkOut - more resources