Linked Life Data

8943297

Source:http://linkedlifedata.com/resource/pubmed/id/8943297

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
50
pubmed:dateCreated
1997-1-17
pubmed:abstractText
Middle transcription of bacteriophage Mu requires Escherichia coli RNA polymerase and a Mu-encoded protein, Mor. Consistent with these requirements, the middle promoter, Pm, has a -10 hexamer but lacks a recognizable -35 hexamer. Interactions between Mor and RNA polymerase were studied using in vitro transcription, DNase I footprinting, and the yeast interaction trap system. We observed reduced promoter activity in vitro using reconstituted RNA polymerases with C-terminal deletions in alpha or sigma70. As predicted if alpha were binding to Pm, we detected a polymerase-dependent footprint in the -60 region. Reconstituted RNA polymerases containing Ala substitutions in the alpha C-terminal domain were used to assay Mor-dependent transcription from Pm in vitro. The D258A substitution and alpha deletion gave large reductions in activation, whereas the L262A, R265A, and N268A substitutions caused smaller reductions. The interaction trap assay revealed weak interactions between Mor and both alpha and sigma70; consistent with a key role of alpha-D258, the D258A substitution abolished interaction, whereas the R265A substitution did not. We propose that: (i) alpha-D258 is a Mor "contact site"; and (ii) residues Leu-262, Arg-265, and Asn-268 indirectly affect Mor-polymerase interaction by stabilizing the ternary complex via alpha-DNA contact.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
13
pubmed:volume
271
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
32343-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Transcription activation by the bacteriophage Mu Mor protein requires the C-terminal regions of both alpha and sigma70 subunits of Escherichia coli RNA polymerase.
pubmed:affiliation
Department of Microbiology and Immunology, University of Tennessee-Memphis, Memphis, Tennessee 38163, USA. mhowe@utmem1.utmem.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't