Open AccessTranscription analysis of the maize chloroplast gene for the ribosornal protein S4
Author(s) -
Debra Russell,
Lawrence Bogorad
Publication year - 1987
Publication title -
nucleic acids research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 9.008
H-Index - 537
eISSN - 1362-4954
pISSN - 0305-1048
DOI - 10.1093/nar/15.4.1853
Subject(s) - biology , gene , transcription (linguistics) , chloroplast dna , rna , promoter , nuclease , genetics , rna polymerase , start codon , coding region , rna polymerase ii , plastid , microbiology and biotechnology , chloroplast , messenger rna , gene expression , philosophy , linguistics
Maize seedlings contain several RNA species complementary to the rpS4 coding strand of the maize chloroplast ribosomal protein gene rpS4. All of these have the same 5' end about 182 bp upstream of the translation start codon for the protein S4. Northern and S1 nuclease analyses of RNA isolated from seedlings at different stages of greening show that the size of the pool of rpS4 transcripts does not change significantly upon illumination of dark-grown seedlings. The rpS4 gene has also been analyzed by in vitro transcription using maize chloroplast RNA polymerase preparations. The site of initiation in vitro has been mapped by S1 nuclease analysis to the same location as the 5' terminus of in vivo transcripts. A sequence resembling other plastid promoters occurs just upstream of this initiation site. The sensitivity of in vitro transcription to DNA template superhelicity has been assessed for the rpS4 gene promoter; its negative superhelicity-transcription rate profile resembles that of rbcL.