Soluble Rous Sarcoma Virus reverse transcriptases α, αβ, and β purified from insect cells are processive DNA polymerases that lack an RNase H 3' → 5' directed processing activity

Title data

Werner, Susanne ; Wöhrl, Birgitta:
Soluble Rous Sarcoma Virus reverse transcriptases α, αβ, and β purified from insect cells are processive DNA polymerases that lack an RNase H 3' → 5' directed processing activity.
In: The Journal of Biological Chemistry. Vol. 274 (1999) Issue 37 . - pp. 26329-26336.
ISSN 1083-351X
DOI: https://doi.org/10.1074/jbc.274.37.26329

Abstract in another language

Reverse transcriptase (RT) isolated from Rous sarcoma virus (RSV) consists of heterodimeric RTαβ, RTα, and RTβ. The α subunit (63 kDa) contains an N-terminal polymerase and a C-terminal RNase H domain. The N terminus of β (95 kDa) corresponds to α with the integrase domain attached to the C terminus (32 kDa). We have constructed baculoviruses expressing the genes for α or β or the entire pol (99 kDa). Infection of insect cells with recombinant virus yielded highly active and soluble RSV RT enzymes that could be purified to >90% homogeneity. HPLC gel filtration showed that α is a dimeric enzyme that can be partially monomerized upon the addition of 45% Me₂SO. DNA synthesis on DNA-DNA and DNA-RNA primer-templates in the presence of competitor substrates revealed that αβ and β as well as α are processive polymerases. However, the affinity of β and αβ for primer-template substrates appears to be higher than that of α. All RSV enzymes investigated have the potential to displace RNA-RNA duplexes more efficiently than human immunodeficiency virus type 1 RT. Unlike human immunodeficiency virus type 1 RT, RSV RTs can catalyze an initial RNase H endonucleolytic cleavage of the RNA template but not a 3′ → 5′ directed processing activity.

Further data

Item Type:	Article in a journal
Refereed:	Yes
Institutions of the University:	Faculties > Faculty of Biology, Chemistry and Earth Sciences Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry > Chair Biopolymers Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry > Chair Biopolymers > Lehrstuhl Biopolymere - Apl. Prof. Dr. Birgitta Wöhrl
Result of work at the UBT:	No
DDC Subjects:	500 Science > 540 Chemistry 500 Science > 570 Life sciences, biology
Date Deposited:	17 May 2019 07:55
Last Modified:	17 May 2019 07:55
URI:	https://eref.uni-bayreuth.de/id/eprint/48978