Open AccessHomodimeric reverse transcriptases from Rous sarcoma virus mutated within the polymerase or RNase H active site of one subunit are active
Author(s) -
Werner Susanne,
Wöhrl Birgitta M.
Publication year - 2000
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1046/j.1432-1327.2000.01530.x
Subject(s) - rnase h , polymerase , protein subunit , rnase p , rous sarcoma virus , microbiology and biotechnology , reverse transcriptase , active site , biology , specificity factor , rnase mrp , enzyme , biochemistry , chemistry , rna dependent rna polymerase , rna , gene
Heterodimeric reverse transcriptase (RT) αβ from Rous sarcoma virus (RSV) possesses an asymmetric subunit organization with the polymerase and RNase H active sites localized in the α subunit. To determine whether homodimeric RSV RTs α (63 kDa) or β (95 kDa) assume α subunit organization similar to that of the heterodimer, an essential aspartic acid residue was mutated in the active site of either the polymerase (Asp181 > Asn) or the RNase H (Asp505 > Asn). Homodimeric α or β RT consisting of one wild‐type and one mutated subunit exhibit polymerase or RNase H activity, respectively, whereas the corresponding doubly mutated enzymes are inactive, indicating that the catalytic sites of the polymerase and RNase H domains are formed by only one subunit of the homodimer.