Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2000-3-23
pubmed:abstractText
Retroviruses employ -1 translational frameshifting to regulate the relative concentrations of structural and non-structural proteins critical to the viral life cycle. The 1.6 A crystal structure of the -1 frameshifting pseudoknot from beet western yellows virus reveals, in addition to Watson-Crick base-pairing, many loop-stem RNA tertiary structural interactions and a bound Na(+). Investigation of the thermodynamics of unfolding of the beet western yellows virus pseudoknot reveals strongly pH-dependent loop-stem tertiary structural interactions which stabilize the molecule, contributing a net of DeltaH approximately -30 kcal mol(-1) and DeltaG degrees (37) of -3.3 kcal mol(-1) to a total DeltaH and DeltaG degrees (37) of -121 and -16 kcal mol(-1), respectively, at pH 6.0, 0.5 M K(+) by DSC. Characterization of mutant RNAs supports the presence of a C8(+).G12-C26 loop 1-stem 2 base-triple (pK(a)=6.8), protonation of which contributes nearly -3.5 kcal mol(-1) in net stability in the presence of a wild-type loop 2. Substitution of the nucleotides in loop 2 with uridine bases, which would eliminate the minor groove triplex, destroys pseudoknot formation. An examination of the dependence of the monovalent ion and type on melting profiles suggests that tertiary structure unfolding occurs in a manner quantitatively consistent with previous studies on the stabilizing effects of K(+), NH(4)(+) and Na(+) on other simple duplex and pseudoknotted RNAs.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0022-2836
pubmed:author
pubmed:copyrightInfo
Copyright 2000 Academic Press.
pubmed:issnType
Print
pubmed:day
18
pubmed:volume
296
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
659-71
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:10669615-Base Pairing, pubmed-meshheading:10669615-Base Sequence, pubmed-meshheading:10669615-Calorimetry, Differential Scanning, pubmed-meshheading:10669615-Cations, Monovalent, pubmed-meshheading:10669615-Frameshifting, Ribosomal, pubmed-meshheading:10669615-Hydrogen Bonding, pubmed-meshheading:10669615-Hydrogen-Ion Concentration, pubmed-meshheading:10669615-Luteovirus, pubmed-meshheading:10669615-Models, Molecular, pubmed-meshheading:10669615-Mutation, pubmed-meshheading:10669615-Nucleic Acid Conformation, pubmed-meshheading:10669615-Nucleic Acid Denaturation, pubmed-meshheading:10669615-RNA, Double-Stranded, pubmed-meshheading:10669615-RNA, Messenger, pubmed-meshheading:10669615-RNA, Viral, pubmed-meshheading:10669615-RNA Stability, pubmed-meshheading:10669615-Solutions, pubmed-meshheading:10669615-Thermodynamics, pubmed-meshheading:10669615-Transcription, Genetic, pubmed-meshheading:10669615-Uridine
pubmed:year
2000
pubmed:articleTitle
Energetics of a strongly pH dependent RNA tertiary structure in a frameshifting pseudoknot.
pubmed:affiliation
Department of Biochemistry, Center for Macromolecular Design, Texas A&M University, TX, 77843-2128, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't