标题：Electrostatic interactions modulate the RNA-binding and transactivation specificities of the human immunodeficiency virus and simian immunodeficiency virus Tat proteins.
期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1993
卷号：90
期号：4
页码：1571-1575
DOI：10.1073/pnas.90.4.1571
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The transcriptional activating (Tat) proteins from human immunodeficiency virus and simian immunodeficiency virus are sequence-specific RNA-binding proteins. In human immunodeficiency virus Tat, a single arginine residue, flanked on each side by three to four basic amino acids, mediates specific binding to a bulge region in trans-acting responsive element (TAR) RNA. We have systematically mutated the flanking charged residues and found that, in addition to the position of the sequence-specific arginine, the particular arrangement of nonspecific electrostatic interactions is an important determinant of RNA-binding specificity and transactivation activity. These additional electrostatic contacts may help stabilize the structure of TAR RNA when bound to arginine. One critical electrostatic interaction, located two residues N-terminal to the arginine, is absent in the simian immunodeficiency virus Tat protein and accounts for the difference in promoter specificities of the human and simian immunodeficiency viral proteins.
