The ribonucleases J1 and J2 are essential for growth and have independent roles in mRNA decay in Streptococcus pyogenes
Article first published online: 16 DEC 2009
© 2009 The Authors. Journal compilation © 2009 Blackwell Publishing Ltd
Volume 75, Issue 3, pages 731–743, February 2010
How to Cite
Bugrysheva, J. V. and Scott, J. R. (2010), The ribonucleases J1 and J2 are essential for growth and have independent roles in mRNA decay in Streptococcus pyogenes. Molecular Microbiology, 75: 731–743. doi: 10.1111/j.1365-2958.2009.07012.x
- Issue published online: 24 JAN 2010
- Article first published online: 16 DEC 2009
- Accepted 3 December, 2009.
The paralogous ribonucleases J1 and J2, recently identified in Bacillus subtilis, have both endoribonucleolytic and 5′-to-3′ exoribonucleolytic activities and participate in degradation and regulatory processing of mRNA. RNases J1 and J2 have partially overlapping target specificities, but only RNase J1 is essential for B. subtilis growth. Because mRNA decay is important in regulation of virulence factors of Streptococcus pyogenes (the group A streptococcus, GAS), we investigated the role of these newly described RNases in GAS. We found that conditional mutants for both RNases J1 and J2 require induction for growth, so we conclude that, unlike the case in B. subtilis, both of these RNases are essential for GAS growth, and therefore their functions are not redundant. We compared decay of representatives of the two classes of messages we had previously identified: Class I, which decay rapidly in exponential and stationary phase of growth (hasA and gyrA), and Class II, which are stable in stationary phase and exhibit a biphasic decay curve in exponential phase (sagA and sda). We report that RNases J1 and J2 affect the rate of decay of Class I messages and the length of the first phase in decay of Class II messages.