Matches in SemOpenAlex for { <https://semopenalex.org/work/W2005243325> ?p ?o ?g. }
- W2005243325 endingPage "617" @default.
- W2005243325 startingPage "591" @default.
- W2005243325 abstract "Abstract The synthesis of milligram quantities of lariat RNAs 1, 2, 5‐7 and their cyclic analogs 3 and 4 , modelling the lariat formed at the penultimate step of ligation of Group II and Nuclear mRNA introns in the Splicing reaction, have been achieved for the first time. These syntheses are highlighted by unique employment of various orthogonal protecting groups using phosphotriester and phosphoramidite chemistry. Some of the lariat‐RNAs have been found to undergo site specific self‐cleavage reaction to give an acyclic branched‐RNA with 2′,3′‐cyclic phosphate and a 5′‐hydroxyl termini, which is reminiscent of the products formed in some catalytic RNAs. These lariat‐RNAs are much smaller than the natural catalytic RNAs such as the hammerhead ribozyme (k =1 min −1 at 37°C), and their rates of the self‐cleavage is also much slower (k = 0.25×10 −4 min −1 for lariat hexamer 5 , and 0.16×10 −3 min −1 for lariat heptamer 6 at 22°C). We have shown that the trinucleotidyl loop in the tetrameric 1 and pentameric 2 lariat‐RNAs is completely stable whereas the tetranucleotidyl or pentanucleotidyl loop in the hexameric 5 or heptameric 6 lariat‐RNA does indeed have the required local and global conformation promoting the self‐cleavage while the simple 2′5′ or 3′5′‐linked cyclic RNAs, 3 and 4 , respectively, are completely stable and their structures are considerably different from the self‐cleaving lariat‐RNAs such as 5 or 6 . The unique 3′‐ethylphosphate function at the branch‐point in 7 , mimicking the 3′‐tail of the lariat‐hexamer 5 , is the key structural feature that orchestrates its self‐cleavage reaction (k = 0.15×10 −4 min −1 at 19°C) compared to the stable 2′5′‐linked cyclic RNA 3 . The detailed conformational features of the self‐cleaving lariat‐RNAs 5, 6 and 7 by 500 MHz NMR spectroscopy and molecular dynamics simulations in the aqueous environment has been reviewed. A comparative study of the temperature dependence of the N°S equilibrium for the lariat tetramer 7 and the 2′5′‐linked cyclic tetramer 3 shows that the A 1 residue in 7 is in 92% S‐type conformation at 20°C, whereas it is only in 55% S in 3 with a 3′‐hydroxyl group. This displacement of the N°S pseudorotational equilibrium toward the S geometry is due to the enhanced gauche effect of the 3′‐OPO 3 Et − group at the branch‐point adenosine in 7 compared to 3′‐OH group in 3 . This 3′‐OPO 3 Et − group promoted stabilisation of the S geometry at the branch‐point by ΔH = 4 kcal.mol −1 in 7 is contributing to the conformational driving force promoting its unique self‐cleavage reaction. The comparison of ΔH and ΔS of the N°S pseudorotational equilibria in 7 and 3 clearly shows the remarkable effect of the 3′‐ethylphosphate group in 7 in being able to dictate the conformational changes from the sugar moiety of the branch‐point adenosine to the entire molecule (conformational transmission). Thus the S conformation in A 1 , U 2 and C 6 sugar moieties is clearly thermodynamically more stabilised while it is considerably destabilised in G 3 owing to the 3′‐ethylphosphate group in 7 compared to 3 . It is interesting to note that the magnitude of enthalpy and entropy for the North to South transition of the A 1 sugar in 7 is comparable to the enthalpy and entropy of transition between the A‐ and B‐form of the lariat hexamer 5 . This self‐cleaving tetrameric lariat‐RNA 7 is the smallest RNA molecule hitherto known to undergo the self‐cleavage reaction and hence it is the simplest model of the active cleavage site of the natural self‐cleaving catalytic RNA." @default.
- W2005243325 created "2016-06-24" @default.
- W2005243325 creator A5007738439 @default.
- W2005243325 creator A5014896436 @default.
- W2005243325 creator A5037692544 @default.
- W2005243325 creator A5038084349 @default.
- W2005243325 creator A5058088923 @default.
- W2005243325 creator A5068711541 @default.
- W2005243325 creator A5078187729 @default.
- W2005243325 creator A5083487524 @default.
- W2005243325 creator A5089246623 @default.
- W2005243325 date "1994-01-01" @default.
- W2005243325 modified "2023-09-26" @default.
