RNase Y is an endoribonuclease that has been shown to be a key component involved in RNA metabolism in B. subtilis (1). The deletion of its gene (rny) results in the appearance of suppressor mutants under specific growth conditions. These mutants carry mutations in rpo genes encoding RNA polymerase subunits (2). This mechanism allows B. subtilis to grow even in absence of the RNase Y. However, the appearance of specific mutations in rny and their respective effect in RNA polymerase subunits genes have not been studied yet.

In order to identify the relation between the RNase Y and RNA polymerase mutants with their respective consequences in growth and adaptation, we want to identify couples of these proteins by making random mutations in rny, studying their activity and screening strains with suppressor mutations in rpo subunits of the RNA polymerase to be analyzed functionally and structurally. Considering that previous results have indicated that other components of the transcription machinery can also be affected (2), it is important to investigate their role in achieving the transcription-degradation trade-off and identify possible alterations on them.

These results will allow us to provide an approach to understand the link between transcription and RNA degradation.

(1) Commichau, F. M. et al. (2009) Novel activities of glycolytic enzymes in Bacillus subtilis: interactions with essential proteins involved in mRNA processing. Molecular & Cellular Proteomics. 8:1350-1360.

(2) Benda, M et al. (2021) Quasi-essentiality of RNase Y in Bacillus subtilis is caused by its critical role in the control of mRNA homeostasis. Nucleic Acids Research. 49:7088-7102.