FIG 4.

Electrophoretic analysis of RNA in B. subtilis spores incubated for 2 to 98 days (d). Spores were harvested from plates incubated for 2 to 98 days and were purified as described in Materials and Methods. RNA was extracted from the purified spores and analyzed either by agarose gel electrophoresis with coelectrophoresed nucleotide size markers (A) or on an Agilent TapeStation 4200 automated gel electrophoresis system (high-sensitivity RNA assay) using in silico size markers (B), as described in Materials and Methods. Bands labeled “a” and “b” in panels A and B denote the migration positions of intact 23S and 16S rRNA, respectively; note the software sizing of detected rRNA peaks in panel B is not accurate compared to the expected size of the bands detected in panel A. Samples run were from separate experiments and had RNA from two separate spore preparations harvested after 2 days. (B) The 47- and 98-day RNA lanes were from a different TapeStation run than the 2-day, 6-day, and 15-day RNA lanes.