- W2005243325 title "The Synthesis of Lariat-RNAs and their Conformational Analysis by NMR Spectroscopy: The Study of their Unique Self-Cleavage Reaction Modelling Some Catalytic RNAs (Ribozymes)" @default.
- W2005243325 cites W1502906266 @default.
- W2005243325 cites W1505196920 @default.
- W2005243325 cites W1529847153 @default.
- W2005243325 cites W1591323727 @default.
- W2005243325 cites W1965714483 @default.
- W2005243325 cites W1966347067 @default.
- W2005243325 cites W1966708748 @default.
- W2005243325 cites W1968366025 @default.
- W2005243325 cites W1971347229 @default.
- W2005243325 cites W1974549571 @default.
- W2005243325 cites W1976027096 @default.
- W2005243325 cites W1976499671 @default.
- W2005243325 cites W1978925476 @default.
- W2005243325 cites W1978945010 @default.
- W2005243325 cites W1979351853 @default.
- W2005243325 cites W1980831280 @default.
- W2005243325 cites W1984235441 @default.
- W2005243325 cites W1986232581 @default.
- W2005243325 cites W1987867220 @default.
- W2005243325 cites W1995478437 @default.
- W2005243325 cites W1999084954 @default.
- W2005243325 cites W2004112086 @default.
- W2005243325 cites W2006374598 @default.
- W2005243325 cites W2008145887 @default.
- W2005243325 cites W2009103135 @default.
- W2005243325 cites W2011770181 @default.
- W2005243325 cites W2012959241 @default.
- W2005243325 cites W2014508207 @default.
- W2005243325 cites W2024973512 @default.
- W2005243325 cites W2025800179 @default.
- W2005243325 cites W2025948411 @default.
- W2005243325 cites W2026167708 @default.
- W2005243325 cites W2028828716 @default.
- W2005243325 cites W2032947585 @default.
- W2005243325 cites W2033727746 @default.
- W2005243325 cites W2035067877 @default.
- W2005243325 cites W2037786686 @default.
- W2005243325 cites W2043015313 @default.
- W2005243325 cites W2043354496 @default.
- W2005243325 cites W2049857490 @default.
- W2005243325 cites W2064344335 @default.
- W2005243325 cites W2068890237 @default.
- W2005243325 cites W2069636180 @default.
- W2005243325 cites W2070885910 @default.
- W2005243325 cites W2073263035 @default.
- W2005243325 cites W2076083631 @default.
- W2005243325 cites W2084274557 @default.
- W2005243325 cites W2084705960 @default.
- W2005243325 cites W2087017025 @default.
- W2005243325 cites W2088259533 @default.
- W2005243325 cites W2091267480 @default.
- W2005243325 cites W2094588396 @default.
- W2005243325 cites W2094922691 @default.
- W2005243325 cites W2095555621 @default.
- W2005243325 cites W2102971243 @default.
- W2005243325 cites W2107029002 @default.
- W2005243325 cites W2117255074 @default.
- W2005243325 cites W2122772140 @default.
- W2005243325 cites W2125792673 @default.
- W2005243325 cites W2126828866 @default.
- W2005243325 cites W2128606349 @default.
- W2005243325 cites W2140868866 @default.
- W2005243325 cites W2162392654 @default.
- W2005243325 cites W2165104520 @default.
- W2005243325 cites W2170866179 @default.
- W2005243325 cites W2327922848 @default.
- W2005243325 cites W2952981154 @default.
- W2005243325 cites W3004502745 @default.
- W2005243325 doi "https://doi.org/10.1002/bscb.19941030910" @default.
- W2005243325 hasPublicationYear "1994" @default.
- W2005243325 type Work @default.
- W2005243325 sameAs 2005243325 @default.
- W2005243325 citedByCount "2" @default.
- W2005243325 countsByYear W20052433252017 @default.
- W2005243325 crossrefType "journal-article" @default.
- W2005243325 hasAuthorship W2005243325A5007738439 @default.
- W2005243325 hasAuthorship W2005243325A5014896436 @default.
- W2005243325 hasAuthorship W2005243325A5037692544 @default.
- W2005243325 hasAuthorship W2005243325A5038084349 @default.
- W2005243325 hasAuthorship W2005243325A5058088923 @default.
- W2005243325 hasAuthorship W2005243325A5068711541 @default.
- W2005243325 hasAuthorship W2005243325A5078187729 @default.
- W2005243325 hasAuthorship W2005243325A5083487524 @default.
- W2005243325 hasAuthorship W2005243325A5089246623 @default.