Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1992-10-20
pubmed:abstractText
Mitochondrial run-on assays were used to determine transcriptional rates for nine B37(N) maize mitochondrial genes. Quantitation by radiographic imaging detected a 15-fold range in transcriptional rates; the order of apparent promoter strength was rps12 greater than rrn26 greater than atp6 greater than rrn18 greater than cox2 greater than atp alpha greater than atp9 greater than cox3 greater than cob. By probing single-stranded DNAs of both polarities with the run-on-products we showed that gene-specific antisense transcription did not occur. We also tested whether relative transcriptional rates were dependent on either the mitochondrial genotype or the tissue from which the mitochondria were isolated. Although tissue-specific differences in transcriptional rates were not detected, significant variation in apparent promoter strength for at least one gene, rps12, was dependent on the cytoplasmic genotype; rps12 had a five-fold reduced transcriptional rate in B37(T), the Texas male cytoplasmic strain of maize. Pulse-chase experiments suggested that differential transcript stability was not a major determinant of steady state mitochondrial RNA levels. These results indicate not only that promoter strength is an important component of the regulation of transcript levels in maize mitochondria, but also that the strength of a specific gene promoter can be dependent on the cytoplasmic genotype. Finally, the high transcriptional rate of both ribosomal RNA genes and the one mitochondrially encoded ribosomal protein gene studied suggests coordinate transcriptional regulation of both RNA and protein components of the mitochondrial ribosome.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0172-8083
pubmed:author
pubmed:issnType
Print
pubmed:volume
22
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
235-42
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Transcription in maize mitochondria: effects of tissue and mitochondrial genotype.
pubmed:affiliation
Department of Immunology and Medical Microbiology, University of Florida, Gainesville 32610.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't