Author/Editor		Barborič, Matjaž; Taube, Ran; Nekrep, Nada; Fujinaga, Koh; Peterlin, Matija B
Title		Binding of Tat to TAR and recruitment of positive transcription elongation factor b occur independently in bovine immunodeficiency virus
Type		članek
Source		J Virol
Vol. and No.		Letnik 74, št. 13
Publication year		2000
Volume		str. 6039-44
Language		eng
Abstract		Transcriptional transactivators (Tat) from many lentiviruses interact with their cognate transactivation response RNA structures (TAR) to increase rates of elongation rather than initiation of transcription. For several of them, the complex of Tat and a species-specific cyclin T1 must be formed before the binding to TAR can occur with high affinity and specificity. In sharp contrast, Tat from the bovine immunodeficiency virus (BIV) binds to its TAR without the help of the cyclin T1. This binding depends on the upper stem and 5' bulge, but not the central loop in TAR. Moreover, cyclins T1 from different species can mediate effects of this Tat in cells. Unlike the situation with other lentiviruses, Tat transactivation can be rescued simply by linking a heterologous promoter to TA in permissive cells. Thus, lentiviruses have evolved different strategies to recruit Tat and the positive transcription elongation factor b to their promoters, and interactions between Tat and TAR are independent from those between Tat and the cyclin T1 in BIV.
Descriptors		GENE PRODUCTS, TAT IMMUNODEFICIENCY VIRUS, BOVINE PROTEIN-SERINE-THREONINE KINASES RNA, VIRAL TRANS-ACTIVATION (GENETICS) SPECIES SPECIFICITY CATTLE COS CELLS CULTURE MEDIA, SERUM-FREE CYCLINS HELA CELLS PROTEIN BINDING DOGS