Initiation of (-) strand DNA synthesis from tRNA(3Lys) on lentiviral RNAs: implications of specific HIV-1 RNA-tRNA(3Lys) interactions inhibiting primer utilization by retroviral reverse transcriptases.
Initiation of minus (-) strand DNA synthesis was examined on templates containing R, U5, and primer-binding site regions of the human immunodeficiency virus type 1 (HIV-1), feline immunodeficiency virus (FIV), and equine infectious anemia virus (EIAV) genomic RNA. DNA synthesis was initiated from (i) an oligoribonucleotide complementary to the primer-binding sites, (ii) synthetic tRNA(3Lys), and (iii) natural tRNA(3Lys), by the reverse transcriptases of HIV-1, FIV, EIAV, simian immunodeficiency virus, HIV type 2 (HIV-2), Moloney murine leukemia virus, and avian myeloblastosis virus. All enzymes used an oligonucleotide on wild-type HIV-1 RNA, whereas only a limited number initiated (-) strand DNA synthesis from either tRNA(3Lys). In contrast, all enzymes supported efficient tRNA(3Lys)-primed (-) strand DNA synthesis on the genomes of FIV and EIAV. This may be in part attributable to the observation that the U5-inverted repeat stem-loop of the EIAV and FIV genomes lacks an A-rich loop shown with HIV-1 to interact with the U-rich tRNA anticodon loop. Deletion of this loop in HIV-1 RNA, or disrupting a critical loop-loop complex by tRNA(3Lys) extended by 9 nt, restored synthesis of HIV-1 (-) strand DNA from primer tRNA(3Lys) by all enzymes. Thus, divergent evolution of lentiviruses may have resulted in different mechanisms to use the same host tRNA for initiation of reverse transcription.
Arts
E J
EJ
Division of Infectious Diseases, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA.
Stetor
S R
SR
Li
X
X
Rausch
J W
JW
Howard
K J
KJ
Ehresmann
B
B
North
T W
TW
Wöhrl
B M
BM
Goody
R S
RS
Wainberg
M A
MA
Grice
S F
SF
D000818:Animals; D001483:Base Sequence; D002415:Cats; D004279:DNA, Viral / Q000096:biosynthesis*; D016679:Genome, Viral; D015497:HIV-1 / Q000235:genetics / Q000378:metabolism*; D006736:Horses; D006801:Humans; D004860:Infectious Anemia Virus, Equine / Q000235:genetics / Q000378:metabolism*; D007700:Kinetics; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D012346:RNA, Transfer, Amino Acyl / Q000737:chemistry / Q000378:metabolism*; D012367:RNA, Viral / Q000737:chemistry / Q000378:metabolism*; D012194:RNA-Directed DNA Polymerase / Q000378:metabolism*; D015302:Simian Immunodeficiency Virus / Q000235:genetics / Q000378:metabolism*; D013698:Templates, Genetic
D004279:DNA, Viral; D012346:RNA, Transfer, Amino Acyl; D012367:RNA, Viral; D012194:RNA-Directed DNA Polymerase