New Modes of GPCR Signalling

Chemosensory and Behavior of C.elegans is Regulated by An E.Coli
Noncoding RNA
Jinjing Wu, Jing Ren, Ge Shan
Key Laboratory of Molecular Biophysics, Ministry of Education College of Life Science
and Technology, Huazhong University of Science and Technology, Wuhan 430074,
People’s Republic of China.
It has been known that food as one environmental factor can affect the expression of
genes in animal cells, although we still lack examples of this kind of effect in which the
detailed molecular mechanism is well understood. Here, we found that the expression of
a C. elegans gene, che-2, is down regulated by oxidative stressed E. coli. We
demonstrated that this down regulation is mediated by an E. coli noncoding RNA, OxyS
RNA. Oxidative stress induces the expression of OxyS in E. coli, which through a
mechanism of feeding RNA interference, suppresses the expression of che-2 in C.
elegans with a 17nt complementary sequence between OxyS and che-2 mRNA.
Agonate and Dicer, Key components in the microRNA/ RNA interference pathway in C.
elegans were shown to be required for this regulation of gene expression by E. coli
OxyS RNA. Behavior analysis indicated that oxidative stressed E. coli "utilizes" OxyS
noncoding RNA as a "repellent" to protect itself from bacterial forager such as C.
elegans. These results indicate a co-evolutionary relationship between C. elegans
and a natural food of this animal, E. coli.