• Media type: E-Article
  • Title: A distinct RNA recognition mechanism governs Np 4 decapping by RppH
  • Contributor: Levenson-Palmer, Rose; Luciano, Daniel J.; Vasilyev, Nikita; Nuthanakanti, Ashok; Serganov, Alexander; Belasco, Joel G.
  • Published: Proceedings of the National Academy of Sciences, 2022
  • Published in: Proceedings of the National Academy of Sciences, 119 (2022) 6
  • Language: English
  • DOI: 10.1073/pnas.2117318119
  • ISSN: 0027-8424; 1091-6490
  • Origination:
  • Footnote:
  • Description: Significance Dinucleoside tetraphosphate alarmones function in bacteria as precursors to 5′-terminal nucleoside tetraphosphate (Np 4 ) caps, becoming incorporated at high levels into RNA during stress and thereby influencing transcript lifetimes. However, little is known about how these noncanonical caps are removed as a prelude to RNA degradation. Here, we report that the RNA pyrophosphohydrolase RppH assumes a leading role in decapping those transcripts under conditions of disulfide stress and that it recognizes Np 4 -capped 5′ ends by an unexpected mechanism, generating a triphosphorylated RNA intermediate that must undergo further deprotection by RppH to trigger degradation. These findings help to explain the uneven distribution of Np 4 caps on bacterial transcripts and have important implications for how gene expression is reprogrammed in response to stress.
  • Access State: Open Access