The association of complementary ribonucleic acids can be strongly increased without lowering Arrhenius activation energies or significantly altering structures.
The association rates of complementary nucleic acids can be increased by 2-3 orders of magnitude in vitro by cellular proteins and low molecular weight compounds including cetyltrimethylammonium bromide (CTAB). In this work, we provide experimental evidence that the CTAB-mediated enhancement of RNA-RNA annealing by approximately 3 orders of magnitude is due to a favorable activation entropy (DeltaS) and not due to a decrease of the Arrhenius activation energy (Ea) nor to major structural changes of the RNA. Two alternative models for the CTAB-facilitated RNA-RNA annealing will be discussed. First, CTAB could form a positively charged liquid matrix which could steer complementary RNA molecules and thereby increase their collision frequency and annealing rate. Second, increased annealing rates could be explained by stabilization of a non-base-specific precomplex of both complementary RNA molecules in solution.
Nedbal
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Forschungsschwerpunkt Angewandte Tumorvirologie, Deutsches Krebsforschungszentrum, Heidelberg, Germany.
Homann
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Sczakiel
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D000077286:Cetrimonium; D002593:Cetrimonium Compounds / Q000737:chemistry; D002942:Circular Dichroism; D015497:HIV-1 / Q000235:genetics; D034441:Heterogeneous-Nuclear Ribonucleoproteins; D008956:Models, Chemical; D009691:Nucleic Acid Denaturation; D012332:RNA, Heterogeneous Nuclear / Q000737:chemistry* / Q000378:metabolism; D012367:RNA, Viral / Q000737:chemistry / Q000378:metabolism; D012261:Ribonucleoproteins / Q000737:chemistry* / Q000378:metabolism; D013816:Thermodynamics
D002593:Cetrimonium Compounds; D034441:Heterogeneous-Nuclear Ribonucleoproteins; D012332:RNA, Heterogeneous Nuclear; D012367:RNA, Viral; D012261:Ribonucleoproteins; D000077286:Cetrimonium