Nucleolin N- and C-terminal domains are involved in protein-protein interaction, whereas the central domain is involved in specific interactions with nucleic acids. Nucleolin exhibits autodegradation, DNA and RNA helicase activities, and DNA-dependent ATPase activity. Nucleolin′s multiple activities may be regulated by proteolysis and methylation. It also interacts with telomerase andthis interaction is critical for the nucleolar localization of telomerase. Nucleolin might function as a cell surface receptor for lipoproteins, viruses, extracellular matrix, growth factors and other molecules.
