C/D box sRNAs flank a split reverse gyrase gene. (a) The gene for the amino-terminal portion of the split reverse gyrase (NEQ434, black) is flanked by two box C/D sRNAs. Box C and box D elements (boxed) are indicated to highlight the permutation of the sRNA24. (b) Sequencing of inverse RT-PCR amplificates with the indicated (underlined) outward facing primers revealed circular C/D sRNAs23 and 24. The detected sites of circularization indicate that circular C/D sRNAs are slightly larger than the average length of the linear molecules amplified by RNA-Seq methodology.