Linked Life Data

9148957

Source:http://linkedlifedata.com/resource/pubmed/id/9148957

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
20
pubmed:dateCreated
1997-6-19
pubmed:abstractText
Adenine repression of the purine nucleotide biosynthetic genes in Saccharomyces cerevisiae involves down-regulation of the activator protein BAS1 or BAS2 by an unknown mechanism. To determine the minimal cis-acting requirements for adenine regulation, hybrid promoter constructs were made between ADE5,7 promoter fragments and a CYC1-lacZ reporter. A 139-nucleotide fragment containing two BAS1 binding sites was sufficient to confer adenine regulation on the CYC1-lacZ reporter. Analysis of deletion and substitution mutations led to the conclusion that the proximal BAS1 binding site is both necessary and sufficient for regulation, whereas the distal site augments the function of the proximal site. By performing saturation mutagenesis, we found two essential regions that flank the proximal site. An ABF1 consensus sequence is within one of these regions, and mutations that impaired in vitro ABF1 binding impaired promoter activity in vivo. A second region is AT-rich and appears to bind BAS2. No substitution mutations led to high level constitutive promoter activity as would be expected from removal of an upstream repression sequence. Our results indicate that ABF1, BAS1, and BAS2 are required for ADE5,7 promoter function and that adenine repression most likely involves activator modification or a negative regulator that does not itself bind DNA.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
16
pubmed:volume
272
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
13343-54
pubmed:dateRevised
2009-7-21
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
The transcriptional activators BAS1, BAS2, and ABF1 bind positive regulatory sites as the critical elements for adenine regulation of ADE5,7.
pubmed:affiliation
Department of Biology, Georgetown University, Washington, D. C. 20057, USA. rofesr@gusun.georgetown.edu
pubmed:publicationType
Journal Article