Complex sentence: RNase E is a key regulatory enzyme in the pathway of mRNA degradation in "E. coli" that is able to auto-regulate the degradation of its own mRNA in response to changes in RNase E activity.
Split into simpler sentences: RNase E is a key regulatory enzyme in the pathway of mRNA degradation in "Escherichia coli". Its is able to auto-regulate the degradation of its own mRNA in response to changes in RNase E activity.