The gene coding for the metabolically stable 6S RNA of Escherichia coli has been 
cloned, sequenced, and partially characterized in expression analyses. The DNA 
sequence results confirm the accuracy of the previously established RNA sequence 
and, with genomic hybridization data, reveal that there is only one copy of the 
6S DNA in the chromosome. Consistent with its relaxed mode of expression, the 
promoter region of the 6S RNA gene was found to lack the hypothetical GC-rich 
discriminator domain common to other stable RNA genes under stringent control. 
The sequence results also revealed the occurrence of a 540-base-pair open 
reading frame immediately downstream from the 6S RNA coding region. Results from 
the expression analyses show that the protein and RNA coding regions are 
cotranscribed in vitro and that the open reading frame is translated in vivo.