Nucleic acid binding properties of recombinant Zn2 HIV-1 nucleocapsid protein are modulated by COOH-terminal processing.

The nucleocapsid protein (NC) of all animal retroviruses is the major structural protein of the core ribonucleoprotein complex, bound to genomic RNA in mature virions. In a previous report, we showed that recombinant NC protein from HIV-1, a 71-amino-acid protein (NC71), is apparently able to form two types of protein-nucleic acid complexes under low [NaCl], pH 8.3 and 25 degrees C. These appeared to differ in occluded apparent site size, napp,...