Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1993-2-23
pubmed:abstractText
We have applied the SELEX procedure (systematic evolution of ligands by exponential enrichment) to obtain RNA molecules that bind tightly to the Escherichia coli transcription termination factor rho. The starting pool was a population of RNA molecules 77 nucleotides (nt) long, in which was embedded a cassette of 30 nt of randomized sequence. The apparent dissociation constant of this RNA pool for hexameric rho factor was about 1 microM. After eight rounds of selection by filter binding, with RNA in either 10-fold or 40 to 100-fold excess at each step, the dissociation constant of the selected RNA had dropped by more than 500-fold to about 1 nM. Analysis of 29 clonal isolates from the population revealed that five had KDs substantially weaker than 10 nM (presumably background carryover), 40% were C-rich (as might have been predicted from rho's known substrate binding), and 40% had a strikingly preserved potential hairpin, in most cases of 6 base pairs with a 3 nt CAA loop and preceded by a CCCCA consensus. The rho-dependent trp t' terminator region includes a related potential hairpin structure; however, it is energetically unfavorable. The implications of the sequence findings for elucidating both static and dynamic aspects of rho factor recognition and response to its RNA target site are discussed.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0892-6638
pubmed:author
pubmed:issnType
Print
pubmed:volume
7
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
201-7
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Selective enrichment of RNA species for tight binding to Escherichia coli rho factor.
pubmed:affiliation
Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder 80309.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't