TY - JOUR
T1 - Dissociation of long-chain duplex RNA can occur via strand displacement in vitro: Biological implications
AU - Homann, Matthias
AU - Nedbal, Wolfgang
AU - Sczakiel, Georg
N1 - Funding Information:
We thank H.zur Hausen for continuous support and interest. We also wish to cordially thank C.Hélène, J.Reinstein and R.S.Goody for stimulating suggestions and discussions, as well as P.Romby for helpful comments. This work was supported in part by the Deutsche Forschungsgemeinschaft, the European Union (HCM) and the Bundesministerium für Forschung und Technologie.
PY - 1996
Y1 - 1996
N2 - Hammerhead ribozymes with long antisense flanks (> 50 bases) have been used successfully to inhibit replication of human immunodeficiency virus type 1 (HIV-1) in living cells. To explain their increased efficacy versus antisense controls or catalytically inactive derivatives, one can consider dissociation of the ribozyme-product complex to allow a complete catalytic cycle. In this work we investigated the dissociation of a double-stranded RNA with 56 bp in vitro. Dissociation was observed in the presence of single-stranded RNA with sequence complementarity to one of the duplex strands. A displacement reaction between RNA single strands and the duplex, but not simple dissociation, was strongly suggested by the concentration dependence of this process, the influence of additional non-complementary sequences on the single strand and by the unusually low Arrhenius activation energy. The strand displacement reaction was slow in vitro at 37°C and physiological ionic strength, but was increased to k ≃ 103-104/M/s (~104-fold) at higher temperatures by cetyltrimethylammonium bromide. This compound is thought to enhance non-sequence-specific association of nucleic acids in a mechanistically similar way to that in which cellular hnRNP proteins are thought to act, indicating that strand displacement can be fast and, more importantly, could be tightly regulated in vivo.
AB - Hammerhead ribozymes with long antisense flanks (> 50 bases) have been used successfully to inhibit replication of human immunodeficiency virus type 1 (HIV-1) in living cells. To explain their increased efficacy versus antisense controls or catalytically inactive derivatives, one can consider dissociation of the ribozyme-product complex to allow a complete catalytic cycle. In this work we investigated the dissociation of a double-stranded RNA with 56 bp in vitro. Dissociation was observed in the presence of single-stranded RNA with sequence complementarity to one of the duplex strands. A displacement reaction between RNA single strands and the duplex, but not simple dissociation, was strongly suggested by the concentration dependence of this process, the influence of additional non-complementary sequences on the single strand and by the unusually low Arrhenius activation energy. The strand displacement reaction was slow in vitro at 37°C and physiological ionic strength, but was increased to k ≃ 103-104/M/s (~104-fold) at higher temperatures by cetyltrimethylammonium bromide. This compound is thought to enhance non-sequence-specific association of nucleic acids in a mechanistically similar way to that in which cellular hnRNP proteins are thought to act, indicating that strand displacement can be fast and, more importantly, could be tightly regulated in vivo.
UR - http://www.scopus.com/inward/record.url?scp=0029859509&partnerID=8YFLogxK
U2 - 10.1093/nar/24.22.4395
DO - 10.1093/nar/24.22.4395
M3 - Journal articles
C2 - 8948629
AN - SCOPUS:0029859509
SN - 0305-1048
VL - 24
SP - 4395
EP - 4400
JO - Nucleic Acids Research
JF - Nucleic Acids Research
IS - 22
ER -