RNA dynamics in aging bacterial spores.
Upon starvation, the bacterium Bacillus subtilis enters the process of sporulation, lasting several hours and culminating in formation of a spore, the most resilient cell type known. We show that a few days following sporulation, the RNA profile of spores is highly dynamic. In aging spores incubated at high temperatures, RNA content is globally decreased by degradation over several days. This degradation might be a strategy utilized by the spore to facilitate its dormancy. However, spores kept at low temperature exhibit a different RNA profile with evidence supporting transcription. Further, we demonstrate that germination is affected by spore age, incubation temperature, and RNA state, implying that spores can acquire dissimilar characteristics at a time they are considered dormant. We propose that, in contrast to current thinking, entering dormancy lasts a few days, during which spores are affected by the environment and undergo corresponding molecular changes influencing their emergence from quiescence.
Department of Microbiology and Molecular Genetics, Institute for Medical Research Israel-Canada (IMRIC), The Hebrew University-Hadassah Medical School, The Hebrew University of Jerusalem, 91120 Jerusalem, Israel.
Einat
E
Segev
Yoav
Y
Smith
Sigal
S
Ben-Yehuda
D001412:Bacillus subtilis / Q000235:genetics / Q000502:physiology*; D004722:Endoribonucleases / Q000378:metabolism; D020871:RNA Stability; D012329:RNA, Bacterial / Q000145:classification / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D012335:RNA, Ribosomal / Q000378:metabolism; D013171:Spores, Bacterial / Q000235:genetics* / Q000502:physiology; D013696:Temperature
D012329:RNA, Bacterial; D012333:RNA, Messenger; D012335:RNA, Ribosomal; D004722:Endoribonucleases