Project description:RNase J1 is the first nuclease with 5’-3’ exonuclease activity in bacteria and plays an important role in the maturation and degradation of mRNA. RNase J1 could also play a role in transcription termination of aberrant complexes. RNase J1 could bind to nascent RNA in such complexes, degrade the nascent RNA, and upon catching up with RNA polymerase (RNAP) dissociate the complex. Similar model was showed in eukaryotes. We did ChIP-seq to confirm our hypothesis.
Project description:The human protozoan parasiteEntamoeba histolyticais responsible for amebiasis, a disease endemic to developing countries.E. histolyticatrophozoites colonize the large intestine, primarily feeding on bacteria. However, in the GI, as well as in aquatic and soil microenvironments, bacterial cells form aggregates or structured communities, called biofilm, too large for phagocytosis. However, trophozoites are still able to invade and degrade bacteria under biofilm form by a mechanism mimicking digestive exophagy. E.histolytica cysteine proteinase degrade TasA, one of the main component of the biofilm matrix. Biofilm also play an important role protecting trophozoites against oxidative stress. The specific mechanism suggests that amoeba is adapted to biofilm predation and may serve as a new unexplored reservoir of novel therapeutic approaches to treat biofilms. Consistently, amoeba’s products restored antibiotic sensitivity to biofilm cells. Furthermore, our findings here show that probiotic biofilms may serve as a protective shield for mammalian cells, hindering the progression of the parasite towards them.
